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RIFS-ES Scheduling V1 release.
This is the Googlecode link of RIFS series. http://code.google.com/p/rifs-scheduler/ Here is the download link for RIFS.ES-v1-kernel3.4.x: http://rifs-scheduler.googlecode.com/files/RIFS.ES-v1-ker... The design of RIFS/ES: First let me list out the 3 equations of SystemV scheduling. 0.cpu = cpu +1; 1.cpu = cpu/2; 2.priority = (cpu/2) + base level priority; These 3 equations are used to determine the scheduling priority if a task. Here there is no any complex detection of interactive task(O(1) failed on desktop because of the complex detection). O(1) did a hard-coding and kerp focusing on how to detect a whether the task is an interactive task or not. CFS is good with its beautiful design. But in my opinion i think the sleeper feature will destroy the beautiful design. RIFS-ES adopt the design of System V scheduler. It can be interactive. On my box everything is very smopth Chen diff -ruN linux-3.4.1/fs/proc/base.c linux-3.4.1-RIFS/fs/proc/base.c --- linux-3.4.1/fs/proc/base.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/fs/proc/base.c 2012-06-06 15:02:18.000000000 +0800 @@ -342,7 +342,7 @@ static int proc_pid_schedstat(struct task_struct *task, char *buffer) { return sprintf(buffer, "%llu %llu %lu\n", - (unsigned long long)task->se.sum_exec_runtime, + (unsigned long long)tsk_seruntime(task), (unsigned long long)task->sched_info.run_delay, task->sched_info.pcount); } diff -ruN linux-3.4.1/include/linux/init_task.h linux-3.4.1-RIFS/include/linux/init_task.h --- linux-3.4.1/include/linux/init_task.h 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/include/linux/init_task.h 2012-06-06 14:50:29.000000000 +0800 @@ -132,12 +132,68 @@ # define INIT_PERF_EVENTS(tsk) #endif -#define INIT_TASK_COMM "swapper" - /* * INIT_TASK is used to set up the first task table, touch at * your own risk!. Base=0, limit=0x1fffff (=2MB) */ +#ifdef CONFIG_SCHED_RIFS +#define INIT_TASK_COMM "RIFS" +#define INIT_TASK(tsk) \ +{ \ + .state = 0, \ + .stack = &init_thread_info, \ + .usage = ATOMIC_INIT(2), \ + .flags = PF_KTHREAD, \ + .prio = NORMAL_PRIO, \ + .static_prio = MAX_PRIO-20, \ + .normal_prio = NORMAL_PRIO, \ + .policy = SCHED_NORMAL, \ + .cpus_allowed = CPU_MASK_ALL, \ + .mm = NULL, \ + .active_mm = &init_mm, \ + .run_list = LIST_HEAD_INIT(tsk.run_list), \ + .time_slice = HZ, \ + .tasks = LIST_HEAD_INIT(tsk.tasks), \ + INIT_PUSHABLE_TASKS(tsk) \ + .ptraced = LIST_HEAD_INIT(tsk.ptraced), \ + .ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \ + .real_parent = &tsk, \ + .parent = &tsk, \ + .children = LIST_HEAD_INIT(tsk.children), \ + .sibling = LIST_HEAD_INIT(tsk.sibling), \ + .group_leader = &tsk, \ + RCU_INIT_POINTER(.real_cred, &init_cred), \ + RCU_INIT_POINTER(.cred, &init_cred), \ + .comm = INIT_TASK_COMM, \ + .thread = INIT_THREAD, \ + .fs = &init_fs, \ + .files = &init_files, \ + .signal = &init_signals, \ + .sighand = &init_sighand, \ + .nsproxy = &init_nsproxy, \ + .pending = { \ + .list = LIST_HEAD_INIT(tsk.pending.list), \ + .signal = {{0}}}, \ + .blocked = {{0}}, \ + .alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \ + .journal_info = NULL, \ + .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ + .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ + .timer_slack_ns = 50000, /* 50 usec default slack */ \ + .pids = { \ + [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ + [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ + [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \ + }, \ + INIT_IDS \ + INIT_PERF_EVENTS(tsk) \ + INIT_TRACE_IRQFLAGS \ + INIT_LOCKDEP \ + INIT_FTRACE_GRAPH \ + INIT_TRACE_RECURSION \ + INIT_TASK_RCU_PREEMPT(tsk) \ +} +#else /* CONFIG_SCHED_RIFS */ #define INIT_TASK(tsk) \ { \ .state = 0, \ @@ -201,7 +257,7 @@ INIT_TASK_RCU_PREEMPT(tsk) \ INIT_CPUSET_SEQ \ } - +#endif #define INIT_CPU_TIMERS(cpu_timers) \ { \ diff -ruN linux-3.4.1/include/linux/init_task (复件).h linux-3.4.1-RIFS/include/linux/init_task (复件).h --- linux-3.4.1/include/linux/init_task (复件).h 1970-01-01 08:00:00.000000000 +0800 +++ linux-3.4.1-RIFS/include/linux/init_task (复件).h 2012-06-01 15:18:44.000000000 +0800 @@ -0,0 +1,217 @@ +#ifndef _LINUX__INIT_TASK_H +#define _LINUX__INIT_TASK_H + +#include <linux/rcupdate.h> +#include <linux/irqflags.h> +#include <linux/utsname.h> +#include <linux/lockdep.h> +#include <linux/ftrace.h> +#include <linux/ipc.h> +#include <linux/pid_namespace.h> +#include <linux/user_namespace.h> +#include <linux/securebits.h> +#include <net/net_namespace.h> + +#ifdef CONFIG_SMP +# define INIT_PUSHABLE_TASKS(tsk) \ + .pushable_tasks = PLIST_NODE_INIT(tsk.pushable_tasks, MAX_PRIO), +#else +# define INIT_PUSHABLE_TASKS(tsk) +#endif + +extern struct files_struct init_files; +extern struct fs_struct init_fs; + +#ifdef CONFIG_CGROUPS +#define INIT_GROUP_RWSEM(sig) \ + .group_rwsem = __RWSEM_INITIALIZER(sig.group_rwsem), +#else +#define INIT_GROUP_RWSEM(sig) +#endif + +#ifdef CONFIG_CPUSETS +#define INIT_CPUSET_SEQ \ + .mems_allowed_seq = SEQCNT_ZERO, +#else +#define INIT_CPUSET_SEQ +#endif + +#define INIT_SIGNALS(sig) { \ + .nr_threads = 1, \ + .wait_chldexit = __WAIT_QUEUE_HEAD_INITIALIZER(sig.wait_chldexit),\ + .shared_pending = { \ + .list = LIST_HEAD_INIT(sig.shared_pending.list), \ + .signal = {{0}}}, \ + .posix_timers = LIST_HEAD_INIT(sig.posix_timers), \ + .cpu_timers = INIT_CPU_TIMERS(sig.cpu_timers), \ + .rlim = INIT_RLIMITS, \ + .cputimer = { \ + .cputime = INIT_CPUTIME, \ + .running = 0, \ + .lock = __RAW_SPIN_LOCK_UNLOCKED(sig.cputimer.lock), \ + }, \ + .cred_guard_mutex = \ + __MUTEX_INITIALIZER(sig.cred_guard_mutex), \ + INIT_GROUP_RWSEM(sig) \ +} + +extern struct nsproxy init_nsproxy; + +#define INIT_SIGHAND(sighand) { \ + .count = ATOMIC_INIT(1), \ + .action = { { { .sa_handler = SIG_DFL, } }, }, \ + .siglock = __SPIN_LOCK_UNLOCKED(sighand.siglock), \ + .signalfd_wqh = __WAIT_QUEUE_HEAD_INITIALIZER(sighand.signalfd_wqh), \ +} + +extern struct group_info init_groups; + +#define INIT_STRUCT_PID { \ + .count = ATOMIC_INIT(1), \ + .tasks = { \ + { .first = NULL }, \ + { .first = NULL }, \ + { .first = NULL }, \ + }, \ + .level = 0, \ + .numbers = { { \ + .nr = 0, \ + .ns = &init_pid_ns, \ + .pid_chain = { .next = NULL, .pprev = NULL }, \ + }, } \ +} + +#define INIT_PID_LINK(type) \ +{ \ + .node = { \ + .next = NULL, \ + .pprev = NULL, \ + }, \ + .pid = &init_struct_pid, \ +} + +#ifdef CONFIG_AUDITSYSCALL +#define INIT_IDS \ + .loginuid = -1, \ + .sessionid = -1, +#else +#define INIT_IDS +#endif + +#ifdef CONFIG_RCU_BOOST +#define INIT_TASK_RCU_BOOST() \ + .rcu_boost_mutex = NULL, +#else +#define INIT_TASK_RCU_BOOST() +#endif +#ifdef CONFIG_TREE_PREEMPT_RCU +#define INIT_TASK_RCU_TREE_PREEMPT() \ + .rcu_blocked_node = NULL, +#else +#define INIT_TASK_RCU_TREE_PREEMPT(tsk) +#endif +#ifdef CONFIG_PREEMPT_RCU +#define INIT_TASK_RCU_PREEMPT(tsk) \ + .rcu_read_lock_nesting = 0, \ + .rcu_read_unlock_special = 0, \ + .rcu_node_entry = LIST_HEAD_INIT(tsk.rcu_node_entry), \ + INIT_TASK_RCU_TREE_PREEMPT() \ + INIT_TASK_RCU_BOOST() +#else +#define INIT_TASK_RCU_PREEMPT(tsk) +#endif + +extern struct cred init_cred; + +#ifdef CONFIG_PERF_EVENTS +# define INIT_PERF_EVENTS(tsk) \ + .perf_event_mutex = \ + __MUTEX_INITIALIZER(tsk.perf_event_mutex), \ + .perf_event_list = LIST_HEAD_INIT(tsk.perf_event_list), +#else +# define INIT_PERF_EVENTS(tsk) +#endif + +#define INIT_TASK_COMM "swapper" + +/* + * INIT_TASK is used to set up the first task table, touch at + * your own risk!. Base=0, limit=0x1fffff (=2MB) + */ +#define INIT_TASK(tsk) \ +{ \ + .state = 0, \ + .stack = &init_thread_info, \ + .usage = ATOMIC_INIT(2), \ + .flags = PF_KTHREAD, \ + .prio = MAX_PRIO-20, \ + .static_prio = MAX_PRIO-20, \ + .normal_prio = MAX_PRIO-20, \ + .policy = SCHED_NORMAL, \ + .cpus_allowed = CPU_MASK_ALL, \ + .mm = NULL, \ + .active_mm = &init_mm, \ + .se = { \ + .group_node = LIST_HEAD_INIT(tsk.se.group_node), \ + }, \ + .rt = { \ + .run_list = LIST_HEAD_INIT(tsk.rt.run_list), \ + .time_slice = RR_TIMESLICE, \ + .nr_cpus_allowed = NR_CPUS, \ + }, \ + .tasks = LIST_HEAD_INIT(tsk.tasks), \ + INIT_PUSHABLE_TASKS(tsk) \ + .ptraced = LIST_HEAD_INIT(tsk.ptraced), \ + .ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \ + .real_parent = &tsk, \ + .parent = &tsk, \ + .children = LIST_HEAD_INIT(tsk.children), \ + .sibling = LIST_HEAD_INIT(tsk.sibling), \ + .group_leader = &tsk, \ + RCU_INIT_POINTER(.real_cred, &init_cred), \ + RCU_INIT_POINTER(.cred, &init_cred), \ + .comm = INIT_TASK_COMM, \ + .thread = INIT_THREAD, \ + .fs = &init_fs, \ + .files = &init_files, \ + .signal = &init_signals, \ + .sighand = &init_sighand, \ + .nsproxy = &init_nsproxy, \ + .pending = { \ + .list = LIST_HEAD_INIT(tsk.pending.list), \ + .signal = {{0}}}, \ + .blocked = {{0}}, \ + .alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \ + .journal_info = NULL, \ + .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ + .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ + .timer_slack_ns = 50000, /* 50 usec default slack */ \ + .pids = { \ + [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ + [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ + [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \ + }, \ + .thread_group = LIST_HEAD_INIT(tsk.thread_group), \ + INIT_IDS \ + INIT_PERF_EVENTS(tsk) \ + INIT_TRACE_IRQFLAGS \ + INIT_LOCKDEP \ + INIT_FTRACE_GRAPH \ + INIT_TRACE_RECURSION \ + INIT_TASK_RCU_PREEMPT(tsk) \ + INIT_CPUSET_SEQ \ +} + + +#define INIT_CPU_TIMERS(cpu_timers) \ +{ \ + LIST_HEAD_INIT(cpu_timers[0]), \ + LIST_HEAD_INIT(cpu_timers[1]), \ + LIST_HEAD_INIT(cpu_timers[2]), \ +} + +/* Attach to the init_task data structure for proper alignment */ +#define __init_task_data __attribute__((__section__(".data..init_task"))) + + +#endif diff -ruN linux-3.4.1/include/linux/sched.h linux-3.4.1-RIFS/include/linux/sched.h --- linux-3.4.1/include/linux/sched.h 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/include/linux/sched.h 2012-06-06 14:57:06.000000000 +0800 @@ -37,9 +37,13 @@ #define SCHED_FIFO 1 #define SCHED_RR 2 #define SCHED_BATCH 3 -/* SCHED_ISO: reserved but not implemented yet */ #define SCHED_IDLE 5 -/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ +#define SCHED_IDLEPRIO SCHED_IDLE +#ifdef CONFIG_SCHED_RIFS +#define SCHED_MAX (SCHED_IDLEPRIO) +#define SCHED_RANGE(policy) ((policy) <= SCHED_MAX) +#endif + #define SCHED_RESET_ON_FORK 0x40000000 #ifdef __KERNEL__ @@ -268,8 +272,6 @@ extern void init_idle(struct task_struct *idle, int cpu); extern void init_idle_bootup_task(struct task_struct *idle); -extern int runqueue_is_locked(int cpu); - #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) extern void select_nohz_load_balancer(int stop_tick); extern void set_cpu_sd_state_idle(void); @@ -1270,15 +1272,33 @@ #ifdef CONFIG_SMP struct llist_node wake_entry; - int on_cpu; #endif +#ifndef CONFIG_SCHED_RIFS + int on_cpu; int on_rq; - +#else + bool on_cpu; + bool on_rq; +#endif int prio, static_prio, normal_prio; unsigned int rt_priority; +#ifdef CONFIG_SCHED_RIFS + int time_slice; + u64 crt_time; + u64 run_time; + u64 run_scale; + struct list_head run_list; + u64 last_ran; + u64 sched_time; /* sched_clock time spent running */ +#ifdef CONFIG_SMP + bool sticky; /* Soft affined flag */ +#endif + unsigned long rt_timeout; +#else /* CONFIG_SCHED_RIFS */ const struct sched_class *sched_class; struct sched_entity se; struct sched_rt_entity rt; +#endif #ifdef CONFIG_PREEMPT_NOTIFIERS /* list of struct preempt_notifier: */ @@ -1391,6 +1411,9 @@ cputime_t utime, stime, utimescaled, stimescaled; cputime_t gtime; +#ifdef CONFIG_SCHED_RIFS + unsigned long utime_pc, stime_pc; +#endif #ifndef CONFIG_VIRT_CPU_ACCOUNTING cputime_t prev_utime, prev_stime; #endif @@ -1619,6 +1642,55 @@ #endif }; +#ifdef CONFIG_SCHED_RIFS +bool grunqueue_is_locked(void); +void grq_unlock_wait(void); +void cpu_scaling(int cpu); +void cpu_nonscaling(int cpu); +bool above_background_load(void); +#define tsk_seruntime(t) ((t)->sched_time) +#define tsk_rttimeout(t) ((t)->rt_timeout) + +static inline void tsk_cpus_current(struct task_struct *p) +{ +} + +static inline int runqueue_is_locked(int cpu) +{ + return grunqueue_is_locked(); +} + +void print_scheduler_version(void); + +#else /* CFS */ +extern int runqueue_is_locked(int cpu); +static inline void cpu_scaling(int cpu) +{ +} + +static inline void cpu_nonscaling(int cpu) +{ +} +#define tsk_seruntime(t) ((t)->se.sum_exec_runtime) +#define tsk_rttimeout(t) ((t)->rt.timeout) + +static inline void tsk_cpus_current(struct task_struct *p) +{ + p->rt.nr_cpus_allowed = current->rt.nr_cpus_allowed; +} + +static inline void print_scheduler_version(void) +{ + printk(KERN_INFO"CFS CPU scheduler.\n"); +} + +/* Anyone feel like implementing this? */ +static inline bool above_background_load(void) +{ + return false; +} +#endif /* CONFIG_SCHED_RIFS */ + /* Future-safe accessor for struct task_struct's cpus_allowed. */ #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) @@ -1636,10 +1708,20 @@ */ #define MAX_USER_RT_PRIO 100 -#define MAX_RT_PRIO MAX_USER_RT_PRIO +#define MAX_RT_PRIO (MAX_USER_RT_PRIO) +#define DEFAULT_PRIO (MAX_RT_PRIO + 20) +#ifdef CONFIG_SCHED_RIFS +#define PRIO_RANGE (40) +#define MAX_PRIO (MAX_RT_PRIO + PRIO_RANGE) +//#define ISO_PRIO (MAX_RT_PRIO) 已经被我干掉，哈哈 +#define NORMAL_PRIO (MAX_RT_PRIO + 1) +#define IDLE_PRIO (MAX_PRIO + 1) +#define PRIO_LIMIT ((IDLE_PRIO) + 1) +#else /* CONFIG_SCHED_RIFS */ #define MAX_PRIO (MAX_RT_PRIO + 40) -#define DEFAULT_PRIO (MAX_RT_PRIO + 20) +#define NORMAL_PRIO (DEFAULT_PRIO) +#endif /* CONFIG_SCHED_RIFS */ static inline int rt_prio(int prio) { @@ -2002,7 +2084,7 @@ task_sched_runtime(struct task_struct *task); /* sched_exec is called by processes performing an exec */ -#ifdef CONFIG_SMP +#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_RIFS) extern void sched_exec(void); #else #define sched_exec() {} diff -ruN linux-3.4.1/include/linux/sched (复件).h linux-3.4.1-RIFS/include/linux/sched (复件).h --- linux-3.4.1/include/linux/sched (复件).h 1970-01-01 08:00:00.000000000 +0800 +++ linux-3.4.1-RIFS/include/linux/sched (复件).h 2012-06-01 15:18:44.000000000 +0800 @@ -0,0 +1,2823 @@ +#ifndef _LINUX_SCHED_H +#define _LINUX_SCHED_H + +/* + * cloning flags: + */ +#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ +#define CLONE_VM 0x00000100 /* set if VM shared between processes */ +#define CLONE_FS 0x00000200 /* set if fs info shared between processes */ +#define CLONE_FILES 0x00000400 /* set if open files shared between processes */ +#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */ +#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */ +#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */ +#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */ +#define CLONE_THREAD 0x00010000 /* Same thread group? */ +#define CLONE_NEWNS 0x00020000 /* New namespace group? */ +#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */ +#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */ +#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */ +#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */ +#define CLONE_DETACHED 0x00400000 /* Unused, ignored */ +#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */ +#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ +/* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state) + and is now available for re-use. */ +#define CLONE_NEWUTS 0x04000000 /* New utsname group? */ +#define CLONE_NEWIPC 0x08000000 /* New ipcs */ +#define CLONE_NEWUSER 0x10000000 /* New user namespace */ +#define CLONE_NEWPID 0x20000000 /* New pid namespace */ +#define CLONE_NEWNET 0x40000000 /* New network namespace */ +#define CLONE_IO 0x80000000 /* Clone io context */ + +/* + * Scheduling policies + */ +#define SCHED_NORMAL 0 +#define SCHED_FIFO 1 +#define SCHED_RR 2 +#define SCHED_BATCH 3 +/* SCHED_ISO: reserved but not implemented yet */ +#define SCHED_IDLE 5 +/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ +#define SCHED_RESET_ON_FORK 0x40000000 + +#ifdef __KERNEL__ + +struct sched_param { + int sched_priority; +}; + +#include <asm/param.h> /* for HZ */ + +#include <linux/capability.h> +#include <linux/threads.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/timex.h> +#include <linux/jiffies.h> +#include <linux/rbtree.h> +#include <linux/thread_info.h> +#include <linux/cpumask.h> +#include <linux/errno.h> +#include <linux/nodemask.h> +#include <linux/mm_types.h> + +#include <asm/page.h> +#include <asm/ptrace.h> +#include <asm/cputime.h> + +#include <linux/smp.h> +#include <linux/sem.h> +#include <linux/signal.h> +#include <linux/compiler.h> +#include <linux/completion.h> +#include <linux/pid.h> +#include <linux/percpu.h> +#include <linux/topology.h> +#include <linux/proportions.h> +#include <linux/seccomp.h> +#include <linux/rcupdate.h> +#include <linux/rculist.h> +#include <linux/rtmutex.h> + +#include <linux/time.h> +#include <linux/param.h> +#include <linux/resource.h> +#include <linux/timer.h> +#include <linux/hrtimer.h> +#include <linux/task_io_accounting.h> +#include <linux/latencytop.h> +#include <linux/cred.h> +#include <linux/llist.h> + +#include <asm/processor.h> + +struct exec_domain; +struct futex_pi_state; +struct robust_list_head; +struct bio_list; +struct fs_struct; +struct perf_event_context; +struct blk_plug; + +/* + * List of flags we want to share for kernel threads, + * if only because they are not used by them anyway. + */ +#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) + +/* + * These are the constant used to fake the fixed-point load-average + * counting. Some notes: + * - 11 bit fractions expand to 22 bits by the multiplies: this gives + * a load-average precision of 10 bits integer + 11 bits fractional + * - if you want to count load-averages more often, you need more + * precision, or rounding will get you. With 2-second counting freq, + * the EXP_n values would be 1981, 2034 and 2043 if still using only + * 11 bit fractions. + */ +extern unsigned long avenrun[]; /* Load averages */ +extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); + +#define FSHIFT 11 /* nr of bits of precision */ +#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ +#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ +#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ +#define EXP_5 2014 /* 1/exp(5sec/5min) */ +#define EXP_15 2037 /* 1/exp(5sec/15min) */ + +#define CALC_LOAD(load,exp,n) \ + load *= exp; \ + load += n*(FIXED_1-exp); \ + load >>= FSHIFT; + +extern unsigned long total_forks; +extern int nr_threads; +DECLARE_PER_CPU(unsigned long, process_counts); +extern int nr_processes(void); +extern unsigned long nr_running(void); +extern unsigned long nr_uninterruptible(void); +extern unsigned long nr_iowait(void); +extern unsigned long nr_iowait_cpu(int cpu); +extern unsigned long this_cpu_load(void); + + +extern void calc_global_load(unsigned long ticks); + +extern unsigned long get_parent_ip(unsigned long addr); + +struct seq_file; +struct cfs_rq; +struct task_group; +#ifdef CONFIG_SCHED_DEBUG +extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); +extern void proc_sched_set_task(struct task_struct *p); +extern void +print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); +#else +static inline void +proc_sched_show_task(struct task_struct *p, struct seq_file *m) +{ +} +static inline void proc_sched_set_task(struct task_struct *p) +{ +} +static inline void +print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) +{ +} +#endif + +/* + * Task state bitmask. NOTE! These bits are also + * encoded in fs/proc/array.c: get_task_state(). + * + * We have two separate sets of flags: task->state + * is about runnability, while task->exit_state are + * about the task exiting. Confusing, but this way + * modifying one set can't modify the other one by + * mistake. + */ +#define TASK_RUNNING 0 +#define TASK_INTERRUPTIBLE 1 +#define TASK_UNINTERRUPTIBLE 2 +#define __TASK_STOPPED 4 +#define __TASK_TRACED 8 +/* in tsk->exit_state */ +#define EXIT_ZOMBIE 16 +#define EXIT_DEAD 32 +/* in tsk->state again */ +#define TASK_DEAD 64 +#define TASK_WAKEKILL 128 +#define TASK_WAKING 256 +#define TASK_STATE_MAX 512 + +#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW" + +extern char ___assert_task_state[1 - 2*!!( + sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; + +/* Convenience macros for the sake of set_task_state */ +#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) +#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) +#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) + +/* Convenience macros for the sake of wake_up */ +#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) +#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) + +/* get_task_state() */ +#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ + TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ + __TASK_TRACED) + +#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) +#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) +#define task_is_dead(task) ((task)->exit_state != 0) +#define task_is_stopped_or_traced(task) \ + ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) +#define task_contributes_to_load(task) \ + ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ + (task->flags & PF_FROZEN) == 0) + +#define __set_task_state(tsk, state_value) \ + do { (tsk)->state = (state_value); } while (0) +#define set_task_state(tsk, state_value) \ + set_mb((tsk)->state, (state_value)) + +/* + * set_current_state() includes a barrier so that the write of current->state + * is correctly serialised wrt the caller's subsequent test of whether to + * actually sleep: + * + * set_current_state(TASK_UNINTERRUPTIBLE); + * if (do_i_need_to_sleep()) + * schedule(); + * + * If the caller does not need such serialisation then use __set_current_state() + */ +#define __set_current_state(state_value) \ + do { current->state = (state_value); } while (0) +#define set_current_state(state_value) \ + set_mb(current->state, (state_value)) + +/* Task command name length */ +#define TASK_COMM_LEN 16 + +#include <linux/spinlock.h> + +/* + * This serializes "schedule()" and also protects + * the run-queue from deletions/modifications (but + * _adding_ to the beginning of the run-queue has + * a separate lock). + */ +extern rwlock_t tasklist_lock; +extern spinlock_t mmlist_lock; + +struct task_struct; + +#ifdef CONFIG_PROVE_RCU +extern int lockdep_tasklist_lock_is_held(void); +#endif /* #ifdef CONFIG_PROVE_RCU */ + +extern void sched_init(void); +extern void sched_init_smp(void); +extern asmlinkage void schedule_tail(struct task_struct *prev); +extern void init_idle(struct task_struct *idle, int cpu); +extern void init_idle_bootup_task(struct task_struct *idle); + +extern int runqueue_is_locked(int cpu); + +#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) +extern void select_nohz_load_balancer(int stop_tick); +extern void set_cpu_sd_state_idle(void); +extern int get_nohz_timer_target(void); +#else +static inline void select_nohz_load_balancer(int stop_tick) { } +static inline void set_cpu_sd_state_idle(void) { } +#endif + +/* + * Only dump TASK_* tasks. (0 for all tasks) + */ +extern void show_state_filter(unsigned long state_filter); + +static inline void show_state(void) +{ + show_state_filter(0); +} + +extern void show_regs(struct pt_regs *); + +/* + * TASK is a pointer to the task whose backtrace we want to see (or NULL for current + * task), SP is the stack pointer of the first frame that should be shown in the back + * trace (or NULL if the entire call-chain of the task should be shown). + */ +extern void show_stack(struct task_struct *task, unsigned long *sp); + +void io_schedule(void); +long io_schedule_timeout(long timeout); + +extern void cpu_init (void); +extern void trap_init(void); +extern void update_process_times(int user); +extern void scheduler_tick(void); + +extern void sched_show_task(struct task_struct *p); + +#ifdef CONFIG_LOCKUP_DETECTOR +extern void touch_softlockup_watchdog(void); +extern void touch_softlockup_watchdog_sync(void); +extern void touch_all_softlockup_watchdogs(void); +extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, + void __user *buffer, + size_t *lenp, loff_t *ppos); +extern unsigned int softlockup_panic; +void lockup_detector_init(void); +#else +static inline void touch_softlockup_watchdog(void) +{ +} +static inline void touch_softlockup_watchdog_sync(void) +{ +} +static inline void touch_all_softlockup_watchdogs(void) +{ +} +static inline void lockup_detector_init(void) +{ +} +#endif + +#ifdef CONFIG_DETECT_HUNG_TASK +extern unsigned int sysctl_hung_task_panic; +extern unsigned long sysctl_hung_task_check_count; +extern unsigned long sysctl_hung_task_timeout_secs; +extern unsigned long sysctl_hung_task_warnings; +extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, + void __user *buffer, + size_t *lenp, loff_t *ppos); +#else +/* Avoid need for ifdefs elsewhere in the code */ +enum { sysctl_hung_task_timeout_secs = 0 }; +#endif + +/* Attach to any functions which should be ignored in wchan output. */ +#define __sched __attribute__((__section__(".sched.text"))) + +/* Linker adds these: start and end of __sched functions */ +extern char __sched_text_start[], __sched_text_end[]; + +/* Is this address in the __sched functions? */ +extern int in_sched_functions(unsigned long addr); + +#define MAX_SCHEDULE_TIMEOUT LONG_MAX +extern signed long schedule_timeout(signed long timeout); +extern signed long schedule_timeout_interruptible(signed long timeout); +extern signed long schedule_timeout_killable(signed long timeout); +extern signed long schedule_timeout_uninterruptible(signed long timeout); +asmlinkage void schedule(void); +extern void schedule_preempt_disabled(void); +extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner); + +struct nsproxy; +struct user_namespace; + +/* + * Default maximum number of active map areas, this limits the number of vmas + * per mm struct. Users can overwrite this number by sysctl but there is a + * problem. + * + * When a program's coredump is generated as ELF format, a section is created + * per a vma. In ELF, the number of sections is represented in unsigned short. + * This means the number of sections should be smaller than 65535 at coredump. + * Because the kernel adds some informative sections to a image of program at + * generating coredump, we need some margin. The number of extra sections is + * 1-3 now and depends on arch. We use "5" as safe margin, here. + */ +#define MAPCOUNT_ELF_CORE_MARGIN (5) +#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) + +extern int sysctl_max_map_count; + +#include <linux/aio.h> + +#ifdef CONFIG_MMU +extern void arch_pick_mmap_layout(struct mm_struct *mm); +extern unsigned long +arch_get_unmapped_area(struct file *, unsigned long, unsigned long, + unsigned long, unsigned long); +extern unsigned long +arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags); +extern void arch_unmap_area(struct mm_struct *, unsigned long); +extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); +#else +static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} +#endif + + +extern void set_dumpable(struct mm_struct *mm, int value); +extern int get_dumpable(struct mm_struct *mm); + +/* mm flags */ +/* dumpable bits */ +#define MMF_DUMPABLE 0 /* core dump is permitted */ +#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ + +#define MMF_DUMPABLE_BITS 2 +#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) + +/* coredump filter bits */ +#define MMF_DUMP_ANON_PRIVATE 2 +#define MMF_DUMP_ANON_SHARED 3 +#define MMF_DUMP_MAPPED_PRIVATE 4 +#define MMF_DUMP_MAPPED_SHARED 5 +#define MMF_DUMP_ELF_HEADERS 6 +#define MMF_DUMP_HUGETLB_PRIVATE 7 +#define MMF_DUMP_HUGETLB_SHARED 8 + +#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS +#define MMF_DUMP_FILTER_BITS 7 +#define MMF_DUMP_FILTER_MASK \ + (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) +#define MMF_DUMP_FILTER_DEFAULT \ + ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ + (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) + +#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS +# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) +#else +# define MMF_DUMP_MASK_DEFAULT_ELF 0 +#endif + /* leave room for more dump flags */ +#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ +#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ + +#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) + +struct sighand_struct { + atomic_t count; + struct k_sigaction action[_NSIG]; + spinlock_t siglock; + wait_queue_head_t signalfd_wqh; +}; + +struct pacct_struct { + int ac_flag; + long ac_exitcode; + unsigned long ac_mem; + cputime_t ac_utime, ac_stime; + unsigned long ac_minflt, ac_majflt; +}; + +struct cpu_itimer { + cputime_t expires; + cputime_t incr; + u32 error; + u32 incr_error; +}; + +/** + * struct task_cputime - collected CPU time counts + * @utime: time spent in user mode, in &cputime_t units + * @stime: time spent in kernel mode, in &cputime_t units + * @sum_exec_runtime: total time spent on the CPU, in nanoseconds + * + * This structure groups together three kinds of CPU time that are + * tracked for threads and thread groups. Most things considering + * CPU time want to group these counts together and treat all three + * of them in parallel. + */ +struct task_cputime { + cputime_t utime; + cputime_t stime; + unsigned long long sum_exec_runtime; +}; +/* Alternate field names when used to cache expirations. */ +#define prof_exp stime +#define virt_exp utime +#define sched_exp sum_exec_runtime + +#define INIT_CPUTIME \ + (struct task_cputime) { \ + .utime = 0, \ + .stime = 0, \ + .sum_exec_runtime = 0, \ + } + +/* + * Disable preemption until the scheduler is running. + * Reset by start_kernel()->sched_init()->init_idle(). + * + * We include PREEMPT_ACTIVE to avoid cond_resched() from working + * before the scheduler is active -- see should_resched(). + */ +#define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE) + +/** + * struct thread_group_cputimer - thread group interval timer counts + * @cputime: thread group interval timers. + * @running: non-zero when there are timers running and + * @cputime receives updates. + * @lock: lock for fields in this struct. + * + * This structure contains the version of task_cputime, above, that is + * used for thread group CPU timer calculations. + */ +struct thread_group_cputimer { + struct task_cputime cputime; + int running; + raw_spinlock_t lock; +}; + +#include <linux/rwsem.h> +struct autogroup; + +/* + * NOTE! "signal_struct" does not have its own + * locking, because a shared signal_struct always + * implies a shared sighand_struct, so locking + * sighand_struct is always a proper superset of + * the locking of signal_struct. + */ +struct signal_struct { + atomic_t sigcnt; + atomic_t live; + int nr_threads; + + wait_queue_head_t wait_chldexit; /* for wait4() */ + + /* current thread group signal load-balancing target: */ + struct task_struct *curr_target; + + /* shared signal handling: */ + struct sigpending shared_pending; + + /* thread group exit support */ + int group_exit_code; + /* overloaded: + * - notify group_exit_task when ->count is equal to notify_count + * - everyone except group_exit_task is stopped during signal delivery + * of fatal signals, group_exit_task processes the signal. + */ + int notify_count; + struct task_struct *group_exit_task; + + /* thread group stop support, overloads group_exit_code too */ + int group_stop_count; + unsigned int flags; /* see SIGNAL_* flags below */ + + /* + * PR_SET_CHILD_SUBREAPER marks a process, like a service + * manager, to re-parent orphan (double-forking) child processes + * to this process instead of 'init'. The service manager is + * able to receive SIGCHLD signals and is able to investigate + * the process until it calls wait(). All children of this + * process will inherit a flag if they should look for a + * child_subreaper process at exit. + */ + unsigned int is_child_subreaper:1; + unsigned int has_child_subreaper:1; + + /* POSIX.1b Interval Timers */ + struct list_head posix_timers; + + /* ITIMER_REAL timer for the process */ + struct hrtimer real_timer; + struct pid *leader_pid; + ktime_t it_real_incr; + + /* + * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use + * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these + * values are defined to 0 and 1 respectively + */ + struct cpu_itimer it[2]; + + /* + * Thread group totals for process CPU timers. + * See thread_group_cputimer(), et al, for details. + */ + struct thread_group_cputimer cputimer; + + /* Earliest-expiration cache. */ + struct task_cputime cputime_expires; + + struct list_head cpu_timers[3]; + + struct pid *tty_old_pgrp; + + /* boolean value for session group leader */ + int leader; + + struct tty_struct *tty; /* NULL if no tty */ + +#ifdef CONFIG_SCHED_AUTOGROUP + struct autogroup *autogroup; +#endif + /* + * Cumulative resource counters for dead threads in the group, + * and for reaped dead child processes forked by this group. + * Live threads maintain their own counters and add to these + * in __exit_signal, except for the group leader. + */ + cputime_t utime, stime, cutime, cstime; + cputime_t gtime; + cputime_t cgtime; +#ifndef CONFIG_VIRT_CPU_ACCOUNTING + cputime_t prev_utime, prev_stime; +#endif + unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; + unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; + unsigned long inblock, oublock, cinblock, coublock; + unsigned long maxrss, cmaxrss; + struct task_io_accounting ioac; + + /* + * Cumulative ns of schedule CPU time fo dead threads in the + * group, not including a zombie group leader, (This only differs + * from jiffies_to_ns(utime + stime) if sched_clock uses something + * other than jiffies.) + */ + unsigned long long sum_sched_runtime; + + /* + * We don't bother to synchronize most readers of this at all, + * because there is no reader checking a limit that actually needs + * to get both rlim_cur and rlim_max atomically, and either one + * alone is a single word that can safely be read normally. + * getrlimit/setrlimit use task_lock(current->group_leader) to + * protect this instead of the siglock, because they really + * have no need to disable irqs. + */ + struct rlimit rlim[RLIM_NLIMITS]; + +#ifdef CONFIG_BSD_PROCESS_ACCT + struct pacct_struct pacct; /* per-process accounting information */ +#endif +#ifdef CONFIG_TASKSTATS + struct taskstats *stats; +#endif +#ifdef CONFIG_AUDIT + unsigned audit_tty; + struct tty_audit_buf *tty_audit_buf; +#endif +#ifdef CONFIG_CGROUPS + /* + * group_rwsem prevents new tasks from entering the threadgroup and + * member tasks from exiting,a more specifically, setting of + * PF_EXITING. fork and exit paths are protected with this rwsem + * using threadgroup_change_begin/end(). Users which require + * threadgroup to remain stable should use threadgroup_[un]lock() + * which also takes care of exec path. Currently, cgroup is the + * only user. + */ + struct rw_semaphore group_rwsem; +#endif + + int oom_adj; /* OOM kill score adjustment (bit shift) */ + int oom_score_adj; /* OOM kill score adjustment */ + int oom_score_adj_min; /* OOM kill score adjustment minimum value. + * Only settable by CAP_SYS_RESOURCE. */ + + struct mutex cred_guard_mutex; /* guard against foreign influences on + * credential calculations + * (notably. ptrace) */ +}; + +/* Context switch must be unlocked if interrupts are to be enabled */ +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW +# define __ARCH_WANT_UNLOCKED_CTXSW +#endif + +/* + * Bits in flags field of signal_struct. + */ +#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ +#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ +#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ +/* + * Pending notifications to parent. + */ +#define SIGNAL_CLD_STOPPED 0x00000010 +#define SIGNAL_CLD_CONTINUED 0x00000020 +#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) + +#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ + +/* If true, all threads except ->group_exit_task have pending SIGKILL */ +static inline int signal_group_exit(const struct signal_struct *sig) +{ + return (sig->flags & SIGNAL_GROUP_EXIT) || + (sig->group_exit_task != NULL); +} + +/* + * Some day this will be a full-fledged user tracking system.. + */ +struct user_struct { + atomic_t __count; /* reference count */ + atomic_t processes; /* How many processes does this user have? */ + atomic_t files; /* How many open files does this user have? */ + atomic_t sigpending; /* How many pending signals does this user have? */ +#ifdef CONFIG_INOTIFY_USER + atomic_t inotify_watches; /* How many inotify watches does this user have? */ + atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ +#endif +#ifdef CONFIG_FANOTIFY + atomic_t fanotify_listeners; +#endif +#ifdef CONFIG_EPOLL + atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ +#endif +#ifdef CONFIG_POSIX_MQUEUE + /* protected by mq_lock */ + unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ +#endif + unsigned long locked_shm; /* How many pages of mlocked shm ? */ + +#ifdef CONFIG_KEYS + struct key *uid_keyring; /* UID specific keyring */ + struct key *session_keyring; /* UID's default session keyring */ +#endif + + /* Hash table maintenance information */ + struct hlist_node uidhash_node; + uid_t uid; + struct user_namespace *user_ns; + +#ifdef CONFIG_PERF_EVENTS + atomic_long_t locked_vm; +#endif +}; + +extern int uids_sysfs_init(void); + +extern struct user_struct *find_user(uid_t); + +extern struct user_struct root_user; +#define INIT_USER (&root_user) + + +struct backing_dev_info; +struct reclaim_state; + +#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) +struct sched_info { + /* cumulative counters */ + unsigned long pcount; /* # of times run on this cpu */ + unsigned long long run_delay; /* time spent waiting on a runqueue */ + + /* timestamps */ + unsigned long long last_arrival,/* when we last ran on a cpu */ + last_queued; /* when we were last queued to run */ +}; +#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ + +#ifdef CONFIG_TASK_DELAY_ACCT +struct task_delay_info { + spinlock_t lock; + unsigned int flags; /* Private per-task flags */ + + /* For each stat XXX, add following, aligned appropriately + * + * struct timespec XXX_start, XXX_end; + * u64 XXX_delay; + * u32 XXX_count; + * + * Atomicity of updates to XXX_delay, XXX_count protected by + * single lock above (split into XXX_lock if contention is an issue). + */ + + /* + * XXX_count is incremented on every XXX operation, the delay + * associated with the operation is added to XXX_delay. + * XXX_delay contains the accumulated delay time in nanoseconds. + */ + struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ + u64 blkio_delay; /* wait for sync block io completion */ + u64 swapin_delay; /* wait for swapin block io completion */ + u32 blkio_count; /* total count of the number of sync block */ + /* io operations performed */ + u32 swapin_count; /* total count of the number of swapin block */ + /* io operations performed */ + + struct timespec freepages_start, freepages_end; + u64 freepages_delay; /* wait for memory reclaim */ + u32 freepages_count; /* total count of memory reclaim */ +}; +#endif /* CONFIG_TASK_DELAY_ACCT */ + +static inline int sched_info_on(void) +{ +#ifdef CONFIG_SCHEDSTATS + return 1; +#elif defined(CONFIG_TASK_DELAY_ACCT) + extern int delayacct_on; + return delayacct_on; +#else + return 0; +#endif +} + +enum cpu_idle_type { + CPU_IDLE, + CPU_NOT_IDLE, + CPU_NEWLY_IDLE, + CPU_MAX_IDLE_TYPES +}; + +/* + * Increase resolution of nice-level calculations for 64-bit architectures. + * The extra resolution improves shares distribution and load balancing of + * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup + * hierarchies, especially on larger systems. This is not a user-visible change + * and does not change the user-interface for setting shares/weights. + * + * We increase resolution only if we have enough bits to allow this increased + * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution + * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the + * increased costs. + */ +#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */ +# define SCHED_LOAD_RESOLUTION 10 +# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION) +# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION) +#else +# define SCHED_LOAD_RESOLUTION 0 +# define scale_load(w) (w) +# define scale_load_down(w) (w) +#endif + +#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION) +#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) + +/* + * Increase resolution of cpu_power calculations + */ +#define SCHED_POWER_SHIFT 10 +#define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) + +/* + * sched-domains (multiprocessor balancing) declarations: + */ +#ifdef CONFIG_SMP +#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ +#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ +#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ +#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ +#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ +#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ +#define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */ +#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ +#define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */ +#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ +#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ +#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ +#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ +#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ + +enum powersavings_balance_level { + POWERSAVINGS_BALANCE_NONE = 0, /* No power saving load balance */ + POWERSAVINGS_BALANCE_BASIC, /* Fill one thread/core/package + * first for long running threads + */ + POWERSAVINGS_BALANCE_WAKEUP, /* Also bias task wakeups to semi-idle + * cpu package for power savings + */ + MAX_POWERSAVINGS_BALANCE_LEVELS +}; + +extern int sched_mc_power_savings, sched_smt_power_savings; + +static inline int sd_balance_for_mc_power(void) +{ + if (sched_smt_power_savings) + return SD_POWERSAVINGS_BALANCE; + + if (!sched_mc_power_savings) + return SD_PREFER_SIBLING; + + return 0; +} + +static inline int sd_balance_for_package_power(void) +{ + if (sched_mc_power_savings | sched_smt_power_savings) + return SD_POWERSAVINGS_BALANCE; + + return SD_PREFER_SIBLING; +} + +extern int __weak arch_sd_sibiling_asym_packing(void); + +/* + * Optimise SD flags for power savings: + * SD_BALANCE_NEWIDLE helps aggressive task consolidation and power savings. + * Keep default SD flags if sched_{smt,mc}_power_saving=0 + */ + +static inline int sd_power_saving_flags(void) +{ + if (sched_mc_power_savings | sched_smt_power_savings) + return SD_BALANCE_NEWIDLE; + + return 0; +} + +struct sched_group_power { + atomic_t ref; + /* + * CPU power of this group, SCHED_LOAD_SCALE being max power for a + * single CPU. + */ + unsigned int power, power_orig; + unsigned long next_update; + /* + * Number of busy cpus in this group. + */ + atomic_t nr_busy_cpus; +}; + +struct sched_group { + struct sched_group *next; /* Must be a circular list */ + atomic_t ref; + + unsigned int group_weight; + struct sched_group_power *sgp; + + /* + * The CPUs this group covers. + * + * NOTE: this field is variable length. (Allocated dynamically + * by attaching extra space to the end of the structure, + * depending on how many CPUs the kernel has booted up with) + */ + unsigned long cpumask[0]; +}; + +static inline struct cpumask *sched_group_cpus(struct sched_group *sg) +{ + return to_cpumask(sg->cpumask); +} + +/** + * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. + * @group: The group whose first cpu is to be returned. + */ +static inline unsigned int group_first_cpu(struct sched_group *group) +{ + return cpumask_first(sched_group_cpus(group)); +} + +struct sched_domain_attr { + int relax_domain_level; +}; + +#define SD_ATTR_INIT (struct sched_domain_attr) { \ + .relax_domain_level = -1, \ +} + +extern int sched_domain_level_max; + +struct sched_domain { + /* These fields must be setup */ + struct sched_domain *parent; /* top domain must be null terminated */ + struct sched_domain *child; /* bottom domain must be null terminated */ + struct sched_group *groups; /* the balancing groups of the domain */ + unsigned long min_interval; /* Minimum balance interval ms */ + unsigned long max_interval; /* Maximum balance interval ms */ + unsigned int busy_factor; /* less balancing by factor if busy */ + unsigned int imbalance_pct; /* No balance until over watermark */ + unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ + unsigned int busy_idx; + unsigned int idle_idx; + unsigned int newidle_idx; + unsigned int wake_idx; + unsigned int forkexec_idx; + unsigned int smt_gain; + int flags; /* See SD_* */ + int level; + + /* Runtime fields. */ + unsigned long last_balance; /* init to jiffies. units in jiffies */ + unsigned int balance_interval; /* initialise to 1. units in ms. */ + unsigned int nr_balance_failed; /* initialise to 0 */ + + u64 last_update; + +#ifdef CONFIG_SCHEDSTATS + /* load_balance() stats */ + unsigned int lb_count[CPU_MAX_IDLE_TYPES]; + unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; + unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; + unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; + unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; + unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; + unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; + unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; + + /* Active load balancing */ + unsigned int alb_count; + unsigned int alb_failed; + unsigned int alb_pushed; + + /* SD_BALANCE_EXEC stats */ + unsigned int sbe_count; + unsigned int sbe_balanced; + unsigned int sbe_pushed; + + /* SD_BALANCE_FORK stats */ + unsigned int sbf_count; + unsigned int sbf_balanced; + unsigned int sbf_pushed; + + /* try_to_wake_up() stats */ + unsigned int ttwu_wake_remote; + unsigned int ttwu_move_affine; + unsigned int ttwu_move_balance; +#endif +#ifdef CONFIG_SCHED_DEBUG + char *name; +#endif + union { + void *private; /* used during construction */ + struct rcu_head rcu; /* used during destruction */ + }; + + unsigned int span_weight; + /* + * Span of all CPUs in this domain. + * + * NOTE: this field is variable length. (Allocated dynamically + * by attaching extra space to the end of the structure, + * depending on how many CPUs the kernel has booted up with) + */ + unsigned long span[0]; +}; + +static inline struct cpumask *sched_domain_span(struct sched_domain *sd) +{ + return to_cpumask(sd->span); +} + +extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], + struct sched_domain_attr *dattr_new); + +/* Allocate an array of sched domains, for partition_sched_domains(). */ +cpumask_var_t *alloc_sched_domains(unsigned int ndoms); +void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); + +/* Test a flag in parent sched domain */ +static inline int test_sd_parent(struct sched_domain *sd, int flag) +{ + if (sd->parent && (sd->parent->flags & flag)) + return 1; + + return 0; +} + +unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu); +unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu); + +bool cpus_share_cache(int this_cpu, int that_cpu); + +#else /* CONFIG_SMP */ + +struct sched_domain_attr; + +static inline void +partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], + struct sched_domain_attr *dattr_new) +{ +} + +static inline bool cpus_share_cache(int this_cpu, int that_cpu) +{ + return true; +} + +#endif /* !CONFIG_SMP */ + + +struct io_context; /* See blkdev.h */ + + +#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK +extern void prefetch_stack(struct task_struct *t); +#else +static inline void prefetch_stack(struct task_struct *t) { } +#endif + +struct audit_context; /* See audit.c */ +struct mempolicy; +struct pipe_inode_info; +struct uts_namespace; + +struct rq; +struct sched_domain; + +/* + * wake flags + */ +#define WF_SYNC 0x01 /* waker goes to sleep after wakup */ +#define WF_FORK 0x02 /* child wakeup after fork */ +#define WF_MIGRATED 0x04 /* internal use, task got migrated */ + +#define ENQUEUE_WAKEUP 1 +#define ENQUEUE_HEAD 2 +#ifdef CONFIG_SMP +#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ +#else +#define ENQUEUE_WAKING 0 +#endif + +#define DEQUEUE_SLEEP 1 + +struct sched_class { + const struct sched_class *next; + + void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); + void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); + void (*yield_task) (struct rq *rq); + bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt); + + void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags); + + struct task_struct * (*pick_next_task) (struct rq *rq); + void (*put_prev_task) (struct rq *rq, struct task_struct *p); + +#ifdef CONFIG_SMP + int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags); + + void (*pre_schedule) (struct rq *this_rq, struct task_struct *task); + void (*post_schedule) (struct rq *this_rq); + void (*task_waking) (struct task_struct *task); + void (*task_woken) (struct rq *this_rq, struct task_struct *task); + + void (*set_cpus_allowed)(struct task_struct *p, + const struct cpumask *newmask); + + void (*rq_online)(struct rq *rq); + void (*rq_offline)(struct rq *rq); +#endif + + void (*set_curr_task) (struct rq *rq); + void (*task_tick) (struct rq *rq, struct task_struct *p, int queued); + void (*task_fork) (struct task_struct *p); + + void (*switched_from) (struct rq *this_rq, struct task_struct *task); + void (*switched_to) (struct rq *this_rq, struct task_struct *task); + void (*prio_changed) (struct rq *this_rq, struct task_struct *task, + int oldprio); + + unsigned int (*get_rr_interval) (struct rq *rq, + struct task_struct *task); + +#ifdef CONFIG_FAIR_GROUP_SCHED + void (*task_move_group) (struct task_struct *p, int on_rq); +#endif +}; + +struct load_weight { + unsigned long weight, inv_weight; +}; + +#ifdef CONFIG_SCHEDSTATS +struct sched_statistics { + u64 wait_start; + u64 wait_max; + u64 wait_count; + u64 wait_sum; + u64 iowait_count; + u64 iowait_sum; + + u64 sleep_start; + u64 sleep_max; + s64 sum_sleep_runtime; + + u64 block_start; + u64 block_max; + u64 exec_max; + u64 slice_max; + + u64 nr_migrations_cold; + u64 nr_failed_migrations_affine; + u64 nr_failed_migrations_running; + u64 nr_failed_migrations_hot; + u64 nr_forced_migrations; + + u64 nr_wakeups; + u64 nr_wakeups_sync; + u64 nr_wakeups_migrate; + u64 nr_wakeups_local; + u64 nr_wakeups_remote; + u64 nr_wakeups_affine; + u64 nr_wakeups_affine_attempts; + u64 nr_wakeups_passive; + u64 nr_wakeups_idle; +}; +#endif + +struct sched_entity { + struct load_weight load; /* for load-balancing */ + struct rb_node run_node; + struct list_head group_node; + unsigned int on_rq; + + u64 exec_start; + u64 sum_exec_runtime; + u64 vruntime; + u64 prev_sum_exec_runtime; + + u64 nr_migrations; + +#ifdef CONFIG_SCHEDSTATS + struct sched_statistics statistics; +#endif + +#ifdef CONFIG_FAIR_GROUP_SCHED + struct sched_entity *parent; + /* rq on which this entity is (to be) queued: */ + struct cfs_rq *cfs_rq; + /* rq "owned" by this entity/group: */ + struct cfs_rq *my_q; +#endif +}; + +struct sched_rt_entity { + struct list_head run_list; + unsigned long timeout; + unsigned int time_slice; + int nr_cpus_allowed; + + struct sched_rt_entity *back; +#ifdef CONFIG_RT_GROUP_SCHED + struct sched_rt_entity *parent; + /* rq on which this entity is (to be) queued: */ + struct rt_rq *rt_rq; + /* rq "owned" by this entity/group: */ + struct rt_rq *my_q; +#endif +}; + +/* + * default timeslice is 100 msecs (used only for SCHED_RR tasks). + * Timeslices get refilled after they expire. + */ +#define RR_TIMESLICE (100 * HZ / 1000) + +struct rcu_node; + +enum perf_event_task_context { + perf_invalid_context = -1, + perf_hw_context = 0, + perf_sw_context, + perf_nr_task_contexts, +}; + +struct task_struct { + volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ + void *stack; + atomic_t usage; + unsigned int flags; /* per process flags, defined below */ + unsigned int ptrace; + +#ifdef CONFIG_SMP + struct llist_node wake_entry; + int on_cpu; +#endif + int on_rq; + + int prio, static_prio, normal_prio; + unsigned int rt_priority; + const struct sched_class *sched_class; + struct sched_entity se; + struct sched_rt_entity rt; + +#ifdef CONFIG_PREEMPT_NOTIFIERS + /* list of struct preempt_notifier: */ + struct hlist_head preempt_notifiers; +#endif + + /* + * fpu_counter contains the number of consecutive context switches + * that the FPU is used. If this is over a threshold, the lazy fpu + * saving becomes unlazy to save the trap. This is an unsigned char + * so that after 256 times the counter wraps and the behavior turns + * lazy again; this to deal with bursty apps that only use FPU for + * a short time + */ + unsigned char fpu_counter; +#ifdef CONFIG_BLK_DEV_IO_TRACE + unsigned int btrace_seq; +#endif + + unsigned int policy; + cpumask_t cpus_allowed; + +#ifdef CONFIG_PREEMPT_RCU + int rcu_read_lock_nesting; + char rcu_read_unlock_special; + struct list_head rcu_node_entry; +#endif /* #ifdef CONFIG_PREEMPT_RCU */ +#ifdef CONFIG_TREE_PREEMPT_RCU + struct rcu_node *rcu_blocked_node; +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ +#ifdef CONFIG_RCU_BOOST + struct rt_mutex *rcu_boost_mutex; +#endif /* #ifdef CONFIG_RCU_BOOST */ + +#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) + struct sched_info sched_info; +#endif + + struct list_head tasks; +#ifdef CONFIG_SMP + struct plist_node pushable_tasks; +#endif + + struct mm_struct *mm, *active_mm; +#ifdef CONFIG_COMPAT_BRK + unsigned brk_randomized:1; +#endif +#if defined(SPLIT_RSS_COUNTING) + struct task_rss_stat rss_stat; +#endif +/* task state */ + int exit_state; + int exit_code, exit_signal; + int pdeath_signal; /* The signal sent when the parent dies */ + unsigned int jobctl; /* JOBCTL_*, siglock protected */ + /* ??? */ + unsigned int personality; + unsigned did_exec:1; + unsigned in_execve:1; /* Tell the LSMs that the process is doing an + * execve */ + unsigned in_iowait:1; + + + /* Revert to default priority/policy when forking */ + unsigned sched_reset_on_fork:1; + unsigned sched_contributes_to_load:1; + +#ifdef CONFIG_GENERIC_HARDIRQS + /* IRQ handler threads */ + unsigned irq_thread:1; +#endif + + pid_t pid; + pid_t tgid; + +#ifdef CONFIG_CC_STACKPROTECTOR + /* Canary value for the -fstack-protector gcc feature */ + unsigned long stack_canary; +#endif + + /* + * pointers to (original) parent process, youngest child, younger sibling, + * older sibling, respectively. (p->father can be replaced with + * p->real_parent->pid) + */ + struct task_struct __rcu *real_parent; /* real parent process */ + struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ + /* + * children/sibling forms the list of my natural children + */ + struct list_head children; /* list of my children */ + struct list_head sibling; /* linkage in my parent's children list */ + struct task_struct *group_leader; /* threadgroup leader */ + + /* + * ptraced is the list of tasks this task is using ptrace on. + * This includes both natural children and PTRACE_ATTACH targets. + * p->ptrace_entry is p's link on the p->parent->ptraced list. + */ + struct list_head ptraced; + struct list_head ptrace_entry; + + /* PID/PID hash table linkage. */ + struct pid_link pids[PIDTYPE_MAX]; + struct list_head thread_group; + + struct completion *vfork_done; /* for vfork() */ + int __user *set_child_tid; /* CLONE_CHILD_SETTID */ + int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ + + cputime_t utime, stime, utimescaled, stimescaled; + cputime_t gtime; +#ifndef CONFIG_VIRT_CPU_ACCOUNTING + cputime_t prev_utime, prev_stime; +#endif + unsigned long nvcsw, nivcsw; /* context switch counts */ + struct timespec start_time; /* monotonic time */ + struct timespec real_start_time; /* boot based time */ +/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ + unsigned long min_flt, maj_flt; + + struct task_cputime cputime_expires; + struct list_head cpu_timers[3]; + +/* process credentials */ + const struct cred __rcu *real_cred; /* objective and real subjective task + * credentials (COW) */ + const struct cred __rcu *cred; /* effective (overridable) subjective task + * credentials (COW) */ + struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */ + + char comm[TASK_COMM_LEN]; /* executable name excluding path + - access with [gs]et_task_comm (which lock + it with task_lock()) + - initialized normally by setup_new_exec */ +/* file system info */ + int link_count, total_link_count; +#ifdef CONFIG_SYSVIPC +/* ipc stuff */ + struct sysv_sem sysvsem; +#endif +#ifdef CONFIG_DETECT_HUNG_TASK +/* hung task detection */ + unsigned long last_switch_count; +#endif +/* CPU-specific state of this task */ + struct thread_struct thread; +/* filesystem information */ + struct fs_struct *fs; +/* open file information */ + struct files_struct *files; +/* namespaces */ + struct nsproxy *nsproxy; +/* signal handlers */ + struct signal_struct *signal; + struct sighand_struct *sighand; + + sigset_t blocked, real_blocked; + sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ + struct sigpending pending; + + unsigned long sas_ss_sp; + size_t sas_ss_size; + int (*notifier)(void *priv); + void *notifier_data; + sigset_t *notifier_mask; + struct audit_context *audit_context; +#ifdef CONFIG_AUDITSYSCALL + uid_t loginuid; + unsigned int sessionid; +#endif + seccomp_t seccomp; + +/* Thread group tracking */ + u32 parent_exec_id; + u32 self_exec_id; +/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, + * mempolicy */ + spinlock_t alloc_lock; + + /* Protection of the PI data structures: */ + raw_spinlock_t pi_lock; + +#ifdef CONFIG_RT_MUTEXES + /* PI waiters blocked on a rt_mutex held by this task */ + struct plist_head pi_waiters; + /* Deadlock detection and priority inheritance handling */ + struct rt_mutex_waiter *pi_blocked_on; +#endif + +#ifdef CONFIG_DEBUG_MUTEXES + /* mutex deadlock detection */ + struct mutex_waiter *blocked_on; +#endif +#ifdef CONFIG_TRACE_IRQFLAGS + unsigned int irq_events; + unsigned long hardirq_enable_ip; + unsigned long hardirq_disable_ip; + unsigned int hardirq_enable_event; + unsigned int hardirq_disable_event; + int hardirqs_enabled; + int hardirq_context; + unsigned long softirq_disable_ip; + unsigned long softirq_enable_ip; + unsigned int softirq_disable_event; + unsigned int softirq_enable_event; + int softirqs_enabled; + int softirq_context; +#endif +#ifdef CONFIG_LOCKDEP +# define MAX_LOCK_DEPTH 48UL + u64 curr_chain_key; + int lockdep_depth; + unsigned int lockdep_recursion; + struct held_lock held_locks[MAX_LOCK_DEPTH]; + gfp_t lockdep_reclaim_gfp; +#endif + +/* journalling filesystem info */ + void *journal_info; + +/* stacked block device info */ + struct bio_list *bio_list; + +#ifdef CONFIG_BLOCK +/* stack plugging */ + struct blk_plug *plug; +#endif + +/* VM state */ + struct reclaim_state *reclaim_state; + + struct backing_dev_info *backing_dev_info; + + struct io_context *io_context; + + unsigned long ptrace_message; + siginfo_t *last_siginfo; /* For ptrace use. */ + struct task_io_accounting ioac; +#if defined(CONFIG_TASK_XACCT) + u64 acct_rss_mem1; /* accumulated rss usage */ + u64 acct_vm_mem1; /* accumulated virtual memory usage */ + cputime_t acct_timexpd; /* stime + utime since last update */ +#endif +#ifdef CONFIG_CPUSETS + nodemask_t mems_allowed; /* Protected by alloc_lock */ + seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ + int cpuset_mem_spread_rotor; + int cpuset_slab_spread_rotor; +#endif +#ifdef CONFIG_CGROUPS + /* Control Group info protected by css_set_lock */ + struct css_set __rcu *cgroups; + /* cg_list protected by css_set_lock and tsk->alloc_lock */ + struct list_head cg_list; +#endif +#ifdef CONFIG_FUTEX + struct robust_list_head __user *robust_list; +#ifdef CONFIG_COMPAT + struct compat_robust_list_head __user *compat_robust_list; +#endif + struct list_head pi_state_list; + struct futex_pi_state *pi_state_cache; +#endif +#ifdef CONFIG_PERF_EVENTS + struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; + struct mutex perf_event_mutex; + struct list_head perf_event_list; +#endif +#ifdef CONFIG_NUMA + struct mempolicy *mempolicy; /* Protected by alloc_lock */ + short il_next; + short pref_node_fork; +#endif + struct rcu_head rcu; + + /* + * cache last used pipe for splice + */ + struct pipe_inode_info *splice_pipe; +#ifdef CONFIG_TASK_DELAY_ACCT + struct task_delay_info *delays; +#endif +#ifdef CONFIG_FAULT_INJECTION + int make_it_fail; +#endif + /* + * when (nr_dirtied >= nr_dirtied_pause), it's time to call + * balance_dirty_pages() for some dirty throttling pause + */ + int nr_dirtied; + int nr_dirtied_pause; + unsigned long dirty_paused_when; /* start of a write-and-pause period */ + +#ifdef CONFIG_LATENCYTOP + int latency_record_count; + struct latency_record latency_record[LT_SAVECOUNT]; +#endif + /* + * time slack values; these are used to round up poll() and + * select() etc timeout values. These are in nanoseconds. + */ + unsigned long timer_slack_ns; + unsigned long default_timer_slack_ns; + + struct list_head *scm_work_list; +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + /* Index of current stored address in ret_stack */ + int curr_ret_stack; + /* Stack of return addresses for return function tracing */ + struct ftrace_ret_stack *ret_stack; + /* time stamp for last schedule */ + unsigned long long ftrace_timestamp; + /* + * Number of functions that haven't been traced + * because of depth overrun. + */ + atomic_t trace_overrun; + /* Pause for the tracing */ + atomic_t tracing_graph_pause; +#endif +#ifdef CONFIG_TRACING + /* state flags for use by tracers */ + unsigned long trace; + /* bitmask and counter of trace recursion */ + unsigned long trace_recursion; +#endif /* CONFIG_TRACING */ +#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */ + struct memcg_batch_info { + int do_batch; /* incremented when batch uncharge started */ + struct mem_cgroup *memcg; /* target memcg of uncharge */ + unsigned long nr_pages; /* uncharged usage */ + unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ + } memcg_batch; +#endif +#ifdef CONFIG_HAVE_HW_BREAKPOINT + atomic_t ptrace_bp_refcnt; +#endif +}; + +/* Future-safe accessor for struct task_struct's cpus_allowed. */ +#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) + +/* + * Priority of a process goes from 0..MAX_PRIO-1, valid RT + * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH + * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority + * values are inverted: lower p->prio value means higher priority. + * + * The MAX_USER_RT_PRIO value allows the actual maximum + * RT priority to be separate from the value exported to + * user-space. This allows kernel threads to set their + * priority to a value higher than any user task. Note: + * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. + */ + +#define MAX_USER_RT_PRIO 100 +#define MAX_RT_PRIO MAX_USER_RT_PRIO + +#define MAX_PRIO (MAX_RT_PRIO + 40) +#define DEFAULT_PRIO (MAX_RT_PRIO + 20) + +static inline int rt_prio(int prio) +{ + if (unlikely(prio < MAX_RT_PRIO)) + return 1; + return 0; +} + +static inline int rt_task(struct task_struct *p) +{ + return rt_prio(p->prio); +} + +static inline struct pid *task_pid(struct task_struct *task) +{ + return task->pids[PIDTYPE_PID].pid; +} + +static inline struct pid *task_tgid(struct task_struct *task) +{ + return task->group_leader->pids[PIDTYPE_PID].pid; +} + +/* + * Without tasklist or rcu lock it is not safe to dereference + * the result of task_pgrp/task_session even if task == current, + * we can race with another thread doing sys_setsid/sys_setpgid. + */ +static inline struct pid *task_pgrp(struct task_struct *task) +{ + return task->group_leader->pids[PIDTYPE_PGID].pid; +} + +static inline struct pid *task_session(struct task_struct *task) +{ + return task->group_leader->pids[PIDTYPE_SID].pid; +} + +struct pid_namespace; + +/* + * the helpers to get the task's different pids as they are seen + * from various namespaces + * + * task_xid_nr() : global id, i.e. the id seen from the init namespace; + * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of + * current. + * task_xid_nr_ns() : id seen from the ns specified; + * + * set_task_vxid() : assigns a virtual id to a task; + * + * see also pid_nr() etc in include/linux/pid.h + */ +pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, + struct pid_namespace *ns); + +static inline pid_t task_pid_nr(struct task_struct *tsk) +{ + return tsk->pid; +} + +static inline pid_t task_pid_nr_ns(struct task_struct *tsk, + struct pid_namespace *ns) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); +} + +static inline pid_t task_pid_vnr(struct task_struct *tsk) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); +} + + +static inline pid_t task_tgid_nr(struct task_struct *tsk) +{ + return tsk->tgid; +} + +pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); + +static inline pid_t task_tgid_vnr(struct task_struct *tsk) +{ + return pid_vnr(task_tgid(tsk)); +} + + +static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, + struct pid_namespace *ns) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); +} + +static inline pid_t task_pgrp_vnr(struct task_struct *tsk) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); +} + + +static inline pid_t task_session_nr_ns(struct task_struct *tsk, + struct pid_namespace *ns) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); +} + +static inline pid_t task_session_vnr(struct task_struct *tsk) +{ + return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); +} + +/* obsolete, do not use */ +static inline pid_t task_pgrp_nr(struct task_struct *tsk) +{ + return task_pgrp_nr_ns(tsk, &init_pid_ns); +} + +/** + * pid_alive - check that a task structure is not stale + * @p: Task structure to be checked. + * + * Test if a process is not yet dead (at most zombie state) + * If pid_alive fails, then pointers within the task structure + * can be stale and must not be dereferenced. + */ +static inline int pid_alive(struct task_struct *p) +{ + return p->pids[PIDTYPE_PID].pid != NULL; +} + +/** + * is_global_init - check if a task structure is init + * @tsk: Task structure to be checked. + * + * Check if a task structure is the first user space task the kernel created. + */ +static inline int is_global_init(struct task_struct *tsk) +{ + return tsk->pid == 1; +} + +/* + * is_container_init: + * check whether in the task is init in its own pid namespace. + */ +extern int is_container_init(struct task_struct *tsk); + +extern struct pid *cad_pid; + +extern void free_task(struct task_struct *tsk); +#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) + +extern void __put_task_struct(struct task_struct *t); + +static inline void put_task_struct(struct task_struct *t) +{ + if (atomic_dec_and_test(&t->usage)) + __put_task_struct(t); +} + +extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st); +extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st); + +/* + * Per process flags + */ +#define PF_EXITING 0x00000004 /* getting shut down */ +#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ +#define PF_VCPU 0x00000010 /* I'm a virtual CPU */ +#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ +#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ +#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ +#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ +#define PF_DUMPCORE 0x00000200 /* dumped core */ +#define PF_SIGNALED 0x00000400 /* killed by a signal */ +#define PF_MEMALLOC 0x00000800 /* Allocating memory */ +#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ +#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ +#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ +#define PF_FROZEN 0x00010000 /* frozen for system suspend */ +#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ +#define PF_KSWAPD 0x00040000 /* I am kswapd */ +#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ +#define PF_KTHREAD 0x00200000 /* I am a kernel thread */ +#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ +#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ +#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ +#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ +#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ +#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ +#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ +#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ +#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ + +/* + * Only the _current_ task can read/write to tsk->flags, but other + * tasks can access tsk->flags in readonly mode for example + * with tsk_used_math (like during threaded core dumping). + * There is however an exception to this rule during ptrace + * or during fork: the ptracer task is allowed to write to the + * child->flags of its traced child (same goes for fork, the parent + * can write to the child->flags), because we're guaranteed the + * child is not running and in turn not changing child->flags + * at the same time the parent does it. + */ +#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) +#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) +#define clear_used_math() clear_stopped_child_used_math(current) +#define set_used_math() set_stopped_child_used_math(current) +#define conditional_stopped_child_used_math(condition, child) \ + do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) +#define conditional_used_math(condition) \ + conditional_stopped_child_used_math(condition, current) +#define copy_to_stopped_child_used_math(child) \ + do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) +/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ +#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) +#define used_math() tsk_used_math(current) + +/* + * task->jobctl flags + */ +#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ + +#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ +#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ +#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ +#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ +#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ +#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ +#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ + +#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) +#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) +#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) +#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) +#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) +#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) +#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) + +#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) +#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) + +extern bool task_set_jobctl_pending(struct task_struct *task, + unsigned int mask); +extern void task_clear_jobctl_trapping(struct task_struct *task); +extern void task_clear_jobctl_pending(struct task_struct *task, + unsigned int mask); + +#ifdef CONFIG_PREEMPT_RCU + +#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ +#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ + +static inline void rcu_copy_process(struct task_struct *p) +{ + p->rcu_read_lock_nesting = 0; + p->rcu_read_unlock_special = 0; +#ifdef CONFIG_TREE_PREEMPT_RCU + p->rcu_blocked_node = NULL; +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ +#ifdef CONFIG_RCU_BOOST + p->rcu_boost_mutex = NULL; +#endif /* #ifdef CONFIG_RCU_BOOST */ + INIT_LIST_HEAD(&p->rcu_node_entry); +} + +#else + +static inline void rcu_copy_process(struct task_struct *p) +{ +} + +#endif + +#ifdef CONFIG_SMP +extern void do_set_cpus_allowed(struct task_struct *p, + const struct cpumask *new_mask); + +extern int set_cpus_allowed_ptr(struct task_struct *p, + const struct cpumask *new_mask); +#else +static inline void do_set_cpus_allowed(struct task_struct *p, + const struct cpumask *new_mask) +{ +} +static inline int set_cpus_allowed_ptr(struct task_struct *p, + const struct cpumask *new_mask) +{ + if (!cpumask_test_cpu(0, new_mask)) + return -EINVAL; + return 0; +} +#endif + +#ifndef CONFIG_CPUMASK_OFFSTACK +static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) +{ + return set_cpus_allowed_ptr(p, &new_mask); +} +#endif + +/* + * Do not use outside of architecture code which knows its limitations. + * + * sched_clock() has no promise of monotonicity or bounded drift between + * CPUs, use (which you should not) requires disabling IRQs. + * + * Please use one of the three interfaces below. + */ +extern unsigned long long notrace sched_clock(void); +/* + * See the comment in kernel/sched_clock.c + */ +extern u64 cpu_clock(int cpu); +extern u64 local_clock(void); +extern u64 sched_clock_cpu(int cpu); + + +extern void sched_clock_init(void); + +#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK +static inline void sched_clock_tick(void) +{ +} + +static inline void sched_clock_idle_sleep_event(void) +{ +} + +static inline void sched_clock_idle_wakeup_event(u64 delta_ns) +{ +} +#else +/* + * Architectures can set this to 1 if they have specified + * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, + * but then during bootup it turns out that sched_clock() + * is reliable after all: + */ +extern int sched_clock_stable; + +extern void sched_clock_tick(void); +extern void sched_clock_idle_sleep_event(void); +extern void sched_clock_idle_wakeup_event(u64 delta_ns); +#endif + +#ifdef CONFIG_IRQ_TIME_ACCOUNTING +/* + * An i/f to runtime opt-in for irq time accounting based off of sched_clock. + * The reason for this explicit opt-in is not to have perf penalty with + * slow sched_clocks. + */ +extern void enable_sched_clock_irqtime(void); +extern void disable_sched_clock_irqtime(void); +#else +static inline void enable_sched_clock_irqtime(void) {} +static inline void disable_sched_clock_irqtime(void) {} +#endif + +extern unsigned long long +task_sched_runtime(struct task_struct *task); + +/* sched_exec is called by processes performing an exec */ +#ifdef CONFIG_SMP +extern void sched_exec(void); +#else +#define sched_exec() {} +#endif + +extern void sched_clock_idle_sleep_event(void); +extern void sched_clock_idle_wakeup_event(u64 delta_ns); + +#ifdef CONFIG_HOTPLUG_CPU +extern void idle_task_exit(void); +#else +static inline void idle_task_exit(void) {} +#endif + +#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) +extern void wake_up_idle_cpu(int cpu); +#else +static inline void wake_up_idle_cpu(int cpu) { } +#endif + +extern unsigned int sysctl_sched_latency; +extern unsigned int sysctl_sched_min_granularity; +extern unsigned int sysctl_sched_wakeup_granularity; +extern unsigned int sysctl_sched_child_runs_first; + +enum sched_tunable_scaling { + SCHED_TUNABLESCALING_NONE, + SCHED_TUNABLESCALING_LOG, + SCHED_TUNABLESCALING_LINEAR, + SCHED_TUNABLESCALING_END, +}; +extern enum sched_tunable_scaling sysctl_sched_tunable_scaling; + +#ifdef CONFIG_SCHED_DEBUG +extern unsigned int sysctl_sched_migration_cost; +extern unsigned int sysctl_sched_nr_migrate; +extern unsigned int sysctl_sched_time_avg; +extern unsigned int sysctl_timer_migration; +extern unsigned int sysctl_sched_shares_window; + +int sched_proc_update_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *length, + loff_t *ppos); +#endif +#ifdef CONFIG_SCHED_DEBUG +static inline unsigned int get_sysctl_timer_migration(void) +{ + return sysctl_timer_migration; +} +#else +static inline unsigned int get_sysctl_timer_migration(void) +{ + return 1; +} +#endif +extern unsigned int sysctl_sched_rt_period; +extern int sysctl_sched_rt_runtime; + +int sched_rt_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos); + +#ifdef CONFIG_SCHED_AUTOGROUP +extern unsigned int sysctl_sched_autogroup_enabled; + +extern void sched_autogroup_create_attach(struct task_struct *p); +extern void sched_autogroup_detach(struct task_struct *p); +extern void sched_autogroup_fork(struct signal_struct *sig); +extern void sched_autogroup_exit(struct signal_struct *sig); +#ifdef CONFIG_PROC_FS +extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); +extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); +#endif +#else +static inline void sched_autogroup_create_attach(struct task_struct *p) { } +static inline void sched_autogroup_detach(struct task_struct *p) { } +static inline void sched_autogroup_fork(struct signal_struct *sig) { } +static inline void sched_autogroup_exit(struct signal_struct *sig) { } +#endif + +#ifdef CONFIG_CFS_BANDWIDTH +extern unsigned int sysctl_sched_cfs_bandwidth_slice; +#endif + +#ifdef CONFIG_RT_MUTEXES +extern int rt_mutex_getprio(struct task_struct *p); +extern void rt_mutex_setprio(struct task_struct *p, int prio); +extern void rt_mutex_adjust_pi(struct task_struct *p); +static inline bool tsk_is_pi_blocked(struct task_struct *tsk) +{ + return tsk->pi_blocked_on != NULL; +} +#else +static inline int rt_mutex_getprio(struct task_struct *p) +{ + return p->normal_prio; +} +# define rt_mutex_adjust_pi(p) do { } while (0) +static inline bool tsk_is_pi_blocked(struct task_struct *tsk) +{ + return false; +} +#endif + +extern bool yield_to(struct task_struct *p, bool preempt); +extern void set_user_nice(struct task_struct *p, long nice); +extern int task_prio(const struct task_struct *p); +extern int task_nice(const struct task_struct *p); +extern int can_nice(const struct task_struct *p, const int nice); +extern int task_curr(const struct task_struct *p); +extern int idle_cpu(int cpu); +extern int sched_setscheduler(struct task_struct *, int, + const struct sched_param *); +extern int sched_setscheduler_nocheck(struct task_struct *, int, + const struct sched_param *); +extern struct task_struct *idle_task(int cpu); +/** + * is_idle_task - is the specified task an idle task? + * @p: the task in question. + */ +static inline bool is_idle_task(const struct task_struct *p) +{ + return p->pid == 0; +} +extern struct task_struct *curr_task(int cpu); +extern void set_curr_task(int cpu, struct task_struct *p); + +void yield(void); + +/* + * The default (Linux) execution domain. + */ +extern struct exec_domain default_exec_domain; + +union thread_union { + struct thread_info thread_info; + unsigned long stack[THREAD_SIZE/sizeof(long)]; +}; + +#ifndef __HAVE_ARCH_KSTACK_END +static inline int kstack_end(void *addr) +{ + /* Reliable end of stack detection: + * Some APM bios versions misalign the stack + */ + return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); +} +#endif + +extern union thread_union init_thread_union; +extern struct task_struct init_task; + +extern struct mm_struct init_mm; + +extern struct pid_namespace init_pid_ns; + +/* + * find a task by one of its numerical ids + * + * find_task_by_pid_ns(): + * finds a task by its pid in the specified namespace + * find_task_by_vpid(): + * finds a task by its virtual pid + * + * see also find_vpid() etc in include/linux/pid.h + */ + +extern struct task_struct *find_task_by_vpid(pid_t nr); +extern struct task_struct *find_task_by_pid_ns(pid_t nr, + struct pid_namespace *ns); + +extern void __set_special_pids(struct pid *pid); + +/* per-UID process charging. */ +extern struct user_struct * alloc_uid(struct user_namespace *, uid_t); +static inline struct user_struct *get_uid(struct user_struct *u) +{ + atomic_inc(&u->__count); + return u; +} +extern void free_uid(struct user_struct *); +extern void release_uids(struct user_namespace *ns); + +#include <asm/current.h> + +extern void xtime_update(unsigned long ticks); + +extern int wake_up_state(struct task_struct *tsk, unsigned int state); +extern int wake_up_process(struct task_struct *tsk); +extern void wake_up_new_task(struct task_struct *tsk); +#ifdef CONFIG_SMP + extern void kick_process(struct task_struct *tsk); +#else + static inline void kick_process(struct task_struct *tsk) { } +#endif +extern void sched_fork(struct task_struct *p); +extern void sched_dead(struct task_struct *p); + +extern void proc_caches_init(void); +extern void flush_signals(struct task_struct *); +extern void __flush_signals(struct task_struct *); +extern void ignore_signals(struct task_struct *); +extern void flush_signal_handlers(struct task_struct *, int force_default); +extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); + +static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&tsk->sighand->siglock, flags); + ret = dequeue_signal(tsk, mask, info); + spin_unlock_irqrestore(&tsk->sighand->siglock, flags); + + return ret; +} + +extern void block_all_signals(int (*notifier)(void *priv), void *priv, + sigset_t *mask); +extern void unblock_all_signals(void); +extern void release_task(struct task_struct * p); +extern int send_sig_info(int, struct siginfo *, struct task_struct *); +extern int force_sigsegv(int, struct task_struct *); +extern int force_sig_info(int, struct siginfo *, struct task_struct *); +extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); +extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); +extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, + const struct cred *, u32); +extern int kill_pgrp(struct pid *pid, int sig, int priv); +extern int kill_pid(struct pid *pid, int sig, int priv); +extern int kill_proc_info(int, struct siginfo *, pid_t); +extern __must_check bool do_notify_parent(struct task_struct *, int); +extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); +extern void force_sig(int, struct task_struct *); +extern int send_sig(int, struct task_struct *, int); +extern int zap_other_threads(struct task_struct *p); +extern struct sigqueue *sigqueue_alloc(void); +extern void sigqueue_free(struct sigqueue *); +extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); +extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); +extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long); + +static inline int kill_cad_pid(int sig, int priv) +{ + return kill_pid(cad_pid, sig, priv); +} + +/* These can be the second arg to send_sig_info/send_group_sig_info. */ +#define SEND_SIG_NOINFO ((struct siginfo *) 0) +#define SEND_SIG_PRIV ((struct siginfo *) 1) +#define SEND_SIG_FORCED ((struct siginfo *) 2) + +/* + * True if we are on the alternate signal stack. + */ +static inline int on_sig_stack(unsigned long sp) +{ +#ifdef CONFIG_STACK_GROWSUP + return sp >= current->sas_ss_sp && + sp - current->sas_ss_sp < current->sas_ss_size; +#else + return sp > current->sas_ss_sp && + sp - current->sas_ss_sp <= current->sas_ss_size; +#endif +} + +static inline int sas_ss_flags(unsigned long sp) +{ + return (current->sas_ss_size == 0 ? SS_DISABLE + : on_sig_stack(sp) ? SS_ONSTACK : 0); +} + +/* + * Routines for handling mm_structs + */ +extern struct mm_struct * mm_alloc(void); + +/* mmdrop drops the mm and the page tables */ +extern void __mmdrop(struct mm_struct *); +static inline void mmdrop(struct mm_struct * mm) +{ + if (unlikely(atomic_dec_and_test(&mm->mm_count))) + __mmdrop(mm); +} + +/* mmput gets rid of the mappings and all user-space */ +extern void mmput(struct mm_struct *); +/* Grab a reference to a task's mm, if it is not already going away */ +extern struct mm_struct *get_task_mm(struct task_struct *task); +/* + * Grab a reference to a task's mm, if it is not already going away + * and ptrace_may_access with the mode parameter passed to it + * succeeds. + */ +extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); +/* Remove the current tasks stale references to the old mm_struct */ +extern void mm_release(struct task_struct *, struct mm_struct *); +/* Allocate a new mm structure and copy contents from tsk->mm */ +extern struct mm_struct *dup_mm(struct task_struct *tsk); + +extern int copy_thread(unsigned long, unsigned long, unsigned long, + struct task_struct *, struct pt_regs *); +extern void flush_thread(void); +extern void exit_thread(void); + +extern void exit_files(struct task_struct *); +extern void __cleanup_sighand(struct sighand_struct *); + +extern void exit_itimers(struct signal_struct *); +extern void flush_itimer_signals(void); + +extern void do_group_exit(int); + +extern void daemonize(const char *, ...); +extern int allow_signal(int); +extern int disallow_signal(int); + +extern int do_execve(const char *, + const char __user * const __user *, + const char __user * const __user *, struct pt_regs *); +extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); +struct task_struct *fork_idle(int); + +extern void set_task_comm(struct task_struct *tsk, char *from); +extern char *get_task_comm(char *to, struct task_struct *tsk); + +#ifdef CONFIG_SMP +void scheduler_ipi(void); +extern unsigned long wait_task_inactive(struct task_struct *, long match_state); +#else +static inline void scheduler_ipi(void) { } +static inline unsigned long wait_task_inactive(struct task_struct *p, + long match_state) +{ + return 1; +} +#endif + +#define next_task(p) \ + list_entry_rcu((p)->tasks.next, struct task_struct, tasks) + +#define for_each_process(p) \ + for (p = &init_task ; (p = next_task(p)) != &init_task ; ) + +extern bool current_is_single_threaded(void); + +/* + * Careful: do_each_thread/while_each_thread is a double loop so + * 'break' will not work as expected - use goto instead. + */ +#define do_each_thread(g, t) \ + for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do + +#define while_each_thread(g, t) \ + while ((t = next_thread(t)) != g) + +static inline int get_nr_threads(struct task_struct *tsk) +{ + return tsk->signal->nr_threads; +} + +static inline bool thread_group_leader(struct task_struct *p) +{ + return p->exit_signal >= 0; +} + +/* Do to the insanities of de_thread it is possible for a process + * to have the pid of the thread group leader without actually being + * the thread group leader. For iteration through the pids in proc + * all we care about is that we have a task with the appropriate + * pid, we don't actually care if we have the right task. + */ +static inline int has_group_leader_pid(struct task_struct *p) +{ + return p->pid == p->tgid; +} + +static inline +int same_thread_group(struct task_struct *p1, struct task_struct *p2) +{ + return p1->tgid == p2->tgid; +} + +static inline struct task_struct *next_thread(const struct task_struct *p) +{ + return list_entry_rcu(p->thread_group.next, + struct task_struct, thread_group); +} + +static inline int thread_group_empty(struct task_struct *p) +{ + return list_empty(&p->thread_group); +} + +#define delay_group_leader(p) \ + (thread_group_leader(p) && !thread_group_empty(p)) + +/* + * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring + * subscriptions and synchronises with wait4(). Also used in procfs. Also + * pins the final release of task.io_context. Also protects ->cpuset and + * ->cgroup.subsys[]. And ->vfork_done. + * + * Nests both inside and outside of read_lock(&tasklist_lock). + * It must not be nested with write_lock_irq(&tasklist_lock), + * neither inside nor outside. + */ +static inline void task_lock(struct task_struct *p) +{ + spin_lock(&p->alloc_lock); +} + +static inline void task_unlock(struct task_struct *p) +{ + spin_unlock(&p->alloc_lock); +} + +extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, + unsigned long *flags); + +static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, + unsigned long *flags) +{ + struct sighand_struct *ret; + + ret = __lock_task_sighand(tsk, flags); + (void)__cond_lock(&tsk->sighand->siglock, ret); + return ret; +} + +static inline void unlock_task_sighand(struct task_struct *tsk, + unsigned long *flags) +{ + spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); +} + +#ifdef CONFIG_CGROUPS +static inline void threadgroup_change_begin(struct task_struct *tsk) +{ + down_read(&tsk->signal->group_rwsem); +} +static inline void threadgroup_change_end(struct task_struct *tsk) +{ + up_read(&tsk->signal->group_rwsem); +} + +/** + * threadgroup_lock - lock threadgroup + * @tsk: member task of the threadgroup to lock + * + * Lock the threadgroup @tsk belongs to. No new task is allowed to enter + * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or + * perform exec. This is useful for cases where the threadgroup needs to + * stay stable across blockable operations. + * + * fork and exit paths explicitly call threadgroup_change_{begin|end}() for + * synchronization. While held, no new task will be added to threadgroup + * and no existing live task will have its PF_EXITING set. + * + * During exec, a task goes and puts its thread group through unusual + * changes. After de-threading, exclusive access is assumed to resources + * which are usually shared by tasks in the same group - e.g. sighand may + * be replaced with a new one. Also, the exec'ing task takes over group + * leader role including its pid. Exclude these changes while locked by + * grabbing cred_guard_mutex which is used to synchronize exec path. + */ +static inline void threadgroup_lock(struct task_struct *tsk) +{ + /* + * exec uses exit for de-threading nesting group_rwsem inside + * cred_guard_mutex. Grab cred_guard_mutex first. + */ + mutex_lock(&tsk->signal->cred_guard_mutex); + down_write(&tsk->signal->group_rwsem); +} + +/** + * threadgroup_unlock - unlock threadgroup + * @tsk: member task of the threadgroup to unlock + * + * Reverse threadgroup_lock(). + */ +static inline void threadgroup_unlock(struct task_struct *tsk) +{ + up_write(&tsk->signal->group_rwsem); + mutex_unlock(&tsk->signal->cred_guard_mutex); +} +#else +static inline void threadgroup_change_begin(struct task_struct *tsk) {} +static inline void threadgroup_change_end(struct task_struct *tsk) {} +static inline void threadgroup_lock(struct task_struct *tsk) {} +static inline void threadgroup_unlock(struct task_struct *tsk) {} +#endif + +#ifndef __HAVE_THREAD_FUNCTIONS + +#define task_thread_info(task) ((struct thread_info *)(task)->stack) +#define task_stack_page(task) ((task)->stack) + +static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) +{ + *task_thread_info(p) = *task_thread_info(org); + task_thread_info(p)->task = p; +} + +static inline unsigned long *end_of_stack(struct task_struct *p) +{ + return (unsigned long *)(task_thread_info(p) + 1); +} + +#endif + +static inline int object_is_on_stack(void *obj) +{ + void *stack = task_stack_page(current); + + return (obj >= stack) && (obj < (stack + THREAD_SIZE)); +} + +extern void thread_info_cache_init(void); + +#ifdef CONFIG_DEBUG_STACK_USAGE +static inline unsigned long stack_not_used(struct task_struct *p) +{ + unsigned long *n = end_of_stack(p); + + do { /* Skip over canary */ + n++; + } while (!*n); + + return (unsigned long)n - (unsigned long)end_of_stack(p); +} +#endif + +/* set thread flags in other task's structures + * - see asm/thread_info.h for TIF_xxxx flags available + */ +static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) +{ + set_ti_thread_flag(task_thread_info(tsk), flag); +} + +static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) +{ + clear_ti_thread_flag(task_thread_info(tsk), flag); +} + +static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) +{ + return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); +} + +static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) +{ + return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); +} + +static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) +{ + return test_ti_thread_flag(task_thread_info(tsk), flag); +} + +static inline void set_tsk_need_resched(struct task_struct *tsk) +{ + set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); +} + +static inline void clear_tsk_need_resched(struct task_struct *tsk) +{ + clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); +} + +static inline int test_tsk_need_resched(struct task_struct *tsk) +{ + return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); +} + +static inline int restart_syscall(void) +{ + set_tsk_thread_flag(current, TIF_SIGPENDING); + return -ERESTARTNOINTR; +} + +static inline int signal_pending(struct task_struct *p) +{ + return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); +} + +static inline int __fatal_signal_pending(struct task_struct *p) +{ + return unlikely(sigismember(&p->pending.signal, SIGKILL)); +} + +static inline int fatal_signal_pending(struct task_struct *p) +{ + return signal_pending(p) && __fatal_signal_pending(p); +} + +static inline int signal_pending_state(long state, struct task_struct *p) +{ + if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) + return 0; + if (!signal_pending(p)) + return 0; + + return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); +} + +static inline int need_resched(void) +{ + return unlikely(test_thread_flag(TIF_NEED_RESCHED)); +} + +/* + * cond_resched() and cond_resched_lock(): latency reduction via + * explicit rescheduling in places that are safe. The return + * value indicates whether a reschedule was done in fact. + * cond_resched_lock() will drop the spinlock before scheduling, + * cond_resched_softirq() will enable bhs before scheduling. + */ +extern int _cond_resched(void); + +#define cond_resched() ({ \ + __might_sleep(__FILE__, __LINE__, 0); \ + _cond_resched(); \ +}) + +extern int __cond_resched_lock(spinlock_t *lock); + +#ifdef CONFIG_PREEMPT_COUNT +#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET +#else +#define PREEMPT_LOCK_OFFSET 0 +#endif + +#define cond_resched_lock(lock) ({ \ + __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ + __cond_resched_lock(lock); \ +}) + +extern int __cond_resched_softirq(void); + +#define cond_resched_softirq() ({ \ + __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ + __cond_resched_softirq(); \ +}) + +/* + * Does a critical section need to be broken due to another + * task waiting?: (technically does not depend on CONFIG_PREEMPT, + * but a general need for low latency) + */ +static inline int spin_needbreak(spinlock_t *lock) +{ +#ifdef CONFIG_PREEMPT + return spin_is_contended(lock); +#else + return 0; +#endif +} + +/* + * Thread group CPU time accounting. + */ +void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); +void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); + +static inline void thread_group_cputime_init(struct signal_struct *sig) +{ + raw_spin_lock_init(&sig->cputimer.lock); +} + +/* + * Reevaluate whether the task has signals pending delivery. + * Wake the task if so. + * This is required every time the blocked sigset_t changes. + * callers must hold sighand->siglock. + */ +extern void recalc_sigpending_and_wake(struct task_struct *t); +extern void recalc_sigpending(void); + +extern void signal_wake_up(struct task_struct *t, int resume_stopped); + +/* + * Wrappers for p->thread_info->cpu access. No-op on UP. + */ +#ifdef CONFIG_SMP + +static inline unsigned int task_cpu(const struct task_struct *p) +{ + return task_thread_info(p)->cpu; +} + +extern void set_task_cpu(struct task_struct *p, unsigned int cpu); + +#else + +static inline unsigned int task_cpu(const struct task_struct *p) +{ + return 0; +} + +static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) +{ +} + +#endif /* CONFIG_SMP */ + +extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); +extern long sched_getaffinity(pid_t pid, struct cpumask *mask); + +extern void normalize_rt_tasks(void); + +#ifdef CONFIG_CGROUP_SCHED + +extern struct task_group root_task_group; + +extern struct task_group *sched_create_group(struct task_group *parent); +extern void sched_destroy_group(struct task_group *tg); +extern void sched_move_task(struct task_struct *tsk); +#ifdef CONFIG_FAIR_GROUP_SCHED +extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); +extern unsigned long sched_group_shares(struct task_group *tg); +#endif +#ifdef CONFIG_RT_GROUP_SCHED +extern int sched_group_set_rt_runtime(struct task_group *tg, + long rt_runtime_us); +extern long sched_group_rt_runtime(struct task_group *tg); +extern int sched_group_set_rt_period(struct task_group *tg, + long rt_period_us); +extern long sched_group_rt_period(struct task_group *tg); +extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); +#endif +#endif + +extern int task_can_switch_user(struct user_struct *up, + struct task_struct *tsk); + +#ifdef CONFIG_TASK_XACCT +static inline void add_rchar(struct task_struct *tsk, ssize_t amt) +{ + tsk->ioac.rchar += amt; +} + +static inline void add_wchar(struct task_struct *tsk, ssize_t amt) +{ + tsk->ioac.wchar += amt; +} + +static inline void inc_syscr(struct task_struct *tsk) +{ + tsk->ioac.syscr++; +} + +static inline void inc_syscw(struct task_struct *tsk) +{ + tsk->ioac.syscw++; +} +#else +static inline void add_rchar(struct task_struct *tsk, ssize_t amt) +{ +} + +static inline void add_wchar(struct task_struct *tsk, ssize_t amt) +{ +} + +static inline void inc_syscr(struct task_struct *tsk) +{ +} + +static inline void inc_syscw(struct task_struct *tsk) +{ +} +#endif + +#ifndef TASK_SIZE_OF +#define TASK_SIZE_OF(tsk) TASK_SIZE +#endif + +#ifdef CONFIG_MM_OWNER +extern void mm_update_next_owner(struct mm_struct *mm); +extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); +#else +static inline void mm_update_next_owner(struct mm_struct *mm) +{ +} + +static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) +{ +} +#endif /* CONFIG_MM_OWNER */ + +static inline unsigned long task_rlimit(const struct task_struct *tsk, + unsigned int limit) +{ + return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); +} + +static inline unsigned long task_rlimit_max(const struct task_struct *tsk, + unsigned int limit) +{ + return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); +} + +static inline unsigned long rlimit(unsigned int limit) +{ + return task_rlimit(current, limit); +} + +static inline unsigned long rlimit_max(unsigned int limit) +{ + return task_rlimit_max(current, limit); +} + +#endif /* __KERNEL__ */ + +#endif diff -ruN linux-3.4.1/init/Kconfig linux-3.4.1-RIFS/init/Kconfig --- linux-3.4.1/init/Kconfig 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/init/Kconfig 2012-06-08 22:15:30.000000000 +0800 @@ -29,6 +29,18 @@ menu "General setup" +config SCHED_RIFS + bool "RIFS cpu scheduler" + ---help--- + The RIFS cpu scheduler is designed for excellent interactivity and + responsiveness. + + Currently incompatible with the Group CPU scheduler, and RCU TORTURE + TEST so these options are disabled. + + Say Y here. + default y + config EXPERIMENTAL bool "Prompt for development and/or incomplete code/drivers" ---help--- @@ -631,6 +643,7 @@ config CGROUP_CPUACCT bool "Simple CPU accounting cgroup subsystem" + depends on !SCHED_RIFS help Provides a simple Resource Controller for monitoring the total CPU consumed by the tasks in a cgroup. @@ -718,6 +731,7 @@ menuconfig CGROUP_SCHED bool "Group CPU scheduler" + depends on !SCHED_RIFS default n help This feature lets CPU scheduler recognize task groups and control CPU @@ -854,6 +868,7 @@ config SCHED_AUTOGROUP bool "Automatic process group scheduling" + depends on !SCHED_RIFS select EVENTFD select CGROUPS select CGROUP_SCHED diff -ruN linux-3.4.1/kernel/delayacct.c linux-3.4.1-RIFS/kernel/delayacct.c --- linux-3.4.1/kernel/delayacct.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/delayacct.c 2012-06-06 15:03:30.000000000 +0800 @@ -130,7 +130,7 @@ */ t1 = tsk->sched_info.pcount; t2 = tsk->sched_info.run_delay; - t3 = tsk->se.sum_exec_runtime; + t3 = tsk_seruntime(tsk); d->cpu_count += t1; diff -ruN linux-3.4.1/kernel/exit.c linux-3.4.1-RIFS/kernel/exit.c --- linux-3.4.1/kernel/exit.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/exit.c 2012-06-05 20:46:45.000000000 +0800 @@ -133,7 +133,7 @@ sig->inblock += task_io_get_inblock(tsk); sig->oublock += task_io_get_oublock(tsk); task_io_accounting_add(&sig->ioac, &tsk->ioac); - sig->sum_sched_runtime += tsk->se.sum_exec_runtime; + sig->sum_sched_runtime += tsk_seruntime(tsk); } sig->nr_threads--; diff -ruN linux-3.4.1/kernel/posix-cpu-timers.c linux-3.4.1-RIFS/kernel/posix-cpu-timers.c --- linux-3.4.1/kernel/posix-cpu-timers.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/posix-cpu-timers.c 2012-06-06 14:37:35.000000000 +0800 @@ -495,7 +495,7 @@ void posix_cpu_timers_exit(struct task_struct *tsk) { cleanup_timers(tsk->cpu_timers, - tsk->utime, tsk->stime, tsk->se.sum_exec_runtime); + tsk->utime, tsk->stime, tsk_seruntime(tsk)); } void posix_cpu_timers_exit_group(struct task_struct *tsk) @@ -504,7 +504,7 @@ cleanup_timers(tsk->signal->cpu_timers, tsk->utime + sig->utime, tsk->stime + sig->stime, - tsk->se.sum_exec_runtime + sig->sum_sched_runtime); + tsk_seruntime(tsk) + sig->sum_sched_runtime); } static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) @@ -934,7 +934,7 @@ struct cpu_timer_list *t = list_first_entry(timers, struct cpu_timer_list, entry); - if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) { + if (!--maxfire || tsk_seruntime(tsk) < t->expires.sched) { tsk->cputime_expires.sched_exp = t->expires.sched; break; } @@ -951,7 +951,7 @@ ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_max); if (hard != RLIM_INFINITY && - tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { + tsk_rttimeout(tsk) > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { /* * At the hard limit, we just die. * No need to calculate anything else now. @@ -959,7 +959,7 @@ __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); return; } - if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { + if (tsk_rttimeout(tsk) > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { /* * At the soft limit, send a SIGXCPU every second. */ @@ -1252,7 +1252,7 @@ struct task_cputime task_sample = { .utime = tsk->utime, .stime = tsk->stime, - .sum_exec_runtime = tsk->se.sum_exec_runtime + .sum_exec_runtime = tsk_seruntime(tsk) }; if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) diff -ruN linux-3.4.1/kernel/sched/Makefile linux-3.4.1-RIFS/kernel/sched/Makefile --- linux-3.4.1/kernel/sched/Makefile 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/sched/Makefile 2012-06-05 20:42:22.000000000 +0800 @@ -11,10 +11,13 @@ CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer endif +ifdef CONFIG_SCHED_RIFS +obj-y += rifs.o clock.o +else obj-y += core.o clock.o idle_task.o fair.o rt.o stop_task.o -obj-$(CONFIG_SMP) += cpupri.o obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o -obj-$(CONFIG_SCHEDSTATS) += stats.o obj-$(CONFIG_SCHED_DEBUG) += debug.o +endif +obj-$(CONFIG_SMP) += cpupri.o diff -ruN linux-3.4.1/kernel/sched/rifs.c linux-3.4.1-RIFS/kernel/sched/rifs.c --- linux-3.4.1/kernel/sched/rifs.c 1970-01-01 08:00:00.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/sched/rifs.c 2012-06-16 22:57:50.000000000 +0800 @@ -0,0 +1,6692 @@ +/* + * kernel/sched/rifs.c + * + * Kernel scheduler and related syscalls + * + * Copyright (C) 1991-2002 Linus Torvalds + * + * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and + * make semaphores SMP safe + * 1998-11-19 Implemented schedule_timeout() and related stuff + * by Andrea Arcangeli + * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar: + * hybrid priority-list and round-robin design with + * an array-switch method of distributing timeslices + * and per-CPU runqueues. Cleanups and useful suggestions + * by Davide Libenzi, preemptible kernel bits by Robert Love. + * 2003-09-03 Interactivity tuning by Con Kolivas. + * 2004-04-02 Scheduler domains code by Nick Piggin + * 2007-04-15 Work begun on replacing all interactivity tuning with a + * fair scheduling design by Con Kolivas. + * 2007-05-05 Load balancing (smp-nice) and other improvements + * by Peter Williams + * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith + * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri + * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins, + * Thomas Gleixner, Mike Kravetz + */ + +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/nmi.h> +#include <linux/init.h> +#include <asm/uaccess.h> +#include <linux/highmem.h> +#include <asm/mmu_context.h> +#include <linux/interrupt.h> +#include <linux/capability.h> +#include <linux/completion.h> +#include <linux/kernel_stat.h> +#include <linux/debug_locks.h> +#include <linux/perf_event.h> +#include <linux/security.h> +#include <linux/notifier.h> +#include <linux/profile.h> +#include <linux/freezer.h> +#include <linux/vmalloc.h> +#include <linux/blkdev.h> +#include <linux/delay.h> +#include <linux/smp.h> +#include <linux/threads.h> +#include <linux/timer.h> +#include <linux/rcupdate.h> +#include <linux/cpu.h> +#include <linux/cpuset.h> +#include <linux/cpumask.h> +#include <linux/percpu.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/syscalls.h> +#include <linux/times.h> +#include <linux/tsacct_kern.h> +#include <linux/kprobes.h> +#include <linux/delayacct.h> +#include <linux/log2.h> +#include <linux/bootmem.h> +#include <linux/ftrace.h> +#include <linux/slab.h> +#include <linux/init_task.h> +#include <linux/math64.h> + +#include <asm/switch_to.h> +#include <asm/tlb.h> +#include <asm/unistd.h> +#include <asm/mutex.h> + +#include "cpupri.h" +#include "../workqueue_sched.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/sched.h> + +#define MAX_TICK_USED (rr_interval * 3) +#define MAX_SLEEP_COUNT (rr_interval * 3) +#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO) +#define rt_task(p) rt_prio((p)->prio) +#define rt_queue(rq) rt_prio((rq)->rq_prio) +#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH)) +#define is_rt_policy(policy) ((policy) == SCHED_FIFO || \ + (policy) == SCHED_RR) +#define has_rt_policy(p) unlikely(is_rt_policy((p)->policy)) +#define idleprio_task(p) unlikely((p)->policy == SCHED_IDLEPRIO) +#define reverse(max, val) (max - val) + +/* + * Convert user-nice values [ -20 ... 0 ... 19 ] + * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], + * and back. + */ +#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20) +#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20) +#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio) + +/* + * 'User priority' is the nice value converted to something we + * can work with better when scaling various scheduler parameters, + * it's a [ 0 ... 39 ] range. + */ +#define USER_PRIO(p) ((p) - MAX_RT_PRIO) +#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) +#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) +#define SCHED_PRIO(p) ((p) + MAX_RT_PRIO) +#define STOP_PRIO (MAX_RT_PRIO - 1) + +/* + * Some helpers for converting to/from various scales. Use shifts to get + * approximate multiples of ten for less overhead. + */ +#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) +#define JIFFY_NS (1000000000 / HZ) +#define HALF_JIFFY_NS (1000000000 / HZ / 2) +#define HALF_JIFFY_US (1000000 / HZ / 2) +#define MS_TO_NS(TIME) ((TIME) << 20) +#define MS_TO_US(TIME) ((TIME) << 10) +#define NS_TO_MS(TIME) ((TIME) >> 20) +#define NS_TO_US(TIME) ((TIME) >> 10) + +#define RESCHED_US (100) /* Reschedule if less than this many μs left */ + +void print_scheduler_version(void) +{ + printk(KERN_INFO "Rotary Interactivity Favor Scheduler - RIFS By QQ:3766691.\n"); +} + +/* + * This is the time all tasks within the same priority round robin. + * Value is in ms and set to a minimum of 6ms. Scales with number of cpus. + * Tunable via /proc interface. + */ +int rr_interval __read_mostly = 6; + +/* + * 兼容。 + */ +int sched_iso_cpu __read_mostly = 0; + +/* + * time_slice for each process + */ +#define timeslice() MS_TO_US(rr_interval) + +#define get_time_slice(p) { \ + p->time_slice = timeslice(); \ +} + +/* + * The global runqueue data that all CPUs work off. Data is protected either + * by the global grq lock, or the discrete lock that precedes the data in this + * struct. + */ +struct global_rq { + raw_spinlock_t lock; + unsigned long nr_running; + unsigned long nr_uninterruptible; + unsigned long long nr_switches; + struct list_head queue[PRIO_LIMIT]; + DECLARE_BITMAP(prio_bitmap, PRIO_LIMIT + 1); +#ifdef CONFIG_SMP + unsigned long qnr; /* queued not running */ + cpumask_t cpu_idle_map; + bool idle_cpus; +#endif + int noc; /* num_online_cpus stored and updated when it changes */ +}; + +#ifdef CONFIG_SMP + +/* + * We add the notion of a root-domain which will be used to define per-domain + * variables. Each exclusive cpuset essentially defines an island domain by + * fully partitioning the member cpus from any other cpuset. Whenever a new + * exclusive cpuset is created, we also create and attach a new root-domain + * object. + * + */ +struct root_domain { + atomic_t refcount; + atomic_t rto_count; + struct rcu_head rcu; + cpumask_var_t span; + cpumask_var_t online; + + /* + * The "RT overload" flag: it gets set if a CPU has more than + * one runnable RT task. + */ + cpumask_var_t rto_mask; + struct cpupri cpupri; +}; + +/* + * By default the system creates a single root-domain with all cpus as + * members (mimicking the global state we have today). + */ +static struct root_domain def_root_domain; + +#endif /* CONFIG_SMP */ + +/* There can be only one */ +static struct global_rq grq; + +/* + * This is the main, per-CPU runqueue data structure. + * This data should only be modified by the local cpu. + */ +struct rq { + struct task_struct *curr, *idle, *stop; + struct mm_struct *prev_mm; + u64 last_run_scale; + + unsigned int rq_policy; + u64 rq_last_ran; + int rq_prio; + bool rq_running; /* There is a task running */ + + /* Accurate timekeeping data */ + u64 timekeep_clock; + unsigned long user_pc, nice_pc, irq_pc, softirq_pc, system_pc, + iowait_pc, idle_pc; + long account_pc; + atomic_t nr_iowait; + +#ifdef CONFIG_SMP + int cpu; /* cpu of this runqueue */ + bool online; + bool scaling; /* This CPU is managed by a scaling CPU freq governor */ + struct task_struct *sticky_task; + + struct root_domain *rd; + struct sched_domain *sd; + int *cpu_locality; /* CPU relative cache distance */ +#ifdef CONFIG_SCHED_SMT + bool (*siblings_idle)(int cpu); + /* See if all smt siblings are idle */ + cpumask_t smt_siblings; +#endif +#ifdef CONFIG_SCHED_MC + bool (*cache_idle)(int cpu); + /* See if all cache siblings are idle */ + cpumask_t cache_siblings; +#endif +#endif +#ifdef CONFIG_IRQ_TIME_ACCOUNTING + u64 prev_irq_time; +#endif + + u64 clock; + u64 clock_task; +}; + +DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); +static DEFINE_MUTEX(sched_hotcpu_mutex); + +#ifdef CONFIG_SMP +/* + * sched_domains_mutex serialises calls to init_sched_domains, + * detach_destroy_domains and partition_sched_domains. + */ +static DEFINE_MUTEX(sched_domains_mutex); + +/* + * By default the system creates a single root-domain with all cpus as + * members (mimicking the global state we have today). + */ +static struct root_domain def_root_domain; + +int __weak arch_sd_sibling_asym_packing(void) +{ + return 0*SD_ASYM_PACKING; +} +#endif + +#define rcu_dereference_check_sched_domain(p) \ + rcu_dereference_check((p), \ + lockdep_is_held(&sched_domains_mutex)) + +/* + * The domain tree (rq->sd) is protected by RCU's quiescent state transition. + * See detach_destroy_domains: synchronize_sched for details. + * + * The domain tree of any CPU may only be accessed from within + * preempt-disabled sections. + */ +#define for_each_domain(cpu, __sd) \ + for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent) + +static inline void update_rq_clock(struct rq *rq); + +/* + * Sanity check should sched_clock return bogus values. We make sure it does + * not appear to go backwards, and use jiffies to determine the maximum and + * minimum it could possibly have increased, and round down to the nearest + * jiffy when it falls outside this. + */ +static inline void niffy_diff(s64 *niff_diff, int jiff_diff) +{ + unsigned long min_diff, max_diff; + + if (jiff_diff > 1) + min_diff = JIFFIES_TO_NS(jiff_diff - 1); + else + min_diff = 1; + /* Round up to the nearest tick for maximum */ + max_diff = JIFFIES_TO_NS(jiff_diff + 1); + + if (unlikely(*niff_diff < min_diff || *niff_diff > max_diff)) + *niff_diff = min_diff; +} + +#ifdef CONFIG_SMP +#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) +#define this_rq() (&__get_cpu_var(runqueues)) +#define task_rq(p) cpu_rq(task_cpu(p)) +#define cpu_curr(cpu) (cpu_rq(cpu)->curr) +static inline int cpu_of(struct rq *rq) +{ + return rq->cpu; +} + +#else /* CONFIG_SMP */ +static struct rq *uprq; +#define cpu_rq(cpu) (uprq) +#define this_rq() (uprq) +#define task_rq(p) (uprq) +#define cpu_curr(cpu) ((uprq)->curr) +static inline int cpu_of(struct rq *rq) +{ + return 0; +} + +#endif +#define raw_rq() (&__raw_get_cpu_var(runqueues)) + +#include "stats.h" + +#ifndef prepare_arch_switch +# define prepare_arch_switch(next) do { } while (0) +#endif +#ifndef finish_arch_switch +# define finish_arch_switch(prev) do { } while (0) +#endif + +/* + * All common locking functions performed on grq.lock. rq->clock is local to + * the CPU accessing it so it can be modified just with interrupts disabled + * when we're not updating the time. + * Looking up task_rq must be done under grq.lock to be safe. + */ +static void update_rq_clock_task(struct rq *rq, s64 delta); + +static inline void update_rq_clock(struct rq *rq) +{ + s64 delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; + + rq->clock += delta; + update_rq_clock_task(rq, delta); +} + +static inline bool task_running(struct task_struct *p) +{ + return p->on_cpu; +} + +static inline void grq_lock(void) + __acquires(grq.lock) +{ + raw_spin_lock(&grq.lock); +} + +static inline void grq_unlock(void) + __releases(grq.lock) +{ + raw_spin_unlock(&grq.lock); +} + +static inline void grq_lock_irq(void) + __acquires(grq.lock) +{ + raw_spin_lock_irq(&grq.lock); +} + +static inline void time_lock_grq(struct rq *rq) + __acquires(grq.lock) +{ + grq_lock(); +} + +static inline void grq_unlock_irq(void) + __releases(grq.lock) +{ + raw_spin_unlock_irq(&grq.lock); +} + +static inline void grq_lock_irqsave(unsigned long *flags) + __acquires(grq.lock) +{ + raw_spin_lock_irqsave(&grq.lock, *flags); +} + +static inline void grq_unlock_irqrestore(unsigned long *flags) + __releases(grq.lock) +{ + raw_spin_unlock_irqrestore(&grq.lock, *flags); +} + +static inline struct rq +*task_grq_lock(struct task_struct *p, unsigned long *flags) + __acquires(grq.lock) +{ + grq_lock_irqsave(flags); + return task_rq(p); +} + +static inline struct rq +*time_task_grq_lock(struct task_struct *p, unsigned long *flags) + __acquires(grq.lock) +{ + struct rq *rq = task_grq_lock(p, flags); + return rq; +} + +static inline struct rq *task_grq_lock_irq(struct task_struct *p) + __acquires(grq.lock) +{ + grq_lock_irq(); + return task_rq(p); +} + +static inline void task_grq_unlock_irq(void) + __releases(grq.lock) +{ + grq_unlock_irq(); +} + +static inline void task_grq_unlock(unsigned long *flags) + __releases(grq.lock) +{ + grq_unlock_irqrestore(flags); +} + +/** + * grunqueue_is_locked + * + * Returns true if the global runqueue is locked. + * This interface allows printk to be called with the runqueue lock + * held and know whether or not it is OK to wake up the klogd. + */ +bool grunqueue_is_locked(void) +{ + return raw_spin_is_locked(&grq.lock); +} + +void grq_unlock_wait(void) + __releases(grq.lock) +{ + smp_mb(); /* spin-unlock-wait is not a full memory barrier */ + raw_spin_unlock_wait(&grq.lock); +} + +static inline void time_grq_lock(struct rq *rq, unsigned long *flags) + __acquires(grq.lock) +{ + local_irq_save(*flags); + time_lock_grq(rq); +} + +static inline struct rq *__task_grq_lock(struct task_struct *p) + __acquires(grq.lock) +{ + grq_lock(); + return task_rq(p); +} + +static inline void __task_grq_unlock(void) + __releases(grq.lock) +{ + grq_unlock(); +} + +/* + * Look for any tasks *anywhere* that are running nice 0 or better. We do + * this lockless for overhead reasons since the occasional wrong result + * is harmless. + */ +bool above_background_load(void) +{ + int cpu; + + for_each_online_cpu(cpu) { + struct task_struct *cpu_curr = cpu_rq(cpu)->curr; + + if (unlikely(!cpu_curr)) + continue; + if (PRIO_TO_NICE(cpu_curr->static_prio) < 1) { + return true; + } + } + return false; +} + +#ifndef __ARCH_WANT_UNLOCKED_CTXSW +static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) +{ +} + +static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) +{ +#ifdef CONFIG_DEBUG_SPINLOCK + /* this is a valid case when another task releases the spinlock */ + grq.lock.owner = current; +#endif + /* + * If we are tracking spinlock dependencies then we have to + * fix up the runqueue lock - which gets 'carried over' from + * prev into current: + */ + spin_acquire(&grq.lock.dep_map, 0, 0, _THIS_IP_); + + grq_unlock_irq(); +} + +#else /* __ARCH_WANT_UNLOCKED_CTXSW */ + +static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) +{ +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + grq_unlock_irq(); +#else + grq_unlock(); +#endif +} + +static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) +{ + smp_wmb(); +#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW + local_irq_enable(); +#endif +} +#endif /* __ARCH_WANT_UNLOCKED_CTXSW */ + +/* + * A task that is queued but not running will be on the grq run list. + * A task that is not running or queued will not be on the grq run list. + * A task that is currently running will have ->on_cpu set but not on the + * grq run list. + */ +static inline bool task_queued(struct task_struct *p) +{ + return (!list_empty(&p->run_list)); +} + +/* + * Removing from the global runqueue. Enter with grq locked. + */ +static void dequeue_task(struct task_struct *p) +{ + int prio = p->prio; + list_del_init(&p->run_list); + if (list_empty(grq.queue + prio)) + __clear_bit(prio, grq.prio_bitmap); +} + +/* + * Adding to the global runqueue. Enter with grq locked. + */ +static void enqueue_task(struct task_struct *p) +{ + int prio = p->prio; + __set_bit(prio, grq.prio_bitmap); + list_add_tail(&p->run_list, grq.queue + prio); +} + +/* Only idle task does this as a real time task*/ +static inline void enqueue_task_head(struct task_struct *p) +{ + int prio = p->prio; + __set_bit(prio, grq.prio_bitmap); + list_add(&p->run_list, grq.queue + prio); +} + +static inline void requeue_task(struct task_struct *p) +{ +} + +#ifdef CONFIG_SMP +/* + * qnr is the "queued but not running" count which is the total number of + * tasks on the global runqueue list waiting for cpu time but not actually + * currently running on a cpu. + */ +static inline void inc_qnr(void) +{ + grq.qnr++; +} + +static inline void dec_qnr(void) +{ + grq.qnr--; +} + +static inline int queued_notrunning(void) +{ + return grq.qnr; +} + +/* + * The cpu_idle_map stores a bitmap of all the CPUs currently idle to + * allow easy lookup of whether any suitable idle CPUs are available. + * It's cheaper to maintain a binary yes/no if there are any idle CPUs on the + * idle_cpus variable than to do a full bitmask check when we are busy. + */ +static inline void set_cpuidle_map(int cpu) +{ + if (likely(cpu_online(cpu))) { + cpu_set(cpu, grq.cpu_idle_map); + grq.idle_cpus = true; + } +} + +static inline void clear_cpuidle_map(int cpu) +{ + cpu_clear(cpu, grq.cpu_idle_map); + if (cpus_empty(grq.cpu_idle_map)) + grq.idle_cpus = false; +} + +static bool suitable_idle_cpus(struct task_struct *p) +{ + if (!grq.idle_cpus) + return false; + return (cpus_intersects(p->cpus_allowed, grq.cpu_idle_map)); +} + +#define CPUIDLE_DIFF_THREAD (1) +#define CPUIDLE_DIFF_CORE (2) +#define CPUIDLE_CACHE_BUSY (4) +#define CPUIDLE_DIFF_CPU (8) +#define CPUIDLE_THREAD_BUSY (16) +#define CPUIDLE_DIFF_NODE (32) + +static void resched_task(struct task_struct *p); + +/* + * The best idle CPU is chosen according to the CPUIDLE ranking above where the + * lowest value would give the most suitable CPU to schedule p onto next. The + * order works out to be the following: + * + * Same core, idle or busy cache, idle or busy threads + * Other core, same cache, idle or busy cache, idle threads. + * Same node, other CPU, idle cache, idle threads. + * Same node, other CPU, busy cache, idle threads. + * Other core, same cache, busy threads. + * Same node, other CPU, busy threads. + * Other node, other CPU, idle cache, idle threads. + * Other node, other CPU, busy cache, idle threads. + * Other node, other CPU, busy threads. + */ +static void +resched_best_mask(int best_cpu, struct rq *rq, cpumask_t *tmpmask) +{ + unsigned int best_ranking = CPUIDLE_DIFF_NODE | CPUIDLE_THREAD_BUSY | + CPUIDLE_DIFF_CPU | CPUIDLE_CACHE_BUSY | CPUIDLE_DIFF_CORE | + CPUIDLE_DIFF_THREAD; + int cpu_tmp; + + if (cpu_isset(best_cpu, *tmpmask)) + goto out; + + for_each_cpu_mask(cpu_tmp, *tmpmask) { + unsigned int ranking; + struct rq *tmp_rq; + + ranking = 0; + tmp_rq = cpu_rq(cpu_tmp); + +#ifdef CONFIG_NUMA + if (rq->cpu_locality[cpu_tmp] > 3) + ranking |= CPUIDLE_DIFF_NODE; + else +#endif + if (rq->cpu_locality[cpu_tmp] > 2) + ranking |= CPUIDLE_DIFF_CPU; +#ifdef CONFIG_SCHED_MC + if (rq->cpu_locality[cpu_tmp] == 2) + ranking |= CPUIDLE_DIFF_CORE; + if (!(tmp_rq->cache_idle(cpu_tmp))) + ranking |= CPUIDLE_CACHE_BUSY; +#endif +#ifdef CONFIG_SCHED_SMT + if (rq->cpu_locality[cpu_tmp] == 1) + ranking |= CPUIDLE_DIFF_THREAD; + if (!(tmp_rq->siblings_idle(cpu_tmp))) + ranking |= CPUIDLE_THREAD_BUSY; +#endif + if (ranking < best_ranking) { + best_cpu = cpu_tmp; + best_ranking = ranking; + } + } +out: + resched_task(cpu_rq(best_cpu)->curr); +} + +static void resched_best_idle(struct task_struct *p) +{ + cpumask_t tmpmask; + + cpus_and(tmpmask, p->cpus_allowed, grq.cpu_idle_map); + resched_best_mask(task_cpu(p), task_rq(p), &tmpmask); +} + +static inline void resched_suitable_idle(struct task_struct *p) +{ + if (suitable_idle_cpus(p)) + resched_best_idle(p); +} +/* + * Flags to tell us whether this CPU is running a CPU frequency governor that + * has slowed its speed or not. No locking required as the very rare wrongly + * read value would be harmless. + */ +void cpu_scaling(int cpu) +{ + cpu_rq(cpu)->scaling = true; +} + +void cpu_nonscaling(int cpu) +{ + cpu_rq(cpu)->scaling = false; +} + +static inline bool scaling_rq(struct rq *rq) +{ + return rq->scaling; +} + +static inline int locality_diff(struct task_struct *p, struct rq *rq) +{ + return rq->cpu_locality[task_cpu(p)]; +} +#else /* CONFIG_SMP */ +static inline void inc_qnr(void) +{ +} + +static inline void dec_qnr(void) +{ +} + +static inline int queued_notrunning(void) +{ + return grq.nr_running; +} + +static inline void set_cpuidle_map(int cpu) +{ +} + +static inline void clear_cpuidle_map(int cpu) +{ +} + +static inline bool suitable_idle_cpus(struct task_struct *p) +{ + return current == uprq->idle; +} + +static inline void resched_suitable_idle(struct task_struct *p) +{ +} + +void cpu_scaling(int __unused) +{ +} + +void cpu_nonscaling(int __unused) +{ +} + +/* + * Although CPUs can scale in UP, there is nowhere else for tasks to go so this + * always returns 0. + */ +static inline bool scaling_rq(struct rq *rq) +{ + return false; +} + +static inline int locality_diff(struct task_struct *p, struct rq *rq) +{ + return 0; +} +#endif /* CONFIG_SMP */ +EXPORT_SYMBOL_GPL(cpu_scaling); +EXPORT_SYMBOL_GPL(cpu_nonscaling); + +/* + * activate_idle_task - move idle task to the _front_ of runqueue. + */ +static inline void activate_idle_task(struct task_struct *p) +{ + enqueue_task_head(p); + grq.nr_running++; + inc_qnr(); +} + +/* + * activate_task - move a task to the runqueue. Enter with grq locked. + */ +static void activate_task(struct task_struct *p, struct rq *rq) +{ + /* + * Sleep time is in units of nanosecs, so shift by 20 to get a + * milliseconds-range estimation of the amount of time that the task + * spent sleeping: + */ + if (unlikely(prof_on == SLEEP_PROFILING)) { + if (p->state == TASK_UNINTERRUPTIBLE) + profile_hits(SLEEP_PROFILING, (void *)get_wchan(p), + (rq->clock - p->last_ran) >> 20); + + } + + if (task_contributes_to_load(p)) + grq.nr_uninterruptible--; + enqueue_task_head(p); + grq.nr_running++; + inc_qnr(); +} + +static inline void clear_sticky(struct task_struct *p); + +/* + * deactivate_task - If it's running, it's not on the grq and we can just + * decrement the nr_running. Enter with grq locked. + */ +static inline void deactivate_task(struct task_struct *p) +{ + if (task_contributes_to_load(p)) + grq.nr_uninterruptible++; + grq.nr_running--; + clear_sticky(p); +} + +#ifdef CONFIG_SMP +void set_task_cpu(struct task_struct *p, unsigned int cpu) +{ +#ifdef CONFIG_LOCKDEP + /* + * The caller should hold grq lock. + */ + WARN_ON_ONCE(debug_locks && !lockdep_is_held(&grq.lock)); +#endif + trace_sched_migrate_task(p, cpu); + if (task_cpu(p) != cpu) + perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, NULL, 0); + + /* + * After ->cpu is set up to a new value, task_grq_lock(p, ...) can be + * successfully executed on another CPU. We must ensure that updates of + * per-task data have been completed by this moment. + */ + smp_wmb(); + task_thread_info(p)->cpu = cpu; +} + +static inline void clear_sticky(struct task_struct *p) +{ + p->sticky = false; +} + +static inline bool task_sticky(struct task_struct *p) +{ + return p->sticky; +} + +/* Reschedule the best idle CPU that is not this one. */ +static void +resched_closest_idle(struct rq *rq, int cpu, struct task_struct *p) +{ + cpumask_t tmpmask; + + cpus_and(tmpmask, p->cpus_allowed, grq.cpu_idle_map); + cpu_clear(cpu, tmpmask); + if (cpus_empty(tmpmask)) + return; + resched_best_mask(cpu, rq, &tmpmask); +} + +/* + * We set the sticky flag on a task that is descheduled involuntarily meaning + * it is awaiting further CPU time. If the last sticky task is still sticky + * but unlucky enough to not be the next task scheduled, we unstick it and try + * to find it an idle CPU. Realtime tasks do not stick to minimise their + * latency at all times. + */ +static inline void +swap_sticky(struct rq *rq, int cpu, struct task_struct *p) +{ + if (rq->sticky_task) { + if (rq->sticky_task == p) { + p->sticky = true; + return; + } + if (task_sticky(rq->sticky_task)) { + clear_sticky(rq->sticky_task); + resched_closest_idle(rq, cpu, rq->sticky_task); + } + } + if (!rt_task(p)) { + p->sticky = true; + rq->sticky_task = p; + } else { + resched_closest_idle(rq, cpu, p); + rq->sticky_task = NULL; + } +} + +static inline void unstick_task(struct rq *rq, struct task_struct *p) +{ + rq->sticky_task = NULL; + clear_sticky(p); +} +#else +static inline void clear_sticky(struct task_struct *p) +{ +} + +static inline bool task_sticky(struct task_struct *p) +{ + return false; +} + +static inline void +swap_sticky(struct rq *rq, int cpu, struct task_struct *p) +{ +} + +static inline void unstick_task(struct rq *rq, struct task_struct *p) +{ +} +#endif + + +/* + * resched_task - mark a task 'to be rescheduled now'. + * + * On UP this means the setting of the need_resched flag, on SMP it + * might also involve a cross-CPU call to trigger the scheduler on + * the target CPU. + */ +#ifdef CONFIG_SMP + +#ifndef tsk_is_polling +#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) +#endif + +static void resched_task(struct task_struct *p) +{ + int cpu; + + assert_raw_spin_locked(&grq.lock); + + if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) + return; + + set_tsk_thread_flag(p, TIF_NEED_RESCHED); + + cpu = task_cpu(p); + if (cpu == smp_processor_id()) + return; + + /* NEED_RESCHED must be visible before we test polling */ + smp_mb(); + if (!tsk_is_polling(p)) + smp_send_reschedule(cpu); +} + +#else +static inline void resched_task(struct task_struct *p) +{ + assert_raw_spin_locked(&grq.lock); + set_tsk_need_resched(p); +} +#endif + +/** + * task_curr - is this task currently executing on a CPU? + * @p: the task in question. + */ +inline int task_curr(const struct task_struct *p) +{ + return cpu_curr(task_cpu(p)) == p; +} + +#ifdef CONFIG_SMP +struct migration_req { + struct task_struct *task; + int dest_cpu; +}; + +/* + * wait_task_inactive - wait for a thread to unschedule. + * + * If @match_state is nonzero, it's the @p->state value just checked and + * not expected to change. If it changes, i.e. @p might have woken up, + * then return zero. When we succeed in waiting for @p to be off its CPU, + * we return a positive number (its total switch count). If a second call + * a short while later returns the same number, the caller can be sure that + * @p has remained unscheduled the whole time. + * + * The caller must ensure that the task *will* unschedule sometime soon, + * else this function might spin for a *long* time. This function can't + * be called with interrupts off, or it may introduce deadlock with + * smp_call_function() if an IPI is sent by the same process we are + * waiting to become inactive. + */ +unsigned long wait_task_inactive(struct task_struct *p, long match_state) +{ + unsigned long flags; + bool running, on_rq; + unsigned long ncsw; + struct rq *rq; + + for (;;) { + /* + * We do the initial early heuristics without holding + * any task-queue locks at all. We'll only try to get + * the runqueue lock when things look like they will + * work out! In the unlikely event rq is dereferenced + * since we're lockless, grab it again. + */ +#ifdef CONFIG_SMP +retry_rq: + rq = task_rq(p); + if (unlikely(!rq)) + goto retry_rq; +#else /* CONFIG_SMP */ + rq = task_rq(p); +#endif + /* + * If the task is actively running on another CPU + * still, just relax and busy-wait without holding + * any locks. + * + * NOTE! Since we don't hold any locks, it's not + * even sure that "rq" stays as the right runqueue! + * But we don't care, since this will return false + * if the runqueue has changed and p is actually now + * running somewhere else! + */ + while (task_running(p) && p == rq->curr) { + if (match_state && unlikely(p->state != match_state)) + return 0; + cpu_relax(); + } + + /* + * Ok, time to look more closely! We need the grq + * lock now, to be *sure*. If we're wrong, we'll + * just go back and repeat. + */ + rq = task_grq_lock(p, &flags); + trace_sched_wait_task(p); + running = task_running(p); + on_rq = task_queued(p); + ncsw = 0; + if (!match_state || p->state == match_state) + ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ + task_grq_unlock(&flags); + + /* + * If it changed from the expected state, bail out now. + */ + if (unlikely(!ncsw)) + break; + + /* + * Was it really running after all now that we + * checked with the proper locks actually held? + * + * Oops. Go back and try again.. + */ + if (unlikely(running)) { + cpu_relax(); + continue; + } + + /* + * It's not enough that it's not actively running, + * it must be off the runqueue _entirely_, and not + * preempted! + * + * So if it was still runnable (but just not actively + * running right now), it's preempted, and we should + * yield - it could be a while. + */ + if (unlikely(on_rq)) { + ktime_t to = ktime_set(0, NSEC_PER_SEC / HZ); + + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_hrtimeout(&to, HRTIMER_MODE_REL); + continue; + } + + /* + * Ahh, all good. It wasn't running, and it wasn't + * runnable, which means that it will never become + * running in the future either. We're all done! + */ + break; + } + + return ncsw; +} + +/*** + * kick_process - kick a running thread to enter/exit the kernel + * @p: the to-be-kicked thread + * + * Cause a process which is running on another CPU to enter + * kernel-mode, without any delay. (to get signals handled.) + * + * NOTE: this function doesn't have to take the runqueue lock, + * because all it wants to ensure is that the remote task enters + * the kernel. If the IPI races and the task has been migrated + * to another CPU then no harm is done and the purpose has been + * achieved as well. + */ +void kick_process(struct task_struct *p) +{ + int cpu; + + preempt_disable(); + cpu = task_cpu(p); + if ((cpu != smp_processor_id()) && task_curr(p)) + smp_send_reschedule(cpu); + preempt_enable(); +} +EXPORT_SYMBOL_GPL(kick_process); +#endif + +#define rq_idle(rq) ((rq)->rq_prio == PRIO_LIMIT) + +/* + * RT tasks preempt on priority. + * NORMAL tasks preempt on sleep time length. + * SCHED_IDLEPRIO don't preempt anything else or + * between themselves, they cooperatively multitask. An idle rq scores as + * prio PRIO_LIMIT so it is always preempted. + */ +static inline bool +can_preempt(struct task_struct *p, int prio) +{ + if (p->prio <= prio) + return true; + return false; +} + +#ifdef CONFIG_SMP +#ifdef CONFIG_HOTPLUG_CPU +/* + * Check to see if there is a task that is affined only to offline CPUs but + * still wants runtime. This happens to kernel threads during suspend/halt and + * disabling of CPUs. + */ +#define cpu_online_map (*(cpumask_t *)cpu_online_mask) +static inline bool online_cpus(struct task_struct *p) +{ + return (likely(cpus_intersects(cpu_online_map, p->cpus_allowed))); +} +#else /* CONFIG_HOTPLUG_CPU */ +/* All available CPUs are always online without hotplug. */ +static inline bool online_cpus(struct task_struct *p) +{ + return true; +} +#endif + +/* + * Check to see if p can run on cpu, and if not, whether there are any online + * CPUs it can run on instead. + */ +static inline bool needs_other_cpu(struct task_struct *p, int cpu) +{ + if (unlikely(!cpu_isset(cpu, p->cpus_allowed))) + return true; + return false; +} + +/* + * When all else is equal, still prefer this_rq. + */ +static void try_preempt(struct task_struct *p, struct rq *this_rq) +{ + struct rq *highest_prio_rq = NULL; + int cpu, highest_prio = 0; + cpumask_t tmp; + + /* + * We clear the sticky flag here because for a task to have called + * try_preempt with the sticky flag enabled means some complicated + * re-scheduling has occurred and we should ignore the sticky flag. + */ + clear_sticky(p); + + if (suitable_idle_cpus(p)) { + resched_best_idle(p); + return; + } + + /* IDLEPRIO tasks never preempt anything but idle */ + if (p->policy == SCHED_IDLEPRIO) + return; + + if (likely(online_cpus(p))) + cpus_and(tmp, cpu_online_map, p->cpus_allowed); + else + return; + + for_each_cpu_mask(cpu, tmp) { + struct rq *rq; + int rq_prio; + + rq = cpu_rq(cpu); + rq_prio = rq->rq_prio; + if (rq_prio < highest_prio) + continue; + + if (rq_prio > highest_prio) { + highest_prio = rq_prio; + highest_prio_rq = rq; + } + } + + if (likely(highest_prio_rq)) { + if (can_preempt(p, highest_prio)) + resched_task(highest_prio_rq->curr); + } +} +#else /* CONFIG_SMP */ +static inline bool needs_other_cpu(struct task_struct *p, int cpu) +{ + return false; +} + +static void try_preempt(struct task_struct *p, struct rq *this_rq) +{ + if (p->policy == SCHED_IDLEPRIO) + return; + if (can_preempt(p, uprq->rq_prio)) + resched_task(current); +} +#endif /* CONFIG_SMP */ + +static void +ttwu_stat(struct task_struct *p, int cpu, int wake_flags) +{ +} + +static inline void ttwu_activate(struct task_struct *p, struct rq *rq, + bool is_sync) +{ + activate_task(p, rq); + + /* + * Sync wakeups (i.e. those types of wakeups where the waker + * has indicated that it will leave the CPU in short order) + * don't trigger a preemption if there are no idle cpus, + * instead waiting for current to deschedule. + */ + if (!is_sync || suitable_idle_cpus(p)) { + try_preempt(p, rq); + } +} + +static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, + bool success) +{ + trace_sched_wakeup(p, success); + p->state = TASK_RUNNING; + + /* + * if a worker is waking up, notify workqueue. Note that on BFS, we + * don't really know what cpu it will be, so we fake it for + * wq_worker_waking_up :/ + */ + if ((p->flags & PF_WQ_WORKER) && success) + wq_worker_waking_up(p, cpu_of(rq)); +} + +#ifdef CONFIG_SMP +void scheduler_ipi(void) +{ +} +#endif /* CONFIG_SMP */ + +/*** + * try_to_wake_up - wake up a thread + * @p: the thread to be awakened + * @state: the mask of task states that can be woken + * @wake_flags: wake modifier flags (WF_*) + * + * Put it on the run-queue if it's not already there. The "current" + * thread is always on the run-queue (except when the actual + * re-schedule is in progress), and as such you're allowed to do + * the simpler "current->state = TASK_RUNNING" to mark yourself + * runnable without the overhead of this. + * + * Returns %true if @p was woken up, %false if it was already running + * or @state didn't match @p's state. + */ +static bool try_to_wake_up(struct task_struct *p, unsigned int state, + int wake_flags) +{ + bool success = false; + unsigned long flags; + struct rq *rq; + int cpu; + + get_cpu(); + + /* This barrier is undocumented, probably for p->state? くそ */ + smp_wmb(); + + /* + * No need to do time_lock_grq as we only need to update the rq clock + * if we activate the task + */ + rq = task_grq_lock(p, &flags); + cpu = task_cpu(p); + + /* state is a volatile long, どうして、分からない */ + if (!((unsigned int)p->state & state)) + goto out_unlock; + + if (task_queued(p) || task_running(p)) + goto out_running; + + ttwu_activate(p, rq, wake_flags & WF_SYNC); + success = true; + +out_running: + ttwu_post_activation(p, rq, success); +out_unlock: + task_grq_unlock(&flags); + + ttwu_stat(p, cpu, wake_flags); + + put_cpu(); + + return success; +} + +/** + * try_to_wake_up_local - try to wake up a local task with grq lock held + * @p: the thread to be awakened + * + * Put @p on the run-queue if it's not already there. The caller must + * ensure that grq is locked and, @p is not the current task. + * grq stays locked over invocation. + */ +static void try_to_wake_up_local(struct task_struct *p) +{ + struct rq *rq = task_rq(p); + bool success = false; + + lockdep_assert_held(&grq.lock); + + if (!(p->state & TASK_NORMAL)) + return; + + if (!task_queued(p)) { + ttwu_activate(p, rq, false); + ttwu_stat(p, smp_processor_id(), 0); + success = true; + } + ttwu_post_activation(p, rq, success); +} + +/** + * wake_up_process - Wake up a specific process + * @p: The process to be woken up. + * + * Attempt to wake up the nominated process and move it to the set of runnable + * processes. Returns 1 if the process was woken up, 0 if it was already + * running. + * + * It may be assumed that this function implies a write memory barrier before + * changing the task state if and only if any tasks are woken up. + */ +int wake_up_process(struct task_struct *p) +{ + return try_to_wake_up(p, TASK_ALL, 0); +} +EXPORT_SYMBOL(wake_up_process); + +int wake_up_state(struct task_struct *p, unsigned int state) +{ + return try_to_wake_up(p, state, 0); +} + +/* + * Perform scheduler related setup for a newly forked process p. + * p is forked by current. + */ +void sched_fork(struct task_struct *p) +{ + struct task_struct *curr; + int cpu = get_cpu(); + struct rq *rq; + +#ifdef CONFIG_PREEMPT_NOTIFIERS + INIT_HLIST_HEAD(&p->preempt_notifiers); +#endif + /* + * We mark the process as running here. This guarantees that + * nobody will actually run it, and a signal or other external + * event cannot wake it up and insert it on the runqueue either. + */ + p->state = TASK_RUNNING; + set_task_cpu(p, cpu); + + p->sched_time = p->stime_pc = p->utime_pc = 0; + + /* + * Revert to default priority/policy on fork if requested. + */ + if (unlikely(p->sched_reset_on_fork)) { + if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) { + p->policy = SCHED_NORMAL; + } + + if (PRIO_TO_NICE(p->static_prio) < 0) { + p->static_prio = NICE_TO_PRIO(0); + } + + /* + * We don't need the reset flag anymore after the fork. It has + * fulfilled its duty: + */ + p->sched_reset_on_fork = 0; + } + + curr = current; + /* + * Make sure we do not leak PI boosting priority to the child. + */ + p->prio = curr->static_prio; + p->tick_used = curr->tick_used; + + INIT_LIST_HEAD(&p->run_list); +#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) + if (unlikely(sched_info_on())) + memset(&p->sched_info, 0, sizeof(p->sched_info)); +#endif + + p->on_cpu = false; + clear_sticky(p); + +#ifdef CONFIG_PREEMPT_COUNT + /* Want to start with kernel preemption disabled. */ + task_thread_info(p)->preempt_count = 1; +#endif + if (unlikely(p->policy == SCHED_FIFO)) + goto out; + /* + * Share the timeslice between parent and child, thus the + * total amount of pending timeslices in the system doesn't change, + * resulting in more scheduling fairness. If it's negative, it won't + * matter since that's the same as being 0. current's time_slice is + * actually in timeslice when it's running, as is its last_ran + * value. + */ + rq = task_grq_lock_irq(curr); + if (likely(curr->time_slice >= RESCHED_US * 2)) { + curr->time_slice /= 2; + p->time_slice = curr->time_slice; + } else { + /* + * Forking task has run out of timeslice. Reschedule it. + */ + curr->time_slice = 0; + set_tsk_need_resched(curr); + get_time_slice(p); + } + p->last_ran = rq->rq_last_ran; + task_grq_unlock_irq(); +out: + put_cpu(); +} + +/* + * wake_up_new_task - wake up a newly created task for the first time. + * + * This function will do some initial scheduler statistics housekeeping + * that must be done for every newly created context, then puts the task + * on the runqueue and wakes it. + */ +void wake_up_new_task(struct task_struct *p) +{ + struct task_struct *parent; + unsigned long flags; + struct rq *rq; + + rq = task_grq_lock(p, &flags); + p->state = TASK_RUNNING; + p->tick_used = 0; + parent = p->parent; + /* Unnecessary but small chance that the parent changed CPU */ + set_task_cpu(p, task_cpu(parent)); + activate_task(p, rq); + trace_sched_wakeup_new(p, 1); + if (rq->curr == parent && !suitable_idle_cpus(p)) { + /* + * The VM isn't cloned, so we're in a good position to + * do child-runs-first in anticipation of an exec. This + * usually avoids a lot of COW overhead. + */ + resched_task(parent); + } else + try_preempt(p, rq); + task_grq_unlock(&flags); +} + +#ifdef CONFIG_PREEMPT_NOTIFIERS + +/** + * preempt_notifier_register - tell me when current is being preempted & rescheduled + * @notifier: notifier struct to register + */ +void preempt_notifier_register(struct preempt_notifier *notifier) +{ + hlist_add_head(¬ifier->link, ¤t->preempt_notifiers); +} +EXPORT_SYMBOL_GPL(preempt_notifier_register); + +/** + * preempt_notifier_unregister - no longer interested in preemption notifications + * @notifier: notifier struct to unregister + * + * This is safe to call from within a preemption notifier. + */ +void preempt_notifier_unregister(struct preempt_notifier *notifier) +{ + hlist_del(¬ifier->link); +} +EXPORT_SYMBOL_GPL(preempt_notifier_unregister); + +static void fire_sched_in_preempt_notifiers(struct task_struct *curr) +{ + struct preempt_notifier *notifier; + struct hlist_node *node; + + hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link) + notifier->ops->sched_in(notifier, raw_smp_processor_id()); +} + +static void +fire_sched_out_preempt_notifiers(struct task_struct *curr, + struct task_struct *next) +{ + struct preempt_notifier *notifier; + struct hlist_node *node; + + hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link) + notifier->ops->sched_out(notifier, next); +} + +#else /* !CONFIG_PREEMPT_NOTIFIERS */ + +static void fire_sched_in_preempt_notifiers(struct task_struct *curr) +{ +} + +static void +fire_sched_out_preempt_notifiers(struct task_struct *curr, + struct task_struct *next) +{ +} + +#endif /* CONFIG_PREEMPT_NOTIFIERS */ + +/** + * prepare_task_switch - prepare to switch tasks + * @rq: the runqueue preparing to switch + * @next: the task we are going to switch to. + * + * This is called with the rq lock held and interrupts off. It must + * be paired with a subsequent finish_task_switch after the context + * switch. + * + * prepare_task_switch sets up locking and calls architecture specific + * hooks. + */ +static inline void +prepare_task_switch(struct rq *rq, struct task_struct *prev, + struct task_struct *next) +{ + perf_event_task_sched_out(prev, next); + fire_sched_out_preempt_notifiers(prev, next); + prepare_lock_switch(rq, next); + prepare_arch_switch(next); + trace_sched_switch(prev, next); +} + +/** + * finish_task_switch - clean up after a task-switch + * @rq: runqueue associated with task-switch + * @prev: the thread we just switched away from. + * + * finish_task_switch must be called after the context switch, paired + * with a prepare_task_switch call before the context switch. + * finish_task_switch will reconcile locking set up by prepare_task_switch, + * and do any other architecture-specific cleanup actions. + * + * Note that we may have delayed dropping an mm in context_switch(). If + * so, we finish that here outside of the runqueue lock. (Doing it + * with the lock held can cause deadlocks; see schedule() for + * details.) + */ +static inline void finish_task_switch(struct rq *rq, struct task_struct *prev) + __releases(grq.lock) +{ + struct mm_struct *mm = rq->prev_mm; + long prev_state; + + rq->prev_mm = NULL; + + /* + * A task struct has one reference for the use as "current". + * If a task dies, then it sets TASK_DEAD in tsk->state and calls + * schedule one last time. The schedule call will never return, and + * the scheduled task must drop that reference. + * The test for TASK_DEAD must occur while the runqueue locks are + * still held, otherwise prev could be scheduled on another cpu, die + * there before we look at prev->state, and then the reference would + * be dropped twice. + * Manfred Spraul <manfred@colorfullife.com> + */ + prev_state = prev->state; + finish_arch_switch(prev); +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + local_irq_disable(); +#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */ + perf_event_task_sched_in(prev, current); +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + local_irq_enable(); +#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */ + finish_lock_switch(rq, prev); + + fire_sched_in_preempt_notifiers(current); + if (mm) + mmdrop(mm); + if (unlikely(prev_state == TASK_DEAD)) { + /* + * Remove function-return probe instances associated with this + * task and put them back on the free list. + */ + kprobe_flush_task(prev); + put_task_struct(prev); + } +} + +/** + * schedule_tail - first thing a freshly forked thread must call. + * @prev: the thread we just switched away from. + */ +asmlinkage void schedule_tail(struct task_struct *prev) + __releases(grq.lock) +{ + struct rq *rq = this_rq(); + + finish_task_switch(rq, prev); +#ifdef __ARCH_WANT_UNLOCKED_CTXSW + /* In this case, finish_task_switch does not reenable preemption */ + preempt_enable(); +#endif + if (current->set_child_tid) + put_user(current->pid, current->set_child_tid); +} + +/* + * context_switch - switch to the new MM and the new + * thread's register state. + */ +static inline void +context_switch(struct rq *rq, struct task_struct *prev, + struct task_struct *next) +{ + struct mm_struct *mm, *oldmm; + + prepare_task_switch(rq, prev, next); + + mm = next->mm; + oldmm = prev->active_mm; + /* + * For paravirt, this is coupled with an exit in switch_to to + * combine the page table reload and the switch backend into + * one hypercall. + */ + arch_start_context_switch(prev); + + if (!mm) { + next->active_mm = oldmm; + atomic_inc(&oldmm->mm_count); + enter_lazy_tlb(oldmm, next); + } else + switch_mm(oldmm, mm, next); + + if (!prev->mm) { + prev->active_mm = NULL; + rq->prev_mm = oldmm; + } + /* + * Since the runqueue lock will be released by the next + * task (which is an invalid locking op but in the case + * of the scheduler it's an obvious special-case), so we + * do an early lockdep release here: + */ +#ifndef __ARCH_WANT_UNLOCKED_CTXSW + spin_release(&grq.lock.dep_map, 1, _THIS_IP_); +#endif + + /* Here we just switch the register state and the stack. */ + switch_to(prev, next, prev); + + barrier(); + /* + * this_rq must be evaluated again because prev may have moved + * CPUs since it called schedule(), thus the 'rq' on its stack + * frame will be invalid. + */ + finish_task_switch(this_rq(), prev); +} + +/* + * nr_running, nr_uninterruptible and nr_context_switches: + * + * externally visible scheduler statistics: current number of runnable + * threads, current number of uninterruptible-sleeping threads, total + * number of context switches performed since bootup. All are measured + * without grabbing the grq lock but the occasional inaccurate result + * doesn't matter so long as it's positive. + */ +unsigned long nr_running(void) +{ + long nr = grq.nr_running; + + if (unlikely(nr < 0)) + nr = 0; + return (unsigned long)nr; +} + +unsigned long nr_uninterruptible(void) +{ + long nu = grq.nr_uninterruptible; + + if (unlikely(nu < 0)) + nu = 0; + return nu; +} + +unsigned long long nr_context_switches(void) +{ + long long ns = grq.nr_switches; + + /* This is of course impossible */ + if (unlikely(ns < 0)) + ns = 1; + return (unsigned long long)ns; +} + +unsigned long nr_iowait(void) +{ + unsigned long i, sum = 0; + + for_each_possible_cpu(i) + sum += atomic_read(&cpu_rq(i)->nr_iowait); + + return sum; +} + +unsigned long nr_iowait_cpu(int cpu) +{ + struct rq *this = cpu_rq(cpu); + return atomic_read(&this->nr_iowait); +} + +unsigned long nr_active(void) +{ + return nr_running() + nr_uninterruptible(); +} + +/* Beyond a task running on this CPU, load is equal everywhere on BFS */ +unsigned long this_cpu_load(void) +{ + return this_rq()->rq_running + + ((queued_notrunning() + nr_uninterruptible()) / grq.noc); +} + +/* Variables and functions for calc_load */ +static unsigned long calc_load_update; +unsigned long avenrun[3]; +EXPORT_SYMBOL(avenrun); + +/** + * get_avenrun - get the load average array + * @loads: pointer to dest load array + * @offset: offset to add + * @shift: shift count to shift the result left + * + * These values are estimates at best, so no need for locking. + */ +void get_avenrun(unsigned long *loads, unsigned long offset, int shift) +{ + loads[0] = (avenrun[0] + offset) << shift; + loads[1] = (avenrun[1] + offset) << shift; + loads[2] = (avenrun[2] + offset) << shift; +} + +static unsigned long +calc_load(unsigned long load, unsigned long exp, unsigned long active) +{ + load *= exp; + load += active * (FIXED_1 - exp); + return load >> FSHIFT; +} + +/* + * calc_load - update the avenrun load estimates every LOAD_FREQ seconds. + */ +void calc_global_load(unsigned long ticks) +{ + long active; + + if (time_before(jiffies, calc_load_update)) + return; + active = nr_active() * FIXED_1; + + avenrun[0] = calc_load(avenrun[0], EXP_1, active); + avenrun[1] = calc_load(avenrun[1], EXP_5, active); + avenrun[2] = calc_load(avenrun[2], EXP_15, active); + + calc_load_update = jiffies + LOAD_FREQ; +} + +DEFINE_PER_CPU(struct kernel_stat, kstat); +DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat); + +EXPORT_PER_CPU_SYMBOL(kstat); +EXPORT_PER_CPU_SYMBOL(kernel_cpustat); + +#ifdef CONFIG_IRQ_TIME_ACCOUNTING + +/* + * There are no locks covering percpu hardirq/softirq time. + * They are only modified in account_system_vtime, on corresponding CPU + * with interrupts disabled. So, writes are safe. + * They are read and saved off onto struct rq in update_rq_clock(). + * This may result in other CPU reading this CPU's irq time and can + * race with irq/account_system_vtime on this CPU. We would either get old + * or new value with a side effect of accounting a slice of irq time to wrong + * task when irq is in progress while we read rq->clock. That is a worthy + * compromise in place of having locks on each irq in account_system_time. + */ +static DEFINE_PER_CPU(u64, cpu_hardirq_time); +static DEFINE_PER_CPU(u64, cpu_softirq_time); + +static DEFINE_PER_CPU(u64, irq_start_time); +static int sched_clock_irqtime; + +void enable_sched_clock_irqtime(void) +{ + sched_clock_irqtime = 1; +} + +void disable_sched_clock_irqtime(void) +{ + sched_clock_irqtime = 0; +} + +#ifndef CONFIG_64BIT +static DEFINE_PER_CPU(seqcount_t, irq_time_seq); + +static inline void irq_time_write_begin(void) +{ + __this_cpu_inc(irq_time_seq.sequence); + smp_wmb(); +} + +static inline void irq_time_write_end(void) +{ + smp_wmb(); + __this_cpu_inc(irq_time_seq.sequence); +} + +static inline u64 irq_time_read(int cpu) +{ + u64 irq_time; + unsigned seq; + + do { + seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu)); + irq_time = per_cpu(cpu_softirq_time, cpu) + + per_cpu(cpu_hardirq_time, cpu); + } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq)); + + return irq_time; +} +#else /* CONFIG_64BIT */ +static inline void irq_time_write_begin(void) +{ +} + +static inline void irq_time_write_end(void) +{ +} + +static inline u64 irq_time_read(int cpu) +{ + return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); +} +#endif /* CONFIG_64BIT */ + +bool cpus_share_cache(int this_cpu, int that_cpu) +{ + struct rq *this_rq = cpu_rq(this_cpu); + + return (this_rq->cpu_locality[that_cpu] < 2); +} +EXPORT_SYMBOL(cpus_share_cache); + +/* + * Called before incrementing preempt_count on {soft,}irq_enter + * and before decrementing preempt_count on {soft,}irq_exit. + */ +void account_system_vtime(struct task_struct *curr) +{ + unsigned long flags; + s64 delta; + int cpu; + + if (!sched_clock_irqtime) + return; + + local_irq_save(flags); + + cpu = smp_processor_id(); + delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time); + __this_cpu_add(irq_start_time, delta); + + irq_time_write_begin(); + /* + * We do not account for softirq time from ksoftirqd here. + * We want to continue accounting softirq time to ksoftirqd thread + * in that case, so as not to confuse scheduler with a special task + * that do not consume any time, but still wants to run. + */ + if (hardirq_count()) + __this_cpu_add(cpu_hardirq_time, delta); + else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) + __this_cpu_add(cpu_softirq_time, delta); + + irq_time_write_end(); + local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(account_system_vtime); + +#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ + +static void update_rq_clock_task(struct rq *rq, s64 delta) +{ +#ifdef CONFIG_IRQ_TIME_ACCOUNTING + s64 irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; + + /* + * Since irq_time is only updated on {soft,}irq_exit, we might run into + * this case when a previous update_rq_clock() happened inside a + * {soft,}irq region. + * + * When this happens, we stop ->clock_task and only update the + * prev_irq_time stamp to account for the part that fit, so that a next + * update will consume the rest. This ensures ->clock_task is + * monotonic. + * + * It does however cause some slight miss-attribution of {soft,}irq + * time, a more accurate solution would be to update the irq_time using + * the current rq->clock timestamp, except that would require using + * atomic ops. + */ + if (irq_delta > delta) + irq_delta = delta; + + rq->prev_irq_time += irq_delta; + delta -= irq_delta; +#endif + rq->clock_task += delta; +} + +#ifndef nsecs_to_cputime +# define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs) +#endif + +#ifdef CONFIG_IRQ_TIME_ACCOUNTING +static void irqtime_account_hi_si(void) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + u64 latest_ns; + + latest_ns = nsecs_to_cputime64(this_cpu_read(cpu_hardirq_time)); + if (latest_ns > cpustat[CPUTIME_IRQ]) + cpustat[CPUTIME_IRQ] += (__force u64)cputime_one_jiffy; + + latest_ns = nsecs_to_cputime64(this_cpu_read(cpu_softirq_time)); + if (latest_ns > cpustat[CPUTIME_SOFTIRQ]) + cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy; +} +#else /* CONFIG_IRQ_TIME_ACCOUNTING */ + +#define sched_clock_irqtime (0) + +static inline void irqtime_account_hi_si(void) +{ +} +#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ + +/* + * On each tick, see what percentage of that tick was attributed to each + * component and add the percentage to the _pc values. Once a _pc value has + * accumulated one tick's worth, account for that. This means the total + * percentage of load components will always be 128 (pseudo 100) per tick. + */ +static void pc_idle_time(struct rq *rq, unsigned long pc) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + + if (atomic_read(&rq->nr_iowait) > 0) { + rq->iowait_pc += pc; + if (rq->iowait_pc >= 128) { + rq->iowait_pc %= 128; + cpustat[CPUTIME_IOWAIT] += (__force u64)cputime_one_jiffy; + } + } else { + rq->idle_pc += pc; + if (rq->idle_pc >= 128) { + rq->idle_pc %= 128; + cpustat[CPUTIME_IDLE] += (__force u64)cputime_one_jiffy; + } + } +} + +static void +pc_system_time(struct rq *rq, struct task_struct *p, int hardirq_offset, + unsigned long pc, unsigned long ns) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); + + p->stime_pc += pc; + if (p->stime_pc >= 128) { + p->stime_pc %= 128; + p->stime += (__force u64)cputime_one_jiffy; + p->stimescaled += one_jiffy_scaled; + acct_update_integrals(p); + } + p->sched_time += ns; + + if (hardirq_count() - hardirq_offset) { + rq->irq_pc += pc; + if (rq->irq_pc >= 128) { + rq->irq_pc %= 128; + cpustat[CPUTIME_IRQ] += (__force u64)cputime_one_jiffy; + } + } else if (in_serving_softirq()) { + rq->softirq_pc += pc; + if (rq->softirq_pc >= 128) { + rq->softirq_pc %= 128; + cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy; + } + } else { + rq->system_pc += pc; + if (rq->system_pc >= 128) { + rq->system_pc %= 128; + cpustat[CPUTIME_SYSTEM] += (__force u64)cputime_one_jiffy; + } + } +} + +static void pc_user_time(struct rq *rq, struct task_struct *p, + unsigned long pc, unsigned long ns) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); + + p->utime_pc += pc; + if (p->utime_pc >= 128) { + p->utime_pc %= 128; + p->utime += (__force u64)cputime_one_jiffy; + p->utimescaled += one_jiffy_scaled; + acct_update_integrals(p); + } + p->sched_time += ns; + + if (this_cpu_ksoftirqd() == p) { + /* + * ksoftirqd time do not get accounted in cpu_softirq_time. + * So, we have to handle it separately here. + */ + rq->softirq_pc += pc; + if (rq->softirq_pc >= 128) { + rq->softirq_pc %= 128; + cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy; + } + } + + if (TASK_NICE(p) > 0 || idleprio_task(p)) { + rq->nice_pc += pc; + if (rq->nice_pc >= 128) { + rq->nice_pc %= 128; + cpustat[CPUTIME_NICE] += (__force u64)cputime_one_jiffy; + } + } else { + rq->user_pc += pc; + if (rq->user_pc >= 128) { + rq->user_pc %= 128; + cpustat[CPUTIME_USER] += (__force u64)cputime_one_jiffy; + } + } +} + +/* + * Convert nanoseconds to pseudo percentage of one tick. Use 128 for fast + * shifts instead of 100 + */ +#define NS_TO_PC(NS) (NS * 128 / JIFFY_NS) + +/* + * This is called on clock ticks and on context switches. + * Bank in p->sched_time the ns elapsed since the last tick or switch. + * CPU scheduler quota accounting is also performed here in microseconds. + */ +static void +update_cpu_clock(struct rq *rq, struct task_struct *p) +{ + long account_ns = rq->clock - rq->timekeep_clock; + struct task_struct *idle = rq->idle; + unsigned long account_pc; + int user_tick; + + p->last_ran = rq->clock; + + if (unlikely(account_ns < 0)) + account_ns = 0; + + account_pc = NS_TO_PC(account_ns); + + /* Accurate tick timekeeping */ + rq->account_pc += account_pc - 128; + if (rq->account_pc < 0) { + /* + * Small errors in micro accounting may not make the + * accounting add up to 128 each tick so we keep track + * of the percentage and round it up when less than 128 + */ + account_pc += -rq->account_pc; + rq->account_pc = 0; + } + + user_tick = user_mode(get_irq_regs()); + + if (user_tick) + pc_user_time(rq, p, account_pc, account_ns); + else if (p != idle || (irq_count() != HARDIRQ_OFFSET)) + pc_system_time(rq, p, HARDIRQ_OFFSET, + account_pc, account_ns); + else + pc_idle_time(rq, account_pc); + + if (sched_clock_irqtime) + irqtime_account_hi_si(); + + /* time_slice accounting is done in usecs to avoid overflow on 32bit */ + if (rq->rq_policy != SCHED_FIFO && p != idle) { + s64 time_diff = rq->clock - rq->rq_last_ran; + + niffy_diff(&time_diff, 1); + p->time_slice -= NS_TO_US(time_diff); + } + rq->rq_last_ran = rq->timekeep_clock = rq->clock; +} + +/* + * Return any ns on the sched_clock that have not yet been accounted in + * @p in case that task is currently running. + * + * Called with task_grq_lock() held. + */ +static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq) +{ + u64 ns = 0; + + if (p == rq->curr) { + ns = rq->clock_task - rq->rq_last_ran; + if (unlikely((s64)ns < 0)) + ns = 0; + } + + return ns; +} + +unsigned long long task_delta_exec(struct task_struct *p) +{ + unsigned long flags; + struct rq *rq; + u64 ns; + + rq = task_grq_lock(p, &flags); + ns = do_task_delta_exec(p, rq); + task_grq_unlock(&flags); + + return ns; +} + +/* + * Return accounted runtime for the task. + * In case the task is currently running, return the runtime plus current's + * pending runtime that have not been accounted yet. + */ +unsigned long long task_sched_runtime(struct task_struct *p) +{ + unsigned long flags; + struct rq *rq; + u64 ns; + + rq = task_grq_lock(p, &flags); + ns = p->sched_time + do_task_delta_exec(p, rq); + task_grq_unlock(&flags); + + return ns; +} + +/* Compatibility crap for removal */ +void account_user_time(struct task_struct *p, cputime_t cputime, + cputime_t cputime_scaled) +{ +} + +void account_idle_time(cputime_t cputime) +{ +} + +/* + * Account guest cpu time to a process. + * @p: the process that the cpu time gets accounted to + * @cputime: the cpu time spent in virtual machine since the last update + * @cputime_scaled: cputime scaled by cpu frequency + */ +static void account_guest_time(struct task_struct *p, cputime_t cputime, + cputime_t cputime_scaled) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + + /* Add guest time to process. */ + p->utime += (__force u64)cputime; + p->utimescaled += (__force u64)cputime_scaled; + p->gtime += (__force u64)cputime; + + /* Add guest time to cpustat. */ + if (TASK_NICE(p) > 0) { + cpustat[CPUTIME_NICE] += (__force u64)cputime; + cpustat[CPUTIME_GUEST_NICE] += (__force u64)cputime; + } else { + cpustat[CPUTIME_USER] += (__force u64)cputime; + cpustat[CPUTIME_GUEST] += (__force u64)cputime; + } +} + +/* + * Account system cpu time to a process and desired cpustat field + * @p: the process that the cpu time gets accounted to + * @cputime: the cpu time spent in kernel space since the last update + * @cputime_scaled: cputime scaled by cpu frequency + * @target_cputime64: pointer to cpustat field that has to be updated + */ +static inline +void __account_system_time(struct task_struct *p, cputime_t cputime, + cputime_t cputime_scaled, cputime64_t *target_cputime64) +{ + /* Add system time to process. */ + p->stime += (__force u64)cputime; + p->stimescaled += (__force u64)cputime_scaled; + + /* Add system time to cpustat. */ + *target_cputime64 += (__force u64)cputime; + + /* Account for system time used */ + acct_update_integrals(p); +} + +/* + * Account system cpu time to a process. + * @p: the process that the cpu time gets accounted to + * @hardirq_offset: the offset to subtract from hardirq_count() + * @cputime: the cpu time spent in kernel space since the last update + * @cputime_scaled: cputime scaled by cpu frequency + * This is for guest only now. + */ +void account_system_time(struct task_struct *p, int hardirq_offset, + cputime_t cputime, cputime_t cputime_scaled) +{ + + if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) + account_guest_time(p, cputime, cputime_scaled); +} + +/* + * Account for involuntary wait time. + * @steal: the cpu time spent in involuntary wait + */ +void account_steal_time(cputime_t cputime) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + + cpustat[CPUTIME_STEAL] += (__force u64)cputime; +} + +/* + * Account for idle time. + * @cputime: the cpu time spent in idle wait + */ +static void account_idle_times(cputime_t cputime) +{ + u64 *cpustat = kcpustat_this_cpu->cpustat; + struct rq *rq = this_rq(); + + if (atomic_read(&rq->nr_iowait) > 0) + cpustat[CPUTIME_IOWAIT] += (__force u64)cputime; + else + cpustat[CPUTIME_IDLE] += (__force u64)cputime; +} + +#ifndef CONFIG_VIRT_CPU_ACCOUNTING + +void account_process_tick(struct task_struct *p, int user_tick) +{ +} + +/* + * Account multiple ticks of steal time. + * @p: the process from which the cpu time has been stolen + * @ticks: number of stolen ticks + */ +void account_steal_ticks(unsigned long ticks) +{ + account_steal_time(jiffies_to_cputime(ticks)); +} + +/* + * Account multiple ticks of idle time. + * @ticks: number of stolen ticks + */ +void account_idle_ticks(unsigned long ticks) +{ + account_idle_times(jiffies_to_cputime(ticks)); +} +#endif + +/* This manages tasks that have run out of timeslice during a scheduler_tick */ +/* 当前队列时钟的控制 */ +static void task_running_tick(struct rq *rq) +{ + struct task_struct *p; + p = rq->curr; + + /* SCHED_FIFO tasks never run out of timeslice. */ + if (rq->rq_policy == SCHED_FIFO) + return; + if(p->tick_used <= MAX_TICK_USED) + p->tick_used++; + if (p->time_slice > RESCHED_US) + return; + + /* time_slice expired. Grq locked */ + grq_lock(); + requeue_task(p); + set_tsk_need_resched(p); + grq_unlock(); +} + +void wake_up_idle_cpu(int cpu); + +/* + * This function gets called by the timer code, with HZ frequency. + * We call it with interrupts disabled. The data modified is all + * local to struct rq so we don't need to grab grq lock. + */ +void scheduler_tick(void) +{ + int cpu __maybe_unused = smp_processor_id(); + struct rq *rq = cpu_rq(cpu); + + sched_clock_tick(); + /* grq lock not grabbed, so only update rq clock */ + update_rq_clock(rq); + update_cpu_clock(rq, rq->curr); + if (!rq_idle(rq)) + task_running_tick(rq); + perf_event_task_tick(); +} + +notrace unsigned long get_parent_ip(unsigned long addr) +{ + if (in_lock_functions(addr)) { + addr = CALLER_ADDR2; + if (in_lock_functions(addr)) + addr = CALLER_ADDR3; + } + return addr; +} + +#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ + defined(CONFIG_PREEMPT_TRACER)) +void __kprobes add_preempt_count(int val) +{ +#ifdef CONFIG_DEBUG_PREEMPT + /* + * Underflow? + */ + if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) + return; +#endif + preempt_count() += val; +#ifdef CONFIG_DEBUG_PREEMPT + /* + * Spinlock count overflowing soon? + */ + DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= + PREEMPT_MASK - 10); +#endif + if (preempt_count() == val) + trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); +} +EXPORT_SYMBOL(add_preempt_count); + +void __kprobes sub_preempt_count(int val) +{ +#ifdef CONFIG_DEBUG_PREEMPT + /* + * Underflow? + */ + if (DEBUG_LOCKS_WARN_ON(val > preempt_count())) + return; + /* + * Is the spinlock portion underflowing? + */ + if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) && + !(preempt_count() & PREEMPT_MASK))) + return; +#endif + + if (preempt_count() == val) + trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); + preempt_count() -= val; +} +EXPORT_SYMBOL(sub_preempt_count); +#endif + +#define prio_raisable(p) ( \ + p->prio > ((p->static_prio - reverse(MAX_TICK_USED, p->tick_used)) + \ + (p->sleep_cnt / 3))) + +/* + * Timeslices below RESCHED_US are considered as good as expired as there's no + * point rescheduling when there's so little time left. SCHED_BATCH tasks + * have been flagged be not latency sensitive and likely to be fully CPU + * bound so every time they're rescheduled they have their time_slice + * refilled. + */ +static inline bool check_timeslice_end(struct rq *rq, struct task_struct *p) +{ + u64 sleep_jiffy = jiffies_64; + bool preempt = false; + if (p->policy == SCHED_FIFO) + goto out; + if (p->time_slice < RESCHED_US || batch_task(p)) { + if(p->prio > MAX_RT_PRIO) { + p->prio++; + if(p->prio >= IDLE_PRIO) { + p->prio = p->static_prio + 5; + if(p->prio >= IDLE_PRIO) + p->prio = p->static_prio; + } + } + get_time_slice(p); + } else if(p->policy != SCHED_RR) { + if(p->state != TASK_RUNNING) { + if(p->prio > NORMAL_PRIO) { + if(p->sleep_cnt < MAX_SLEEP_COUNT) + p->sleep_cnt++; + if(prio_raisable(p)) + p->prio--; + if(sleep_jiffy != p->sleep_jiffy) + p->sleep_cnt /= 2; + p->sleep_jiffy = sleep_jiffy; + } + } else { + preempt = true; + } + } + if((p->state != TASK_RUNNING) || (p->tick_used >= MAX_TICK_USED)) { + p->tick_used /= 2; + } +out: + return preempt; +} + +#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) + + +/* + * 最低位查找，查找最高优先级开始。 + * Find the lowest bit set in the bitmap.We would find the highest priority first/ + */ +static inline unsigned long +get_prio_bit(unsigned long *addr, unsigned long offset) +{ + unsigned long *from = addr + (offset / BITS_PER_LONG); + unsigned long *limit = addr + PRIO_LIMIT / BITS_PER_LONG; + int i = offset % BITS_PER_LONG; + + if (offset >= PRIO_LIMIT) + return PRIO_LIMIT; + + for(;from != (limit);from++) { + for(;i < BITS_PER_LONG;i++, offset++) { + if(((*from >> i) & 0x1)) { + goto out; + } + } + + /* + * This can make sure to generate the best machine code. + */ + i = 0; + } +out: + return offset; +} + +/* + * The currently running task's information is all stored in rq local data + * which is only modified by the local CPU, thereby allowing the data to be + * changed without grabbing the grq lock. + */ +static inline void set_rq_task(struct rq *rq, struct task_struct *p) +{ + rq->rq_last_ran = p->last_ran = rq->clock; + rq->rq_policy = p->policy; + rq->rq_prio = p->prio; + if (p != rq->idle) + rq->rq_running = true; + else + rq->rq_running = false; +} + +static void reset_rq_task(struct rq *rq, struct task_struct *p) +{ + rq->rq_policy = p->policy; + rq->rq_prio = p->prio; +} + +static inline void operate_blk_needs_flush_plug(struct task_struct *p) +{ + grq_unlock_irq(); + sched_preempt_enable_no_resched(); + blk_schedule_flush_plug(p); +} + +static inline void task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) +{ + /* + * Don't stick tasks when a real time task is going to run as + * they may literally get stuck. + */ + if (rt_task(next)) + unstick_task(rq, prev); + set_rq_task(rq, next); + grq.nr_switches++; + prev->on_cpu = false; + next->on_cpu = true; + rq->curr = next; + + /* + * The context switch have flipped the stack from under us + * and restored the local variables which were saved when + * this task called schedule() in the past. prev == current + * is still correct, but it can be moved to another cpu/rq. + */ + context_switch(rq, prev, next); /* unlocks the grq */ +} + + +/* + * Move a task off the global queue and take it to a cpu for it will + * become the running task. + */ +static inline void take_task(int cpu, struct task_struct *p) +{ + set_task_cpu(p, cpu); + dequeue_task(p); + clear_sticky(p); + dec_qnr(); +} + +/* + * Put the descheduling task back to grq. + */ +static inline void put_prev_task(struct rq *rq, struct task_struct *p, bool deactivate, bool preempt) +{ + if(deactivate) + deactivate_task(p); + else { + inc_qnr(); + if(preempt) + enqueue_task_head(p); + else + enqueue_task(p); + } +} + +/* + * Task picking for next time to run. + */ +static inline struct +task_struct *get_runnable_task(struct rq *rq, int cpu, struct task_struct *idle) +{ + struct task_struct *edt = NULL; + unsigned long idx = -1; + + do { + struct list_head *queue; + struct task_struct *p; + + idx = get_prio_bit(grq.prio_bitmap, ++idx); + if (idx >= PRIO_LIMIT) + return idle; + queue = grq.queue + idx; + + list_for_each_entry(p, queue, run_list) { + /* Make sure cpu affinity is ok */ + if (needs_other_cpu(p, cpu)) + continue; + edt = p; + goto out_take; + } + } while (!edt); + +out_take: + take_task(cpu, edt); + return edt; +} + +#define SCHED_RESCHED -1 + +/* + * schedule() is the main scheduler function. + */ +static inline int check_sleep_on_wq(int cpu, struct task_struct *p) +{ + int deactivate; + deactivate = 0; + if (p->state && !(preempt_count() & PREEMPT_ACTIVE)) { + if (unlikely(signal_pending_state(p->state, p))) { + p->state = TASK_RUNNING; + } else { + deactivate = 1; + /* + * If a worker is going to sleep, notify and + * ask workqueue whether it wants to wake up a + * task to maintain concurrency. If so, wake + * up the task. + */ + if (p->flags & PF_WQ_WORKER) { + struct task_struct *to_wakeup; + + to_wakeup = wq_worker_sleeping(p, cpu); + if (to_wakeup) { + /* This shouldn't happen, but does */ + if (unlikely(to_wakeup == p)) + deactivate = 0; + else + try_to_wake_up_local(to_wakeup); + } + } + + /* + * If we are going to sleep and we have plugged IO queued, make + * sure to submit it to avoid deadlocks. + */ + if (unlikely(deactivate && blk_needs_flush_plug(p))) { + operate_blk_needs_flush_plug(p); + deactivate = SCHED_RESCHED; + goto out; + } + } + } +out: + return deactivate; +} + +static inline int do_schedule(void) +{ + struct task_struct *prev, *next, *idle; + struct rq *rq; + int cpu; + int deactivate; + + cpu = smp_processor_id(); + rq = cpu_rq(cpu); + rcu_note_context_switch(cpu); + prev = rq->curr; + + grq_lock_irq(); + + if((deactivate = check_sleep_on_wq(cpu, prev)) == SCHED_RESCHED) { + goto out; + } + + clear_tsk_need_resched(prev); + + idle = rq->idle; + if (idle != prev) { + bool preempt = check_timeslice_end(rq, prev); + + /* Task changed affinity off this CPU */ + if (needs_other_cpu(prev, cpu)) + resched_suitable_idle(prev); + else if (!deactivate) { + if (!queued_notrunning()) { + /* + * Rerun the prev task again. + */ + set_rq_task(rq, prev); + grq_unlock_irq(); + goto out; + } else + swap_sticky(rq, cpu, prev); + } + + put_prev_task(rq, prev, deactivate, preempt); + } + + if (unlikely(!queued_notrunning())) { + /* + * This CPU is now truly idle as opposed to when idle is + * scheduled as a high priority task in its own right. + */ + next = idle; + set_cpuidle_map(cpu); + } else { + next = get_runnable_task(rq, cpu, idle); + } + + if (likely(prev != next)) { + prev->nvcsw++; + grq.nr_switches++; + + task_switch(rq, prev, next); + idle = rq->idle; + } else + grq_unlock_irq(); + +out: + return deactivate; +} + +asmlinkage void __sched schedule(void) +{ +reschedule: + preempt_disable(); + + if(do_schedule() == SCHED_RESCHED) + goto reschedule; + + sched_preempt_enable_no_resched(); + if(unlikely(need_resched())) + goto reschedule; +} +EXPORT_SYMBOL(schedule); + +/** + * schedule_preempt_disabled - called with preemption disabled + * + * Returns with preemption disabled. Note: preempt_count must be 1 + */ +void __sched schedule_preempt_disabled(void) +{ + sched_preempt_enable_no_resched(); + schedule(); + preempt_disable(); +} + +#ifdef CONFIG_MUTEX_SPIN_ON_OWNER + +static inline bool owner_running(struct mutex *lock, struct task_struct *owner) +{ + if (lock->owner != owner) + return false; + + /* + * Ensure we emit the owner->on_cpu, dereference _after_ checking + * lock->owner still matches owner, if that fails, owner might + * point to free()d memory, if it still matches, the rcu_read_lock() + * ensures the memory stays valid. + */ + barrier(); + + return owner->on_cpu; +} + +/* + * Look out! "owner" is an entirely speculative pointer + * access and not reliable. + */ +int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner) +{ + rcu_read_lock(); + while (owner_running(lock, owner)) { + if (need_resched()) + break; + + arch_mutex_cpu_relax(); + } + rcu_read_unlock(); + + /* + * We break out the loop above on need_resched() and when the + * owner changed, which is a sign for heavy contention. Return + * success only when lock->owner is NULL. + */ + return lock->owner == NULL; +} +#endif + +#ifdef CONFIG_PREEMPT +/* + * this is the entry point to schedule() from in-kernel preemption + * off of preempt_enable. Kernel preemptions off return from interrupt + * occur there and call schedule directly. + */ +asmlinkage void __sched notrace preempt_schedule(void) +{ + struct thread_info *ti = current_thread_info(); + + /* + * If there is a non-zero preempt_count or interrupts are disabled, + * we do not want to preempt the current task. Just return.. + */ + if (likely(ti->preempt_count || irqs_disabled())) + return; + + do { + add_preempt_count_notrace(PREEMPT_ACTIVE); + schedule(); + sub_preempt_count_notrace(PREEMPT_ACTIVE); + + /* + * Check again in case we missed a preemption opportunity + * between schedule and now. + */ + barrier(); + } while (need_resched()); +} +EXPORT_SYMBOL(preempt_schedule); + +/* + * this is the entry point to schedule() from kernel preemption + * off of irq context. + * Note, that this is called and return with irqs disabled. This will + * protect us against recursive calling from irq. + */ +asmlinkage void __sched preempt_schedule_irq(void) +{ + struct thread_info *ti = current_thread_info(); + + /* Catch callers which need to be fixed */ + BUG_ON(ti->preempt_count || !irqs_disabled()); + + do { + add_preempt_count(PREEMPT_ACTIVE); + local_irq_enable(); + schedule(); + local_irq_disable(); + sub_preempt_count(PREEMPT_ACTIVE); + + /* + * Check again in case we missed a preemption opportunity + * between schedule and now. + */ + barrier(); + } while (need_resched()); +} + +#endif /* CONFIG_PREEMPT */ + +int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags, + void *key) +{ + return try_to_wake_up(curr->private, mode, wake_flags); +} +EXPORT_SYMBOL(default_wake_function); + +/* + * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just + * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve + * number) then we wake all the non-exclusive tasks and one exclusive task. + * + * There are circumstances in which we can try to wake a task which has already + * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns + * zero in this (rare) case, and we handle it by continuing to scan the queue. + */ +static void __wake_up_common(wait_queue_head_t *q, unsigned int mode, + int nr_exclusive, int wake_flags, void *key) +{ + struct list_head *tmp, *next; + + list_for_each_safe(tmp, next, &q->task_list) { + wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list); + unsigned int flags = curr->flags; + + if (curr->func(curr, mode, wake_flags, key) && + (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive) + break; + } +} + +/** + * __wake_up - wake up threads blocked on a waitqueue. + * @q: the waitqueue + * @mode: which threads + * @nr_exclusive: how many wake-one or wake-many threads to wake up + * @key: is directly passed to the wakeup function + * + * It may be assumed that this function implies a write memory barrier before + * changing the task state if and only if any tasks are woken up. + */ +void __wake_up(wait_queue_head_t *q, unsigned int mode, + int nr_exclusive, void *key) +{ + unsigned long flags; + + spin_lock_irqsave(&q->lock, flags); + __wake_up_common(q, mode, nr_exclusive, 0, key); + spin_unlock_irqrestore(&q->lock, flags); +} +EXPORT_SYMBOL(__wake_up); + +/* + * Same as __wake_up but called with the spinlock in wait_queue_head_t held. + */ +void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr) +{ + __wake_up_common(q, mode, nr, 0, NULL); +} +EXPORT_SYMBOL_GPL(__wake_up_locked); + +void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key) +{ + __wake_up_common(q, mode, 1, 0, key); +} +EXPORT_SYMBOL_GPL(__wake_up_locked_key); + +/** + * __wake_up_sync_key - wake up threads blocked on a waitqueue. + * @q: the waitqueue + * @mode: which threads + * @nr_exclusive: how many wake-one or wake-many threads to wake up + * @key: opaque value to be passed to wakeup targets + * + * The sync wakeup differs that the waker knows that it will schedule + * away soon, so while the target thread will be woken up, it will not + * be migrated to another CPU - ie. the two threads are 'synchronised' + * with each other. This can prevent needless bouncing between CPUs. + * + * On UP it can prevent extra preemption. + * + * It may be assumed that this function implies a write memory barrier before + * changing the task state if and only if any tasks are woken up. + */ +void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, + int nr_exclusive, void *key) +{ + unsigned long flags; + int wake_flags = WF_SYNC; + + if (unlikely(!q)) + return; + + if (unlikely(!nr_exclusive)) + wake_flags = 0; + + spin_lock_irqsave(&q->lock, flags); + __wake_up_common(q, mode, nr_exclusive, wake_flags, key); + spin_unlock_irqrestore(&q->lock, flags); +} +EXPORT_SYMBOL_GPL(__wake_up_sync_key); + +/** + * __wake_up_sync - wake up threads blocked on a waitqueue. + * @q: the waitqueue + * @mode: which threads + * @nr_exclusive: how many wake-one or wake-many threads to wake up + * + * The sync wakeup differs that the waker knows that it will schedule + * away soon, so while the target thread will be woken up, it will not + * be migrated to another CPU - ie. the two threads are 'synchronised' + * with each other. This can prevent needless bouncing between CPUs. + * + * On UP it can prevent extra preemption. + */ +void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive) +{ + unsigned long flags; + int sync = 1; + + if (unlikely(!q)) + return; + + if (unlikely(!nr_exclusive)) + sync = 0; + + spin_lock_irqsave(&q->lock, flags); + __wake_up_common(q, mode, nr_exclusive, sync, NULL); + spin_unlock_irqrestore(&q->lock, flags); +} +EXPORT_SYMBOL_GPL(__wake_up_sync); /* For internal use only */ + +/** + * complete: - signals a single thread waiting on this completion + * @x: holds the state of this particular completion + * + * This will wake up a single thread waiting on this completion. Threads will be + * awakened in the same order in which they were queued. + * + * See also complete_all(), wait_for_completion() and related routines. + * + * It may be assumed that this function implies a write memory barrier before + * changing the task state if and only if any tasks are woken up. + */ +void complete(struct completion *x) +{ + unsigned long flags; + + spin_lock_irqsave(&x->wait.lock, flags); + x->done++; + __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL); + spin_unlock_irqrestore(&x->wait.lock, flags); +} +EXPORT_SYMBOL(complete); + +/** + * complete_all: - signals all threads waiting on this completion + * @x: holds the state of this particular completion + * + * This will wake up all threads waiting on this particular completion event. + * + * It may be assumed that this function implies a write memory barrier before + * changing the task state if and only if any tasks are woken up. + */ +void complete_all(struct completion *x) +{ + unsigned long flags; + + spin_lock_irqsave(&x->wait.lock, flags); + x->done += UINT_MAX/2; + __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL); + spin_unlock_irqrestore(&x->wait.lock, flags); +} +EXPORT_SYMBOL(complete_all); + +static inline long __sched +do_wait_for_common(struct completion *x, long timeout, int state) +{ + if (!x->done) { + DECLARE_WAITQUEUE(wait, current); + + __add_wait_queue_tail_exclusive(&x->wait, &wait); + do { + if (signal_pending_state(state, current)) { + timeout = -ERESTARTSYS; + break; + } + __set_current_state(state); + spin_unlock_irq(&x->wait.lock); + timeout = schedule_timeout(timeout); + spin_lock_irq(&x->wait.lock); + } while (!x->done && timeout); + __remove_wait_queue(&x->wait, &wait); + if (!x->done) + return timeout; + } + x->done--; + return timeout ?: 1; +} + +static long __sched +wait_for_common(struct completion *x, long timeout, int state) +{ + might_sleep(); + + spin_lock_irq(&x->wait.lock); + timeout = do_wait_for_common(x, timeout, state); + spin_unlock_irq(&x->wait.lock); + return timeout; +} + +/** + * wait_for_completion: - waits for completion of a task + * @x: holds the state of this particular completion + * + * This waits to be signaled for completion of a specific task. It is NOT + * interruptible and there is no timeout. + * + * See also similar routines (i.e. wait_for_completion_timeout()) with timeout + * and interrupt capability. Also see complete(). + */ +void __sched wait_for_completion(struct completion *x) +{ + wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE); +} +EXPORT_SYMBOL(wait_for_completion); + +/** + * wait_for_completion_timeout: - waits for completion of a task (w/timeout) + * @x: holds the state of this particular completion + * @timeout: timeout value in jiffies + * + * This waits for either a completion of a specific task to be signaled or for a + * specified timeout to expire. The timeout is in jiffies. It is not + * interruptible. + * + * The return value is 0 if timed out, and positive (at least 1, or number of + * jiffies left till timeout) if completed. + */ +unsigned long __sched +wait_for_completion_timeout(struct completion *x, unsigned long timeout) +{ + return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE); +} +EXPORT_SYMBOL(wait_for_completion_timeout); + +/** + * wait_for_completion_interruptible: - waits for completion of a task (w/intr) + * @x: holds the state of this particular completion + * + * This waits for completion of a specific task to be signaled. It is + * interruptible. + * + * The return value is -ERESTARTSYS if interrupted, 0 if completed. + */ +int __sched wait_for_completion_interruptible(struct completion *x) +{ + long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE); + if (t == -ERESTARTSYS) + return t; + return 0; +} +EXPORT_SYMBOL(wait_for_completion_interruptible); + +/** + * wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr)) + * @x: holds the state of this particular completion + * @timeout: timeout value in jiffies + * + * This waits for either a completion of a specific task to be signaled or for a + * specified timeout to expire. It is interruptible. The timeout is in jiffies. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. + */ +long __sched +wait_for_completion_interruptible_timeout(struct completion *x, + unsigned long timeout) +{ + return wait_for_common(x, timeout, TASK_INTERRUPTIBLE); +} +EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); + +/** + * wait_for_completion_killable: - waits for completion of a task (killable) + * @x: holds the state of this particular completion + * + * This waits to be signaled for completion of a specific task. It can be + * interrupted by a kill signal. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. + */ +int __sched wait_for_completion_killable(struct completion *x) +{ + long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE); + if (t == -ERESTARTSYS) + return t; + return 0; +} +EXPORT_SYMBOL(wait_for_completion_killable); + +/** + * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable)) + * @x: holds the state of this particular completion + * @timeout: timeout value in jiffies + * + * This waits for either a completion of a specific task to be + * signaled or for a specified timeout to expire. It can be + * interrupted by a kill signal. The timeout is in jiffies. + */ +long __sched +wait_for_completion_killable_timeout(struct completion *x, + unsigned long timeout) +{ + return wait_for_common(x, timeout, TASK_KILLABLE); +} +EXPORT_SYMBOL(wait_for_completion_killable_timeout); + +/** + * try_wait_for_completion - try to decrement a completion without blocking + * @x: completion structure + * + * Returns: 0 if a decrement cannot be done without blocking + * 1 if a decrement succeeded. + * + * If a completion is being used as a counting completion, + * attempt to decrement the counter without blocking. This + * enables us to avoid waiting if the resource the completion + * is protecting is not available. + */ +bool try_wait_for_completion(struct completion *x) +{ + unsigned long flags; + int ret = 1; + + spin_lock_irqsave(&x->wait.lock, flags); + if (!x->done) + ret = 0; + else + x->done--; + spin_unlock_irqrestore(&x->wait.lock, flags); + return ret; +} +EXPORT_SYMBOL(try_wait_for_completion); + +/** + * completion_done - Test to see if a completion has any waiters + * @x: completion structure + * + * Returns: 0 if there are waiters (wait_for_completion() in progress) + * 1 if there are no waiters. + * + */ +bool completion_done(struct completion *x) +{ + unsigned long flags; + int ret = 1; + + spin_lock_irqsave(&x->wait.lock, flags); + if (!x->done) + ret = 0; + spin_unlock_irqrestore(&x->wait.lock, flags); + return ret; +} +EXPORT_SYMBOL(completion_done); + +static long __sched +sleep_on_common(wait_queue_head_t *q, int state, long timeout) +{ + unsigned long flags; + wait_queue_t wait; + + init_waitqueue_entry(&wait, current); + + __set_current_state(state); + + spin_lock_irqsave(&q->lock, flags); + __add_wait_queue(q, &wait); + spin_unlock(&q->lock); + timeout = schedule_timeout(timeout); + spin_lock_irq(&q->lock); + __remove_wait_queue(q, &wait); + spin_unlock_irqrestore(&q->lock, flags); + + return timeout; +} + +void __sched interruptible_sleep_on(wait_queue_head_t *q) +{ + sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); +} +EXPORT_SYMBOL(interruptible_sleep_on); + +long __sched +interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) +{ + return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout); +} +EXPORT_SYMBOL(interruptible_sleep_on_timeout); + +void __sched sleep_on(wait_queue_head_t *q) +{ + sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); +} +EXPORT_SYMBOL(sleep_on); + +long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) +{ + return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout); +} +EXPORT_SYMBOL(sleep_on_timeout); + +#ifdef CONFIG_RT_MUTEXES + +/* + * rt_mutex_setprio - set the current priority of a task + * @p: task + * @prio: prio value (kernel-internal form) + * + * This function changes the 'effective' priority of a task. It does + * not touch ->prio like __setscheduler(). + * + * Used by the rt_mutex code to implement priority inheritance logic. + */ +void rt_mutex_setprio(struct task_struct *p, int prio) +{ + unsigned long flags; + int queued, oldprio; + struct rq *rq; + + BUG_ON(prio < 0 || prio > MAX_PRIO); + + rq = task_grq_lock(p, &flags); + + trace_sched_pi_setprio(p, prio); + oldprio = p->prio; + queued = task_queued(p); + p->prio = prio; + if (task_running(p) && prio > oldprio) + resched_task(p); + if (queued) { + try_preempt(p, rq); + } + + task_grq_unlock(&flags); +} + +#endif + +void set_user_nice(struct task_struct *p, long nice) +{ + int queued, new_static, old_static; + unsigned long flags; + struct rq *rq; + + if (TASK_NICE(p) == nice || nice < -20 || nice > 19) + return; + new_static = NICE_TO_PRIO(nice); + /* + * We have to be careful, if called from sys_setpriority(), + * the task might be in the middle of scheduling on another CPU. + */ + rq = time_task_grq_lock(p, &flags); + /* + * The RT priorities are set via sched_setscheduler(), but we still + * allow the 'normal' nice value to be set - but as expected + * it wont have any effect on scheduling until the task is + * not SCHED_NORMAL/SCHED_BATCH: + */ + if (has_rt_policy(p)) { + p->static_prio = new_static; + goto out_unlock; + } + queued = task_queued(p); + + old_static = p->static_prio; + p->static_prio = new_static; + p->prio = p->static_prio; + + if (queued) { + if (new_static < old_static) + try_preempt(p, rq); + } else if (task_running(p)) { + reset_rq_task(rq, p); + if (old_static < new_static) + resched_task(p); + } +out_unlock: + task_grq_unlock(&flags); +} +EXPORT_SYMBOL(set_user_nice); + +/* + * can_nice - check if a task can reduce its nice value + * @p: task + * @nice: nice value + */ +int can_nice(const struct task_struct *p, const int nice) +{ + /* convert nice value [19,-20] to rlimit style value [1,40] */ + int nice_rlim = 20 - nice; + + return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) || + capable(CAP_SYS_NICE)); +} + +#ifdef __ARCH_WANT_SYS_NICE + +/* + * sys_nice - change the priority of the current process. + * @increment: priority increment + * + * sys_setpriority is a more generic, but much slower function that + * does similar things. + */ +SYSCALL_DEFINE1(nice, int, increment) +{ + long nice, retval; + + /* + * Setpriority might change our priority at the same moment. + * We don't have to worry. Conceptually one call occurs first + * and we have a single winner. + */ + if (increment < -40) + increment = -40; + if (increment > 40) + increment = 40; + + nice = TASK_NICE(current) + increment; + if (nice < -20) + nice = -20; + if (nice > 19) + nice = 19; + + if (increment < 0 && !can_nice(current, nice)) + return -EPERM; + + retval = security_task_setnice(current, nice); + if (retval) + return retval; + + set_user_nice(current, nice); + return 0; +} + +#endif + +/** + * task_prio - return the priority value of a given task. + * @p: the task in question. + * + * This is the priority value as seen by users in /proc. + * RT tasks are offset by -100. Normal tasks are centered around 1. + */ +int task_prio(const struct task_struct *p) +{ + return p->prio - NORMAL_PRIO; +} + +/** + * task_nice - return the nice value of a given task. + * @p: the task in question. + */ +int task_nice(const struct task_struct *p) +{ + return TASK_NICE(p); +} +EXPORT_SYMBOL_GPL(task_nice); + +/** + * idle_cpu - is a given cpu idle currently? + * @cpu: the processor in question. + */ +int idle_cpu(int cpu) +{ + return cpu_curr(cpu) == cpu_rq(cpu)->idle; +} + +/** + * idle_task - return the idle task for a given cpu. + * @cpu: the processor in question. + */ +struct task_struct *idle_task(int cpu) +{ + return cpu_rq(cpu)->idle; +} + +/** + * find_process_by_pid - find a process with a matching PID value. + * @pid: the pid in question. + */ +static inline struct task_struct *find_process_by_pid(pid_t pid) +{ + return pid ? find_task_by_vpid(pid) : current; +} + +/* Actually do priority change: must hold grq lock. */ +static void +__setscheduler(struct task_struct *p, struct rq *rq, int policy, int prio) +{ + int oldrtprio, oldprio; + + p->policy = policy; + oldrtprio = p->rt_priority; + p->rt_priority = prio; + oldprio = p->prio; + /* we are holding p->pi_lock already */ + p->prio = rt_mutex_getprio(p); + if (task_running(p)) { + reset_rq_task(rq, p); + /* Resched only if we might now be preempted */ + if (p->prio > oldprio || p->rt_priority > oldrtprio) + resched_task(p); + } +} + +/* + * check the target process has a UID that matches the current process's + */ +static bool check_same_owner(struct task_struct *p) +{ + const struct cred *cred = current_cred(), *pcred; + bool match; + + rcu_read_lock(); + pcred = __task_cred(p); + if (cred->user->user_ns == pcred->user->user_ns) + match = (cred->euid == pcred->euid || + cred->euid == pcred->uid); + else + match = false; + rcu_read_unlock(); + return match; +} + +static int __sched_setscheduler(struct task_struct *p, int policy, + const struct sched_param *param, bool user) +{ + struct sched_param zero_param = { .sched_priority = 0 }; + int queued, retval, oldpolicy = -1; + unsigned long flags, rlim_rtprio = 0; + int reset_on_fork; + struct rq *rq; + + /* may grab non-irq protected spin_locks */ + BUG_ON(in_interrupt()); + + if (is_rt_policy(policy) && !capable(CAP_SYS_NICE)) { + unsigned long lflags; + + if (!lock_task_sighand(p, &lflags)) + return -ESRCH; + rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO); + unlock_task_sighand(p, &lflags); + if (rlim_rtprio) + goto recheck; + param = &zero_param; + } +recheck: + /* double check policy once rq lock held */ + if (policy < 0) { + reset_on_fork = p->sched_reset_on_fork; + policy = oldpolicy = p->policy; + } else { + reset_on_fork = !!(policy & SCHED_RESET_ON_FORK); + policy &= ~SCHED_RESET_ON_FORK; + + if (!SCHED_RANGE(policy)) + return -EINVAL; + } + + /* + * Valid priorities for SCHED_FIFO and SCHED_RR are + * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL and + * SCHED_BATCH is 0. + */ + if (param->sched_priority < 0 || + (p->mm && param->sched_priority > MAX_USER_RT_PRIO - 1) || + (!p->mm && param->sched_priority > MAX_RT_PRIO - 1)) + return -EINVAL; + if (is_rt_policy(policy) != (param->sched_priority != 0)) + return -EINVAL; + + /* + * Allow unprivileged RT tasks to decrease priority: + */ + if (user && !capable(CAP_SYS_NICE)) { + if (is_rt_policy(policy)) { + unsigned long rlim_rtprio = + task_rlimit(p, RLIMIT_RTPRIO); + + /* can't set/change the rt policy */ + if (policy != p->policy && !rlim_rtprio) + return -EPERM; + + /* can't increase priority */ + if (param->sched_priority > p->rt_priority && + param->sched_priority > rlim_rtprio) + return -EPERM; + } else { + switch (p->policy) { + case SCHED_BATCH: + if (policy == SCHED_BATCH) + goto out; + if (policy != SCHED_IDLEPRIO) + return -EPERM; + break; + case SCHED_IDLEPRIO: + if (policy == SCHED_IDLEPRIO) + goto out; + return -EPERM; + default: + break; + } + } + + /* can't change other user's priorities */ + if (!check_same_owner(p)) + return -EPERM; + + /* Normal users shall not reset the sched_reset_on_fork flag */ + if (p->sched_reset_on_fork && !reset_on_fork) + return -EPERM; + } + + if (user) { + retval = security_task_setscheduler(p); + if (retval) + return retval; + } + + /* + * make sure no PI-waiters arrive (or leave) while we are + * changing the priority of the task: + */ + raw_spin_lock_irqsave(&p->pi_lock, flags); + /* + * To be able to change p->policy safely, the grunqueue lock must be + * held. + */ + rq = __task_grq_lock(p); + + /* + * Changing the policy of the stop threads its a very bad idea + */ + if (p == rq->stop) { + __task_grq_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + return -EINVAL; + } + + /* + * If not changing anything there's no need to proceed further: + */ + if (unlikely(policy == p->policy && (!is_rt_policy(policy) || + param->sched_priority == p->rt_priority))) { + + __task_grq_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + return 0; + } + + /* recheck policy now with rq lock held */ + if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { + policy = oldpolicy = -1; + __task_grq_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + goto recheck; + } + p->sched_reset_on_fork = reset_on_fork; + + queued = task_queued(p); + __setscheduler(p, rq, policy, param->sched_priority); + if (queued) { + try_preempt(p, rq); + } + __task_grq_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + + rt_mutex_adjust_pi(p); +out: + return 0; +} + +/** + * sched_setscheduler - change the scheduling policy and/or RT priority of a thread. + * @p: the task in question. + * @policy: new policy. + * @param: structure containing the new RT priority. + * + * NOTE that the task may be already dead. + */ +int sched_setscheduler(struct task_struct *p, int policy, + const struct sched_param *param) +{ + return __sched_setscheduler(p, policy, param, true); +} + +EXPORT_SYMBOL_GPL(sched_setscheduler); + +/** + * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace. + * @p: the task in question. + * @policy: new policy. + * @param: structure containing the new RT priority. + * + * Just like sched_setscheduler, only don't bother checking if the + * current context has permission. For example, this is needed in + * stop_machine(): we create temporary high priority worker threads, + * but our caller might not have that capability. + */ +int sched_setscheduler_nocheck(struct task_struct *p, int policy, + const struct sched_param *param) +{ + return __sched_setscheduler(p, policy, param, false); +} + +static int +do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) +{ + struct sched_param lparam; + struct task_struct *p; + int retval; + + if (!param || pid < 0) + return -EINVAL; + if (copy_from_user(&lparam, param, sizeof(struct sched_param))) + return -EFAULT; + + rcu_read_lock(); + retval = -ESRCH; + p = find_process_by_pid(pid); + if (p != NULL) + retval = sched_setscheduler(p, policy, &lparam); + rcu_read_unlock(); + + return retval; +} + +/** + * sys_sched_setscheduler - set/change the scheduler policy and RT priority + * @pid: the pid in question. + * @policy: new policy. + * @param: structure containing the new RT priority. + */ +asmlinkage long sys_sched_setscheduler(pid_t pid, int policy, + struct sched_param __user *param) +{ + /* negative values for policy are not valid */ + if (policy < 0) + return -EINVAL; + + return do_sched_setscheduler(pid, policy, param); +} + +/** + * sys_sched_setparam - set/change the RT priority of a thread + * @pid: the pid in question. + * @param: structure containing the new RT priority. + */ +SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) +{ + return do_sched_setscheduler(pid, -1, param); +} + +/** + * sys_sched_getscheduler - get the policy (scheduling class) of a thread + * @pid: the pid in question. + */ +SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid) +{ + struct task_struct *p; + int retval = -EINVAL; + + if (pid < 0) + goto out_nounlock; + + retval = -ESRCH; + rcu_read_lock(); + p = find_process_by_pid(pid); + if (p) { + retval = security_task_getscheduler(p); + if (!retval) + retval = p->policy; + } + rcu_read_unlock(); + +out_nounlock: + return retval; +} + +/** + * sys_sched_getscheduler - get the RT priority of a thread + * @pid: the pid in question. + * @param: structure containing the RT priority. + */ +SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) +{ + struct sched_param lp; + struct task_struct *p; + int retval = -EINVAL; + + if (!param || pid < 0) + goto out_nounlock; + + rcu_read_lock(); + p = find_process_by_pid(pid); + retval = -ESRCH; + if (!p) + goto out_unlock; + + retval = security_task_getscheduler(p); + if (retval) + goto out_unlock; + + lp.sched_priority = p->rt_priority; + rcu_read_unlock(); + + /* + * This one might sleep, we cannot do it with a spinlock held ... + */ + retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; + +out_nounlock: + return retval; + +out_unlock: + rcu_read_unlock(); + return retval; +} + +long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) +{ + cpumask_var_t cpus_allowed, new_mask; + struct task_struct *p; + int retval; + + get_online_cpus(); + rcu_read_lock(); + + p = find_process_by_pid(pid); + if (!p) { + rcu_read_unlock(); + put_online_cpus(); + return -ESRCH; + } + + /* Prevent p going away */ + get_task_struct(p); + rcu_read_unlock(); + + if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) { + retval = -ENOMEM; + goto out_put_task; + } + if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) { + retval = -ENOMEM; + goto out_free_cpus_allowed; + } + retval = -EPERM; + if (!check_same_owner(p) && !ns_capable(task_user_ns(p), CAP_SYS_NICE)) + goto out_unlock; + + retval = security_task_setscheduler(p); + if (retval) + goto out_unlock; + + cpuset_cpus_allowed(p, cpus_allowed); + cpumask_and(new_mask, in_mask, cpus_allowed); +again: + retval = set_cpus_allowed_ptr(p, new_mask); + + if (!retval) { + cpuset_cpus_allowed(p, cpus_allowed); + if (!cpumask_subset(new_mask, cpus_allowed)) { + /* + * We must have raced with a concurrent cpuset + * update. Just reset the cpus_allowed to the + * cpuset's cpus_allowed + */ + cpumask_copy(new_mask, cpus_allowed); + goto again; + } + } +out_unlock: + free_cpumask_var(new_mask); +out_free_cpus_allowed: + free_cpumask_var(cpus_allowed); +out_put_task: + put_task_struct(p); + put_online_cpus(); + return retval; +} + +static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len, + cpumask_t *new_mask) +{ + if (len < sizeof(cpumask_t)) { + memset(new_mask, 0, sizeof(cpumask_t)); + } else if (len > sizeof(cpumask_t)) { + len = sizeof(cpumask_t); + } + return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0; +} + + +/** + * sys_sched_setaffinity - set the cpu affinity of a process + * @pid: pid of the process + * @len: length in bytes of the bitmask pointed to by user_mask_ptr + * @user_mask_ptr: user-space pointer to the new cpu mask + */ +SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len, + unsigned long __user *, user_mask_ptr) +{ + cpumask_var_t new_mask; + int retval; + + if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) + return -ENOMEM; + + retval = get_user_cpu_mask(user_mask_ptr, len, new_mask); + if (retval == 0) + retval = sched_setaffinity(pid, new_mask); + free_cpumask_var(new_mask); + return retval; +} + +long sched_getaffinity(pid_t pid, cpumask_t *mask) +{ + struct task_struct *p; + unsigned long flags; + int retval; + + get_online_cpus(); + rcu_read_lock(); + + retval = -ESRCH; + p = find_process_by_pid(pid); + if (!p) + goto out_unlock; + + retval = security_task_getscheduler(p); + if (retval) + goto out_unlock; + + grq_lock_irqsave(&flags); + cpumask_and(mask, tsk_cpus_allowed(p), cpu_online_mask); + grq_unlock_irqrestore(&flags); + +out_unlock: + rcu_read_unlock(); + put_online_cpus(); + + return retval; +} + +/** + * sys_sched_getaffinity - get the cpu affinity of a process + * @pid: pid of the process + * @len: length in bytes of the bitmask pointed to by user_mask_ptr + * @user_mask_ptr: user-space pointer to hold the current cpu mask + */ +SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len, + unsigned long __user *, user_mask_ptr) +{ + int ret; + cpumask_var_t mask; + + if ((len * BITS_PER_BYTE) < nr_cpu_ids) + return -EINVAL; + if (len & (sizeof(unsigned long)-1)) + return -EINVAL; + + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) + return -ENOMEM; + + ret = sched_getaffinity(pid, mask); + if (ret == 0) { + size_t retlen = min_t(size_t, len, cpumask_size()); + + if (copy_to_user(user_mask_ptr, mask, retlen)) + ret = -EFAULT; + else + ret = retlen; + } + free_cpumask_var(mask); + + return ret; +} + +/** + * sys_sched_yield - yield the current processor to other threads. + * + * This function yields the current CPU to other tasks. It does this by + * scheduling away the current task. + */ +SYSCALL_DEFINE0(sched_yield) +{ + struct task_struct *p; + + p = current; + grq_lock_irq(); + requeue_task(p); + + /* + * Since we are going to call schedule() anyway, there's + * no need to preempt or enable interrupts: + */ + __release(grq.lock); + spin_release(&grq.lock.dep_map, 1, _THIS_IP_); + do_raw_spin_unlock(&grq.lock); + sched_preempt_enable_no_resched(); + + schedule(); + + return 0; +} + +static inline bool should_resched(void) +{ + return need_resched() && !(preempt_count() & PREEMPT_ACTIVE); +} + +static void __cond_resched(void) +{ + /* NOT a real fix but will make voluntary preempt work. 馬鹿な事 */ + if (unlikely(system_state != SYSTEM_RUNNING)) + return; + + add_preempt_count(PREEMPT_ACTIVE); + schedule(); + sub_preempt_count(PREEMPT_ACTIVE); +} + +int __sched _cond_resched(void) +{ + if (should_resched()) { + __cond_resched(); + return 1; + } + return 0; +} +EXPORT_SYMBOL(_cond_resched); + +/* + * __cond_resched_lock() - if a reschedule is pending, drop the given lock, + * call schedule, and on return reacquire the lock. + * + * This works OK both with and without CONFIG_PREEMPT. We do strange low-level + * operations here to prevent schedule() from being called twice (once via + * spin_unlock(), once by hand). + */ +int __cond_resched_lock(spinlock_t *lock) +{ + int resched = should_resched(); + int ret = 0; + + lockdep_assert_held(lock); + + if (spin_needbreak(lock) || resched) { + spin_unlock(lock); + if (resched) + __cond_resched(); + else + cpu_relax(); + ret = 1; + spin_lock(lock); + } + return ret; +} +EXPORT_SYMBOL(__cond_resched_lock); + +int __sched __cond_resched_softirq(void) +{ + BUG_ON(!in_softirq()); + + if (should_resched()) { + local_bh_enable(); + __cond_resched(); + local_bh_disable(); + return 1; + } + return 0; +} +EXPORT_SYMBOL(__cond_resched_softirq); + +/** + * yield - yield the current processor to other threads. + * + * This is a shortcut for kernel-space yielding - it marks the + * thread runnable and calls sys_sched_yield(). + */ +void __sched yield(void) +{ + set_current_state(TASK_RUNNING); + sys_sched_yield(); +} +EXPORT_SYMBOL(yield); + +/** + * yield_to - yield the current processor to another thread in + * your thread group, or accelerate that thread toward the + * processor it's on. + * @p: target task + * @preempt: whether task preemption is allowed or not + * + * It's the caller's job to ensure that the target task struct + * can't go away on us before we can do any checks. + * + * Returns true if we indeed boosted the target task. + */ +bool __sched yield_to(struct task_struct *p, bool preempt) +{ + unsigned long flags; + bool yielded = 0; + struct rq *rq; + struct task_struct *curr; + + rq = this_rq(); + grq_lock_irqsave(&flags); + if (task_running(p) || p->state) + goto out_unlock; + yielded = 1; + curr = rq->curr; + p->time_slice += curr->time_slice; + curr->time_slice = 0; + if (p->time_slice > timeslice()) + p->time_slice = timeslice(); + set_tsk_need_resched(curr); +out_unlock: + grq_unlock_irqrestore(&flags); + + if (yielded) + schedule(); + return yielded; +} +EXPORT_SYMBOL_GPL(yield_to); + +/* + * This task is about to go to sleep on IO. Increment rq->nr_iowait so + * that process accounting knows that this is a task in IO wait state. + * + * But don't do that if it is a deliberate, throttling IO wait (this task + * has set its backing_dev_info: the queue against which it should throttle) + */ +void __sched io_schedule(void) +{ + struct rq *rq = raw_rq(); + + delayacct_blkio_start(); + atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); + current->in_iowait = 1; + schedule(); + current->in_iowait = 0; + atomic_dec(&rq->nr_iowait); + delayacct_blkio_end(); +} +EXPORT_SYMBOL(io_schedule); + +long __sched io_schedule_timeout(long timeout) +{ + struct rq *rq = raw_rq(); + long ret; + + delayacct_blkio_start(); + atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); + current->in_iowait = 1; + ret = schedule_timeout(timeout); + current->in_iowait = 0; + atomic_dec(&rq->nr_iowait); + delayacct_blkio_end(); + return ret; +} + +/** + * sys_sched_get_priority_max - return maximum RT priority. + * @policy: scheduling class. + * + * this syscall returns the maximum rt_priority that can be used + * by a given scheduling class. + */ +SYSCALL_DEFINE1(sched_get_priority_max, int, policy) +{ + int ret = -EINVAL; + + switch (policy) { + case SCHED_FIFO: + case SCHED_RR: + ret = MAX_USER_RT_PRIO-1; + break; + case SCHED_NORMAL: + case SCHED_BATCH: + case SCHED_IDLEPRIO: + ret = 0; + break; + } + return ret; +} + +/** + * sys_sched_get_priority_min - return minimum RT priority. + * @policy: scheduling class. + * + * this syscall returns the minimum rt_priority that can be used + * by a given scheduling class. + */ +SYSCALL_DEFINE1(sched_get_priority_min, int, policy) +{ + int ret = -EINVAL; + + switch (policy) { + case SCHED_FIFO: + case SCHED_RR: + ret = 1; + break; + case SCHED_NORMAL: + case SCHED_BATCH: + case SCHED_IDLEPRIO: + ret = 0; + break; + } + return ret; +} + +/** + * sys_sched_rr_get_interval - return the default timeslice of a process. + * @pid: pid of the process. + * @interval: userspace pointer to the timeslice value. + * + * this syscall writes the default timeslice value of a given process + * into the user-space timespec buffer. A value of '0' means infinity. + */ +SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, + struct timespec __user *, interval) +{ + struct task_struct *p; + unsigned int time_slice; + unsigned long flags; + int retval; + struct timespec t; + + if (pid < 0) + return -EINVAL; + + retval = -ESRCH; + rcu_read_lock(); + p = find_process_by_pid(pid); + if (!p) + goto out_unlock; + + retval = security_task_getscheduler(p); + if (retval) + goto out_unlock; + + grq_lock_irqsave(&flags); + time_slice = p->policy == SCHED_FIFO ? 0 : MS_TO_NS(rr_interval); + grq_unlock_irqrestore(&flags); + + rcu_read_unlock(); + t = ns_to_timespec(time_slice); + retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0; + return retval; + +out_unlock: + rcu_read_unlock(); + return retval; +} + +static const char stat_nam[] = TASK_STATE_TO_CHAR_STR; + +void sched_show_task(struct task_struct *p) +{ + unsigned long free = 0; + unsigned state; + + state = p->state ? __ffs(p->state) + 1 : 0; + printk(KERN_INFO "%-15.15s %c", p->comm, + state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); +#if BITS_PER_LONG == 32 + if (state == TASK_RUNNING) + printk(KERN_CONT " running "); + else + printk(KERN_CONT " %08lx ", thread_saved_pc(p)); +#else + if (state == TASK_RUNNING) + printk(KERN_CONT " running task "); + else + printk(KERN_CONT " %016lx ", thread_saved_pc(p)); +#endif +#ifdef CONFIG_DEBUG_STACK_USAGE + free = stack_not_used(p); +#endif + printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free, + task_pid_nr(p), task_pid_nr(p->real_parent), + (unsigned long)task_thread_info(p)->flags); + + show_stack(p, NULL); +} + +void show_state_filter(unsigned long state_filter) +{ + struct task_struct *g, *p; + +#if BITS_PER_LONG == 32 + printk(KERN_INFO + " task PC stack pid father\n"); +#else + printk(KERN_INFO + " task PC stack pid father\n"); +#endif + rcu_read_lock(); + do_each_thread(g, p) { + /* + * reset the NMI-timeout, listing all files on a slow + * console might take a lot of time: + */ + touch_nmi_watchdog(); + if (!state_filter || (p->state & state_filter)) + sched_show_task(p); + } while_each_thread(g, p); + + touch_all_softlockup_watchdogs(); + + rcu_read_unlock(); + /* + * Only show locks if all tasks are dumped: + */ + if (!state_filter) + debug_show_all_locks(); +} + +#ifdef CONFIG_SMP +void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) +{ + cpumask_copy(tsk_cpus_allowed(p), new_mask); +} +#endif + +/** + * init_idle - set up an idle thread for a given CPU + * @idle: task in question + * @cpu: cpu the idle task belongs to + * + * NOTE: this function does not set the idle thread's NEED_RESCHED + * flag, to make booting more robust. + */ +void init_idle(struct task_struct *idle, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + time_grq_lock(rq, &flags); + idle->last_ran = rq->clock; + idle->state = TASK_RUNNING; + /* Setting prio to illegal value shouldn't matter when never queued */ + idle->prio = PRIO_LIMIT; + idle->policy = SCHED_IDLE; + set_rq_task(rq, idle); + do_set_cpus_allowed(idle, &cpumask_of_cpu(cpu)); + /* Silence PROVE_RCU */ + rcu_read_lock(); + set_task_cpu(idle, cpu); + rcu_read_unlock(); + rq->curr = rq->idle = idle; + idle->on_cpu = 1; + grq_unlock_irqrestore(&flags); + + /* Set the preempt count _outside_ the spinlocks! */ + task_thread_info(idle)->preempt_count = 0; + + ftrace_graph_init_idle_task(idle, cpu); +#if defined(CONFIG_SMP) + sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); +#endif +} + +#ifdef CONFIG_SMP +#ifdef CONFIG_NO_HZ +void select_nohz_load_balancer(int stop_tick) +{ +} + +void set_cpu_sd_state_idle(void) {} +#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) +/** + * lowest_flag_domain - Return lowest sched_domain containing flag. + * @cpu: The cpu whose lowest level of sched domain is to + * be returned. + * @flag: The flag to check for the lowest sched_domain + * for the given cpu. + * + * Returns the lowest sched_domain of a cpu which contains the given flag. + */ +static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) +{ + struct sched_domain *sd; + + for_each_domain(cpu, sd) + if (sd && (sd->flags & flag)) + break; + + return sd; +} + +/** + * for_each_flag_domain - Iterates over sched_domains containing the flag. + * @cpu: The cpu whose domains we're iterating over. + * @sd: variable holding the value of the power_savings_sd + * for cpu. + * @flag: The flag to filter the sched_domains to be iterated. + * + * Iterates over all the scheduler domains for a given cpu that has the 'flag' + * set, starting from the lowest sched_domain to the highest. + */ +#define for_each_flag_domain(cpu, sd, flag) \ + for (sd = lowest_flag_domain(cpu, flag); \ + (sd && (sd->flags & flag)); sd = sd->parent) + +#endif /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */ + +static inline void resched_cpu(int cpu) +{ + unsigned long flags; + + grq_lock_irqsave(&flags); + resched_task(cpu_curr(cpu)); + grq_unlock_irqrestore(&flags); +} + +/* + * In the semi idle case, use the nearest busy cpu for migrating timers + * from an idle cpu. This is good for power-savings. + * + * We don't do similar optimization for completely idle system, as + * selecting an idle cpu will add more delays to the timers than intended + * (as that cpu's timer base may not be uptodate wrt jiffies etc). + */ +int get_nohz_timer_target(void) +{ + int cpu = smp_processor_id(); + int i; + struct sched_domain *sd; + + rcu_read_lock(); + for_each_domain(cpu, sd) { + for_each_cpu(i, sched_domain_span(sd)) { + if (!idle_cpu(i)) + cpu = i; + goto unlock; + } + } +unlock: + rcu_read_unlock(); + return cpu; +} + +/* + * When add_timer_on() enqueues a timer into the timer wheel of an + * idle CPU then this timer might expire before the next timer event + * which is scheduled to wake up that CPU. In case of a completely + * idle system the next event might even be infinite time into the + * future. wake_up_idle_cpu() ensures that the CPU is woken up and + * leaves the inner idle loop so the newly added timer is taken into + * account when the CPU goes back to idle and evaluates the timer + * wheel for the next timer event. + */ +void wake_up_idle_cpu(int cpu) +{ + struct task_struct *idle; + struct rq *rq; + + if (cpu == smp_processor_id()) + return; + + rq = cpu_rq(cpu); + idle = rq->idle; + + /* + * This is safe, as this function is called with the timer + * wheel base lock of (cpu) held. When the CPU is on the way + * to idle and has not yet set rq->curr to idle then it will + * be serialised on the timer wheel base lock and take the new + * timer into account automatically. + */ + if (unlikely(rq->curr != idle)) + return; + + /* + * We can set TIF_RESCHED on the idle task of the other CPU + * lockless. The worst case is that the other CPU runs the + * idle task through an additional NOOP schedule() + */ + set_tsk_need_resched(idle); + + /* NEED_RESCHED must be visible before we test polling */ + smp_mb(); + if (!tsk_is_polling(idle)) + smp_send_reschedule(cpu); +} + +#endif /* CONFIG_NO_HZ */ + +/* + * Change a given task's CPU affinity. Migrate the thread to a + * proper CPU and schedule it away if the CPU it's executing on + * is removed from the allowed bitmask. + * + * NOTE: the caller must have a valid reference to the task, the + * task must not exit() & deallocate itself prematurely. The + * call is not atomic; no spinlocks may be held. + */ +int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) +{ + bool running_wrong = false; + bool queued = false; + unsigned long flags; + struct rq *rq; + int ret = 0; + + rq = task_grq_lock(p, &flags); + + if (cpumask_equal(tsk_cpus_allowed(p), new_mask)) + goto out; + + if (!cpumask_intersects(new_mask, cpu_active_mask)) { + ret = -EINVAL; + goto out; + } + + if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) { + ret = -EINVAL; + goto out; + } + + queued = task_queued(p); + + do_set_cpus_allowed(p, new_mask); + + /* Can the task run on the task's current CPU? If so, we're done */ + if (cpumask_test_cpu(task_cpu(p), new_mask)) + goto out; + + if (task_running(p)) { + /* Task is running on the wrong cpu now, reschedule it. */ + if (rq == this_rq()) { + set_tsk_need_resched(p); + running_wrong = true; + } else + resched_task(p); + } else + set_task_cpu(p, cpumask_any_and(cpu_active_mask, new_mask)); + +out: + if (queued) + try_preempt(p, rq); + task_grq_unlock(&flags); + + if (running_wrong) + _cond_resched(); + + return ret; +} +EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr); + +#ifdef CONFIG_HOTPLUG_CPU +/* Run through task list and find tasks affined to just the dead cpu, then + * allocate a new affinity */ +static void break_sole_affinity(int src_cpu, struct task_struct *idle) +{ + struct task_struct *p, *t; + + do_each_thread(t, p) { + if (p != idle && !online_cpus(p)) { + cpumask_copy(tsk_cpus_allowed(p), cpu_possible_mask); + /* + * Don't tell them about moving exiting tasks or + * kernel threads (both mm NULL), since they never + * leave kernel. + */ + if (p->mm && printk_ratelimit()) { + printk(KERN_INFO "process %d (%s) no " + "longer affine to cpu %d\n", + task_pid_nr(p), p->comm, src_cpu); + } + } + clear_sticky(p); + } while_each_thread(t, p); +} + +/* + * Schedules idle task to be the next runnable task on current CPU. + * It does so by boosting its priority to highest possible. + * Used by CPU offline code. + */ +void sched_idle_next(struct rq *rq, int this_cpu, struct task_struct *idle) +{ + /* cpu has to be offline */ + BUG_ON(cpu_online(this_cpu)); + + __setscheduler(idle, rq, SCHED_FIFO, STOP_PRIO); + + activate_idle_task(idle); + set_tsk_need_resched(rq->curr); +} + +/* + * Ensures that the idle task is using init_mm right before its cpu goes + * offline. + */ +void idle_task_exit(void) +{ + struct mm_struct *mm = current->active_mm; + + BUG_ON(cpu_online(smp_processor_id())); + + if (mm != &init_mm) + switch_mm(mm, &init_mm, current); + mmdrop(mm); +} +#endif /* CONFIG_HOTPLUG_CPU */ +void sched_set_stop_task(int cpu, struct task_struct *stop) +{ + struct sched_param stop_param = { .sched_priority = STOP_PRIO }; + struct sched_param start_param = { .sched_priority = MAX_USER_RT_PRIO - 1 }; + struct task_struct *old_stop = cpu_rq(cpu)->stop; + + if (stop) { + /* + * Make it appear like a SCHED_FIFO task, its something + * userspace knows about and won't get confused about. + * + * Also, it will make PI more or less work without too + * much confusion -- but then, stop work should not + * rely on PI working anyway. + */ + sched_setscheduler_nocheck(stop, SCHED_FIFO, &stop_param); + } + + cpu_rq(cpu)->stop = stop; + + if (old_stop) { + /* + * Reset it back to a normal rt scheduling prio so that + * it can die in pieces. + */ + sched_setscheduler_nocheck(old_stop, SCHED_FIFO, &start_param); + } +} + + +#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) + +static struct ctl_table sd_ctl_dir[] = { + { + .procname = "sched_domain", + .mode = 0555, + }, + {} +}; + +static struct ctl_table sd_ctl_root[] = { + { + .procname = "kernel", + .mode = 0555, + .child = sd_ctl_dir, + }, + {} +}; + +static struct ctl_table *sd_alloc_ctl_entry(int n) +{ + struct ctl_table *entry = + kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL); + + return entry; +} + +static void sd_free_ctl_entry(struct ctl_table **tablep) +{ + struct ctl_table *entry; + + /* + * In the intermediate directories, both the child directory and + * procname are dynamically allocated and could fail but the mode + * will always be set. In the lowest directory the names are + * static strings and all have proc handlers. + */ + for (entry = *tablep; entry->mode; entry++) { + if (entry->child) + sd_free_ctl_entry(&entry->child); + if (entry->proc_handler == NULL) + kfree(entry->procname); + } + + kfree(*tablep); + *tablep = NULL; +} + +static void +set_table_entry(struct ctl_table *entry, + const char *procname, void *data, int maxlen, + mode_t mode, proc_handler *proc_handler) +{ + entry->procname = procname; + entry->data = data; + entry->maxlen = maxlen; + entry->mode = mode; + entry->proc_handler = proc_handler; +} + +static struct ctl_table * +sd_alloc_ctl_domain_table(struct sched_domain *sd) +{ + struct ctl_table *table = sd_alloc_ctl_entry(13); + + if (table == NULL) + return NULL; + + set_table_entry(&table[0], "min_interval", &sd->min_interval, + sizeof(long), 0644, proc_doulongvec_minmax); + set_table_entry(&table[1], "max_interval", &sd->max_interval, + sizeof(long), 0644, proc_doulongvec_minmax); + set_table_entry(&table[2], "busy_idx", &sd->busy_idx, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[3], "idle_idx", &sd->idle_idx, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[5], "wake_idx", &sd->wake_idx, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[7], "busy_factor", &sd->busy_factor, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[9], "cache_nice_tries", + &sd->cache_nice_tries, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[10], "flags", &sd->flags, + sizeof(int), 0644, proc_dointvec_minmax); + set_table_entry(&table[11], "name", sd->name, + CORENAME_MAX_SIZE, 0444, proc_dostring); + /* &table[12] is terminator */ + + return table; +} + +static ctl_table *sd_alloc_ctl_cpu_table(int cpu) +{ + struct ctl_table *entry, *table; + struct sched_domain *sd; + int domain_num = 0, i; + char buf[32]; + + for_each_domain(cpu, sd) + domain_num++; + entry = table = sd_alloc_ctl_entry(domain_num + 1); + if (table == NULL) + return NULL; + + i = 0; + for_each_domain(cpu, sd) { + snprintf(buf, 32, "domain%d", i); + entry->procname = kstrdup(buf, GFP_KERNEL); + entry->mode = 0555; + entry->child = sd_alloc_ctl_domain_table(sd); + entry++; + i++; + } + return table; +} + +static struct ctl_table_header *sd_sysctl_header; +static void register_sched_domain_sysctl(void) +{ + int i, cpu_num = num_possible_cpus(); + struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1); + char buf[32]; + + WARN_ON(sd_ctl_dir[0].child); + sd_ctl_dir[0].child = entry; + + if (entry == NULL) + return; + + for_each_possible_cpu(i) { + snprintf(buf, 32, "cpu%d", i); + entry->procname = kstrdup(buf, GFP_KERNEL); + entry->mode = 0555; + entry->child = sd_alloc_ctl_cpu_table(i); + entry++; + } + + WARN_ON(sd_sysctl_header); + sd_sysctl_header = register_sysctl_table(sd_ctl_root); +} + +/* may be called multiple times per register */ +static void unregister_sched_domain_sysctl(void) +{ + if (sd_sysctl_header) + unregister_sysctl_table(sd_sysctl_header); + sd_sysctl_header = NULL; + if (sd_ctl_dir[0].child) + sd_free_ctl_entry(&sd_ctl_dir[0].child); +} +#else +static void register_sched_domain_sysctl(void) +{ +} +static void unregister_sched_domain_sysctl(void) +{ +} +#endif + +static void set_rq_online(struct rq *rq) +{ + if (!rq->online) { + cpumask_set_cpu(cpu_of(rq), rq->rd->online); + rq->online = true; + } +} + +static void set_rq_offline(struct rq *rq) +{ + if (rq->online) { + cpumask_clear_cpu(cpu_of(rq), rq->rd->online); + rq->online = false; + } +} + +/* + * migration_call - callback that gets triggered when a CPU is added. + */ +static int __cpuinit +migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) +{ + int cpu = (long)hcpu; + unsigned long flags; + struct rq *rq = cpu_rq(cpu); +#ifdef CONFIG_HOTPLUG_CPU + struct task_struct *idle = rq->idle; +#endif + + switch (action & ~CPU_TASKS_FROZEN) { + + case CPU_UP_PREPARE: + break; + + case CPU_ONLINE: + /* Update our root-domain */ + grq_lock_irqsave(&flags); + if (rq->rd) { + BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); + + set_rq_online(rq); + } + grq.noc = num_online_cpus(); + grq_unlock_irqrestore(&flags); + break; + +#ifdef CONFIG_HOTPLUG_CPU + case CPU_DEAD: + /* Idle task back to normal (off runqueue, low prio) */ + grq_lock_irq(); + put_prev_task(rq, idle, true, false); + idle->static_prio = MAX_PRIO; + __setscheduler(idle, rq, SCHED_NORMAL, 0); + idle->prio = PRIO_LIMIT; + set_rq_task(rq, idle); + grq_unlock_irq(); + break; + + case CPU_DYING: + /* Update our root-domain */ + grq_lock_irqsave(&flags); + sched_idle_next(rq, cpu, idle); + if (rq->rd) { + BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); + set_rq_offline(rq); + } + break_sole_affinity(cpu, idle); + grq.noc = num_online_cpus(); + grq_unlock_irqrestore(&flags); + break; +#endif + } + return NOTIFY_OK; +} + +/* + * Register at high priority so that task migration (migrate_all_tasks) + * happens before everything else. This has to be lower priority than + * the notifier in the perf_counter subsystem, though. + */ +static struct notifier_block __cpuinitdata migration_notifier = { + .notifier_call = migration_call, + .priority = CPU_PRI_MIGRATION, +}; + +static int __cpuinit sched_cpu_active(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_ONLINE: + case CPU_DOWN_FAILED: + set_cpu_active((long)hcpu, true); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_DOWN_PREPARE: + set_cpu_active((long)hcpu, false); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +int __init migration_init(void) +{ + void *cpu = (void *)(long)smp_processor_id(); + int err; + + /* Initialise migration for the boot CPU */ + err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu); + BUG_ON(err == NOTIFY_BAD); + migration_call(&migration_notifier, CPU_ONLINE, cpu); + register_cpu_notifier(&migration_notifier); + + /* Register cpu active notifiers */ + cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE); + cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE); + + return 0; +} +early_initcall(migration_init); +#endif + +#ifdef CONFIG_SMP + +static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ + +#ifdef CONFIG_SCHED_DEBUG + +static __read_mostly int sched_domain_debug_enabled; + +static int __init sched_domain_debug_setup(char *str) +{ + sched_domain_debug_enabled = 1; + + return 0; +} +early_param("sched_debug", sched_domain_debug_setup); + +static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, + struct cpumask *groupmask) +{ + struct sched_group *group = sd->groups; + char str[256]; + + cpulist_scnprintf(str, sizeof(str), sched_domain_span(sd)); + cpumask_clear(groupmask); + + printk(KERN_DEBUG "%*s domain %d: ", level, "", level); + + if (!(sd->flags & SD_LOAD_BALANCE)) { + printk("does not load-balance\n"); + if (sd->parent) + printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain" + " has parent"); + return -1; + } + + printk(KERN_CONT "span %s level %s\n", str, sd->name); + + if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { + printk(KERN_ERR "ERROR: domain->span does not contain " + "CPU%d\n", cpu); + } + if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) { + printk(KERN_ERR "ERROR: domain->groups does not contain" + " CPU%d\n", cpu); + } + + printk(KERN_DEBUG "%*s groups:", level + 1, ""); + do { + if (!group) { + printk("\n"); + printk(KERN_ERR "ERROR: group is NULL\n"); + break; + } + + if (!group->sgp->power) { + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: domain->cpu_power not " + "set\n"); + break; + } + + if (!cpumask_weight(sched_group_cpus(group))) { + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: empty group\n"); + break; + } + + if (cpumask_intersects(groupmask, sched_group_cpus(group))) { + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: repeated CPUs\n"); + break; + } + + cpumask_or(groupmask, groupmask, sched_group_cpus(group)); + + cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group)); + + printk(KERN_CONT " %s", str); + if (group->sgp->power != SCHED_POWER_SCALE) { + printk(KERN_CONT " (cpu_power = %d)", + group->sgp->power); + } + + group = group->next; + } while (group != sd->groups); + printk(KERN_CONT "\n"); + + if (!cpumask_equal(sched_domain_span(sd), groupmask)) + printk(KERN_ERR "ERROR: groups don't span domain->span\n"); + + if (sd->parent && + !cpumask_subset(groupmask, sched_domain_span(sd->parent))) + printk(KERN_ERR "ERROR: parent span is not a superset " + "of domain->span\n"); + return 0; +} + +static void sched_domain_debug(struct sched_domain *sd, int cpu) +{ + int level = 0; + + if (!sched_domain_debug_enabled) + return; + + if (!sd) { + printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu); + return; + } + + printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); + + for (;;) { + if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) + break; + level++; + sd = sd->parent; + if (!sd) + break; + } +} +#else /* !CONFIG_SCHED_DEBUG */ +# define sched_domain_debug(sd, cpu) do { } while (0) +#endif /* CONFIG_SCHED_DEBUG */ + +static int sd_degenerate(struct sched_domain *sd) +{ + if (cpumask_weight(sched_domain_span(sd)) == 1) + return 1; + + /* Following flags need at least 2 groups */ + if (sd->flags & (SD_LOAD_BALANCE | + SD_BALANCE_NEWIDLE | + SD_BALANCE_FORK | + SD_BALANCE_EXEC | + SD_SHARE_CPUPOWER | + SD_SHARE_PKG_RESOURCES)) { + if (sd->groups != sd->groups->next) + return 0; + } + + /* Following flags don't use groups */ + if (sd->flags & (SD_WAKE_AFFINE)) + return 0; + + return 1; +} + +static int +sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) +{ + unsigned long cflags = sd->flags, pflags = parent->flags; + + if (sd_degenerate(parent)) + return 1; + + if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent))) + return 0; + + /* Flags needing groups don't count if only 1 group in parent */ + if (parent->groups == parent->groups->next) { + pflags &= ~(SD_LOAD_BALANCE | + SD_BALANCE_NEWIDLE | + SD_BALANCE_FORK | + SD_BALANCE_EXEC | + SD_SHARE_CPUPOWER | + SD_SHARE_PKG_RESOURCES); + if (nr_node_ids == 1) + pflags &= ~SD_SERIALIZE; + } + if (~cflags & pflags) + return 0; + + return 1; +} + +static void free_rootdomain(struct rcu_head *rcu) +{ + struct root_domain *rd = container_of(rcu, struct root_domain, rcu); + + cpupri_cleanup(&rd->cpupri); + free_cpumask_var(rd->rto_mask); + free_cpumask_var(rd->online); + free_cpumask_var(rd->span); + kfree(rd); +} + +static void rq_attach_root(struct rq *rq, struct root_domain *rd) +{ + struct root_domain *old_rd = NULL; + unsigned long flags; + + grq_lock_irqsave(&flags); + + if (rq->rd) { + old_rd = rq->rd; + + if (cpumask_test_cpu(rq->cpu, old_rd->online)) + set_rq_offline(rq); + + cpumask_clear_cpu(rq->cpu, old_rd->span); + + /* + * If we dont want to free the old_rt yet then + * set old_rd to NULL to skip the freeing later + * in this function: + */ + if (!atomic_dec_and_test(&old_rd->refcount)) + old_rd = NULL; + } + + atomic_inc(&rd->refcount); + rq->rd = rd; + + cpumask_set_cpu(rq->cpu, rd->span); + if (cpumask_test_cpu(rq->cpu, cpu_active_mask)) + set_rq_online(rq); + + grq_unlock_irqrestore(&flags); + + if (old_rd) + call_rcu_sched(&old_rd->rcu, free_rootdomain); +} + +static int init_rootdomain(struct root_domain *rd) +{ + memset(rd, 0, sizeof(*rd)); + + if (!alloc_cpumask_var(&rd->span, GFP_KERNEL)) + goto out; + if (!alloc_cpumask_var(&rd->online, GFP_KERNEL)) + goto free_span; + if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) + goto free_online; + + if (cpupri_init(&rd->cpupri) != 0) + goto free_rto_mask; + return 0; + +free_rto_mask: + free_cpumask_var(rd->rto_mask); +free_online: + free_cpumask_var(rd->online); +free_span: + free_cpumask_var(rd->span); +out: + return -ENOMEM; +} + +static void init_defrootdomain(void) +{ + init_rootdomain(&def_root_domain); + + atomic_set(&def_root_domain.refcount, 1); +} + +static struct root_domain *alloc_rootdomain(void) +{ + struct root_domain *rd; + + rd = kmalloc(sizeof(*rd), GFP_KERNEL); + if (!rd) + return NULL; + + if (init_rootdomain(rd) != 0) { + kfree(rd); + return NULL; + } + + return rd; +} + +static void free_sched_groups(struct sched_group *sg, int free_sgp) +{ + struct sched_group *tmp, *first; + + if (!sg) + return; + + first = sg; + do { + tmp = sg->next; + + if (free_sgp && atomic_dec_and_test(&sg->sgp->ref)) + kfree(sg->sgp); + + kfree(sg); + sg = tmp; + } while (sg != first); +} + +static void free_sched_domain(struct rcu_head *rcu) +{ + struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); + + /* + * If its an overlapping domain it has private groups, iterate and + * nuke them all. + */ + if (sd->flags & SD_OVERLAP) { + free_sched_groups(sd->groups, 1); + } else if (atomic_dec_and_test(&sd->groups->ref)) { + kfree(sd->groups->sgp); + kfree(sd->groups); + } + kfree(sd); +} + +static void destroy_sched_domain(struct sched_domain *sd, int cpu) +{ + call_rcu(&sd->rcu, free_sched_domain); +} + +static void destroy_sched_domains(struct sched_domain *sd, int cpu) +{ + for (; sd; sd = sd->parent) + destroy_sched_domain(sd, cpu); +} + +/* + * Attach the domain 'sd' to 'cpu' as its base domain. Callers must + * hold the hotplug lock. + */ +static void +cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + struct sched_domain *tmp; + + /* Remove the sched domains which do not contribute to scheduling. */ + for (tmp = sd; tmp; ) { + struct sched_domain *parent = tmp->parent; + if (!parent) + break; + + if (sd_parent_degenerate(tmp, parent)) { + tmp->parent = parent->parent; + if (parent->parent) + parent->parent->child = tmp; + destroy_sched_domain(parent, cpu); + } else + tmp = tmp->parent; + } + + if (sd && sd_degenerate(sd)) { + tmp = sd; + sd = sd->parent; + destroy_sched_domain(tmp, cpu); + if (sd) + sd->child = NULL; + } + + sched_domain_debug(sd, cpu); + + rq_attach_root(rq, rd); + tmp = rq->sd; + rcu_assign_pointer(rq->sd, sd); + destroy_sched_domains(tmp, cpu); +} + +/* cpus with isolated domains */ +static cpumask_var_t cpu_isolated_map; + +/* Setup the mask of cpus configured for isolated domains */ +static int __init isolated_cpu_setup(char *str) +{ + alloc_bootmem_cpumask_var(&cpu_isolated_map); + cpulist_parse(str, cpu_isolated_map); + return 1; +} + +__setup("isolcpus=", isolated_cpu_setup); + +#define SD_NODES_PER_DOMAIN 16 + +#ifdef CONFIG_NUMA + +/** + * find_next_best_node - find the next node to include in a sched_domain + * @node: node whose sched_domain we're building + * @used_nodes: nodes already in the sched_domain + * + * Find the next node to include in a given scheduling domain. Simply + * finds the closest node not already in the @used_nodes map. + * + * Should use nodemask_t. + */ +static int find_next_best_node(int node, nodemask_t *used_nodes) +{ + int i, n, val, min_val, best_node = -1; + + min_val = INT_MAX; + + for (i = 0; i < nr_node_ids; i++) { + /* Start at @node */ + n = (node + i) % nr_node_ids; + + if (!nr_cpus_node(n)) + continue; + + /* Skip already used nodes */ + if (node_isset(n, *used_nodes)) + continue; + + /* Simple min distance search */ + val = node_distance(node, n); + + if (val < min_val) { + min_val = val; + best_node = n; + } + } + + if (best_node != -1) + node_set(best_node, *used_nodes); + return best_node; +} + +/** + * sched_domain_node_span - get a cpumask for a node's sched_domain + * @node: node whose cpumask we're constructing + * @span: resulting cpumask + * + * Given a node, construct a good cpumask for its sched_domain to span. It + * should be one that prevents unnecessary balancing, but also spreads tasks + * out optimally. + */ +static void sched_domain_node_span(int node, struct cpumask *span) +{ + nodemask_t used_nodes; + int i; + + cpumask_clear(span); + nodes_clear(used_nodes); + + cpumask_or(span, span, cpumask_of_node(node)); + node_set(node, used_nodes); + + for (i = 1; i < SD_NODES_PER_DOMAIN; i++) { + int next_node = find_next_best_node(node, &used_nodes); + if (next_node < 0) + break; + cpumask_or(span, span, cpumask_of_node(next_node)); + } +} + +static const struct cpumask *cpu_node_mask(int cpu) +{ + lockdep_assert_held(&sched_domains_mutex); + + sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask); + + return sched_domains_tmpmask; +} + +static const struct cpumask *cpu_allnodes_mask(int cpu) +{ + return cpu_possible_mask; +} +#endif /* CONFIG_NUMA */ + +static const struct cpumask *cpu_cpu_mask(int cpu) +{ + return cpumask_of_node(cpu_to_node(cpu)); +} + +int sched_smt_power_savings = 0, sched_mc_power_savings = 0; + +struct sd_data { + struct sched_domain **__percpu sd; + struct sched_group **__percpu sg; + struct sched_group_power **__percpu sgp; +}; + +struct s_data { + struct sched_domain ** __percpu sd; + struct root_domain *rd; +}; + +enum s_alloc { + sa_rootdomain, + sa_sd, + sa_sd_storage, + sa_none, +}; + +struct sched_domain_topology_level; + +typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu); +typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); + +#define SDTL_OVERLAP 0x01 + +struct sched_domain_topology_level { + sched_domain_init_f init; + sched_domain_mask_f mask; + int flags; + struct sd_data data; +}; + +static int +build_overlap_sched_groups(struct sched_domain *sd, int cpu) +{ + struct sched_group *first = NULL, *last = NULL, *groups = NULL, *sg; + const struct cpumask *span = sched_domain_span(sd); + struct cpumask *covered = sched_domains_tmpmask; + struct sd_data *sdd = sd->private; + struct sched_domain *child; + int i; + + cpumask_clear(covered); + + for_each_cpu(i, span) { + struct cpumask *sg_span; + + if (cpumask_test_cpu(i, covered)) + continue; + + sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), + GFP_KERNEL, cpu_to_node(i)); + + if (!sg) + goto fail; + + sg_span = sched_group_cpus(sg); + + child = *per_cpu_ptr(sdd->sd, i); + if (child->child) { + child = child->child; + cpumask_copy(sg_span, sched_domain_span(child)); + } else + cpumask_set_cpu(i, sg_span); + + cpumask_or(covered, covered, sg_span); + + sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span)); + atomic_inc(&sg->sgp->ref); + + if (cpumask_test_cpu(cpu, sg_span)) + groups = sg; + + if (!first) + first = sg; + if (last) + last->next = sg; + last = sg; + last->next = first; + } + sd->groups = groups; + + return 0; + +fail: + free_sched_groups(first, 0); + + return -ENOMEM; +} + +static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg) +{ + struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); + struct sched_domain *child = sd->child; + + if (child) + cpu = cpumask_first(sched_domain_span(child)); + + if (sg) { + *sg = *per_cpu_ptr(sdd->sg, cpu); + (*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu); + atomic_set(&(*sg)->sgp->ref, 1); /* for claim_allocations */ + } + + return cpu; +} + +/* + * build_sched_groups will build a circular linked list of the groups + * covered by the given span, and will set each group's ->cpumask correctly, + * and ->cpu_power to 0. + * + * Assumes the sched_domain tree is fully constructed + */ +static int +build_sched_groups(struct sched_domain *sd, int cpu) +{ + struct sched_group *first = NULL, *last = NULL; + struct sd_data *sdd = sd->private; + const struct cpumask *span = sched_domain_span(sd); + struct cpumask *covered; + int i; + + get_group(cpu, sdd, &sd->groups); + atomic_inc(&sd->groups->ref); + + if (cpu != cpumask_first(sched_domain_span(sd))) + return 0; + + lockdep_assert_held(&sched_domains_mutex); + covered = sched_domains_tmpmask; + + cpumask_clear(covered); + + for_each_cpu(i, span) { + struct sched_group *sg; + int group = get_group(i, sdd, &sg); + int j; + + if (cpumask_test_cpu(i, covered)) + continue; + + cpumask_clear(sched_group_cpus(sg)); + sg->sgp->power = 0; + + for_each_cpu(j, span) { + if (get_group(j, sdd, NULL) != group) + continue; + + cpumask_set_cpu(j, covered); + cpumask_set_cpu(j, sched_group_cpus(sg)); + } + + if (!first) + first = sg; + if (last) + last->next = sg; + last = sg; + } + last->next = first; + + return 0; +} + +/* + * Initializers for schedule domains + * Non-inlined to reduce accumulated stack pressure in build_sched_domains() + */ + +#ifdef CONFIG_SCHED_DEBUG +# define SD_INIT_NAME(sd, type) sd->name = #type +#else +# define SD_INIT_NAME(sd, type) do { } while (0) +#endif + +#define SD_INIT_FUNC(type) \ +static noinline struct sched_domain * \ +sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \ +{ \ + struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \ + *sd = SD_##type##_INIT; \ + SD_INIT_NAME(sd, type); \ + sd->private = &tl->data; \ + return sd; \ +} + +SD_INIT_FUNC(CPU) +#ifdef CONFIG_NUMA + SD_INIT_FUNC(ALLNODES) + SD_INIT_FUNC(NODE) +#endif +#ifdef CONFIG_SCHED_SMT + SD_INIT_FUNC(SIBLING) +#endif +#ifdef CONFIG_SCHED_MC + SD_INIT_FUNC(MC) +#endif +#ifdef CONFIG_SCHED_BOOK + SD_INIT_FUNC(BOOK) +#endif + +static int default_relax_domain_level = -1; +int sched_domain_level_max; + +static int __init setup_relax_domain_level(char *str) +{ + unsigned long val; + + val = simple_strtoul(str, NULL, 0); + if (val < sched_domain_level_max) + default_relax_domain_level = val; + + return 1; +} +__setup("relax_domain_level=", setup_relax_domain_level); + +static void set_domain_attribute(struct sched_domain *sd, + struct sched_domain_attr *attr) +{ + int request; + + if (!attr || attr->relax_domain_level < 0) { + if (default_relax_domain_level < 0) + return; + else + request = default_relax_domain_level; + } else + request = attr->relax_domain_level; + if (request < sd->level) { + /* turn off idle balance on this domain */ + sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); + } else { + /* turn on idle balance on this domain */ + sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); + } +} + +static void __sdt_free(const struct cpumask *cpu_map); +static int __sdt_alloc(const struct cpumask *cpu_map); + +static void __free_domain_allocs(struct s_data *d, enum s_alloc what, + const struct cpumask *cpu_map) +{ + switch (what) { + case sa_rootdomain: + if (!atomic_read(&d->rd->refcount)) + free_rootdomain(&d->rd->rcu); /* fall through */ + case sa_sd: + free_percpu(d->sd); /* fall through */ + case sa_sd_storage: + __sdt_free(cpu_map); /* fall through */ + case sa_none: + break; + } +} + +static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, + const struct cpumask *cpu_map) +{ + memset(d, 0, sizeof(*d)); + + if (__sdt_alloc(cpu_map)) + return sa_sd_storage; + d->sd = alloc_percpu(struct sched_domain *); + if (!d->sd) + return sa_sd_storage; + d->rd = alloc_rootdomain(); + if (!d->rd) + return sa_sd; + return sa_rootdomain; +} + +/* + * NULL the sd_data elements we've used to build the sched_domain and + * sched_group structure so that the subsequent __free_domain_allocs() + * will not free the data we're using. + */ +static void claim_allocations(int cpu, struct sched_domain *sd) +{ + struct sd_data *sdd = sd->private; + + WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); + *per_cpu_ptr(sdd->sd, cpu) = NULL; + + if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref)) + *per_cpu_ptr(sdd->sg, cpu) = NULL; + + if (atomic_read(&(*per_cpu_ptr(sdd->sgp, cpu))->ref)) + *per_cpu_ptr(sdd->sgp, cpu) = NULL; +} + +#ifdef CONFIG_SCHED_SMT +static const struct cpumask *cpu_smt_mask(int cpu) +{ + return topology_thread_cpumask(cpu); +} +#endif + +/* + * Topology list, bottom-up. + */ +static struct sched_domain_topology_level default_topology[] = { +#ifdef CONFIG_SCHED_SMT + { sd_init_SIBLING, cpu_smt_mask, }, +#endif +#ifdef CONFIG_SCHED_MC + { sd_init_MC, cpu_coregroup_mask, }, +#endif +#ifdef CONFIG_SCHED_BOOK + { sd_init_BOOK, cpu_book_mask, }, +#endif + { sd_init_CPU, cpu_cpu_mask, }, +#ifdef CONFIG_NUMA + { sd_init_NODE, cpu_node_mask, SDTL_OVERLAP, }, + { sd_init_ALLNODES, cpu_allnodes_mask, }, +#endif + { NULL, }, +}; + +static struct sched_domain_topology_level *sched_domain_topology = default_topology; + +static int __sdt_alloc(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + sdd->sd = alloc_percpu(struct sched_domain *); + if (!sdd->sd) + return -ENOMEM; + + sdd->sg = alloc_percpu(struct sched_group *); + if (!sdd->sg) + return -ENOMEM; + + sdd->sgp = alloc_percpu(struct sched_group_power *); + if (!sdd->sgp) + return -ENOMEM; + + for_each_cpu(j, cpu_map) { + struct sched_domain *sd; + struct sched_group *sg; + struct sched_group_power *sgp; + + sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sd) + return -ENOMEM; + + *per_cpu_ptr(sdd->sd, j) = sd; + + sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sg) + return -ENOMEM; + + *per_cpu_ptr(sdd->sg, j) = sg; + + sgp = kzalloc_node(sizeof(struct sched_group_power), + GFP_KERNEL, cpu_to_node(j)); + if (!sgp) + return -ENOMEM; + + *per_cpu_ptr(sdd->sgp, j) = sgp; + } + } + + return 0; +} + +static void __sdt_free(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + for_each_cpu(j, cpu_map) { + struct sched_domain *sd = *per_cpu_ptr(sdd->sd, j); + if (sd && (sd->flags & SD_OVERLAP)) + free_sched_groups(sd->groups, 0); + kfree(*per_cpu_ptr(sdd->sd, j)); + kfree(*per_cpu_ptr(sdd->sg, j)); + kfree(*per_cpu_ptr(sdd->sgp, j)); + } + free_percpu(sdd->sd); + free_percpu(sdd->sg); + free_percpu(sdd->sgp); + } +} + +struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, + struct s_data *d, const struct cpumask *cpu_map, + struct sched_domain_attr *attr, struct sched_domain *child, + int cpu) +{ + struct sched_domain *sd = tl->init(tl, cpu); + if (!sd) + return child; + + set_domain_attribute(sd, attr); + cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); + if (child) { + sd->level = child->level + 1; + sched_domain_level_max = max(sched_domain_level_max, sd->level); + child->parent = sd; + } + sd->child = child; + + return sd; +} + +/* + * Build sched domains for a given set of cpus and attach the sched domains + * to the individual cpus + */ +static int build_sched_domains(const struct cpumask *cpu_map, + struct sched_domain_attr *attr) +{ + enum s_alloc alloc_state = sa_none; + struct sched_domain *sd; + struct s_data d; + int i, ret = -ENOMEM; + + alloc_state = __visit_domain_allocation_hell(&d, cpu_map); + if (alloc_state != sa_rootdomain) + goto error; + + /* Set up domains for cpus specified by the cpu_map. */ + for_each_cpu(i, cpu_map) { + struct sched_domain_topology_level *tl; + + sd = NULL; + for (tl = sched_domain_topology; tl->init; tl++) { + sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); + if (tl->flags & SDTL_OVERLAP) + sd->flags |= SD_OVERLAP; + if (cpumask_equal(cpu_map, sched_domain_span(sd))) + break; + } + + while (sd->child) + sd = sd->child; + + *per_cpu_ptr(d.sd, i) = sd; + } + + /* Build the groups for the domains */ + for_each_cpu(i, cpu_map) { + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + sd->span_weight = cpumask_weight(sched_domain_span(sd)); + if (sd->flags & SD_OVERLAP) { + if (build_overlap_sched_groups(sd, i)) + goto error; + } else { + if (build_sched_groups(sd, i)) + goto error; + } + } + } + + /* Calculate CPU power for physical packages and nodes */ + for (i = nr_cpumask_bits-1; i >= 0; i--) { + if (!cpumask_test_cpu(i, cpu_map)) + continue; + + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + claim_allocations(i, sd); + } + } + + /* Attach the domains */ + rcu_read_lock(); + for_each_cpu(i, cpu_map) { + sd = *per_cpu_ptr(d.sd, i); + cpu_attach_domain(sd, d.rd, i); + } + rcu_read_unlock(); + + ret = 0; +error: + __free_domain_allocs(&d, alloc_state, cpu_map); + return ret; +} + +static cpumask_var_t *doms_cur; /* current sched domains */ +static int ndoms_cur; /* number of sched domains in 'doms_cur' */ +static struct sched_domain_attr *dattr_cur; + /* attribues of custom domains in 'doms_cur' */ + +/* + * Special case: If a kmalloc of a doms_cur partition (array of + * cpumask) fails, then fallback to a single sched domain, + * as determined by the single cpumask fallback_doms. + */ +static cpumask_var_t fallback_doms; + +/* + * arch_update_cpu_topology lets virtualized architectures update the + * cpu core maps. It is supposed to return 1 if the topology changed + * or 0 if it stayed the same. + */ +int __attribute__((weak)) arch_update_cpu_topology(void) +{ + return 0; +} + +cpumask_var_t *alloc_sched_domains(unsigned int ndoms) +{ + int i; + cpumask_var_t *doms; + + doms = kmalloc(sizeof(*doms) * ndoms, GFP_KERNEL); + if (!doms) + return NULL; + for (i = 0; i < ndoms; i++) { + if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) { + free_sched_domains(doms, i); + return NULL; + } + } + return doms; +} + +void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) +{ + unsigned int i; + for (i = 0; i < ndoms; i++) + free_cpumask_var(doms[i]); + kfree(doms); +} + +/* + * Set up scheduler domains and groups. Callers must hold the hotplug lock. + * For now this just excludes isolated cpus, but could be used to + * exclude other special cases in the future. + */ +static int init_sched_domains(const struct cpumask *cpu_map) +{ + int err; + + arch_update_cpu_topology(); + ndoms_cur = 1; + doms_cur = alloc_sched_domains(ndoms_cur); + if (!doms_cur) + doms_cur = &fallback_doms; + cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); + dattr_cur = NULL; + err = build_sched_domains(doms_cur[0], NULL); + register_sched_domain_sysctl(); + + return err; +} + +/* + * Detach sched domains from a group of cpus specified in cpu_map + * These cpus will now be attached to the NULL domain + */ +static void detach_destroy_domains(const struct cpumask *cpu_map) +{ + int i; + + rcu_read_lock(); + for_each_cpu(i, cpu_map) + cpu_attach_domain(NULL, &def_root_domain, i); + rcu_read_unlock(); +} + +/* handle null as "default" */ +static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, + struct sched_domain_attr *new, int idx_new) +{ + struct sched_domain_attr tmp; + + /* fast path */ + if (!new && !cur) + return 1; + + tmp = SD_ATTR_INIT; + return !memcmp(cur ? (cur + idx_cur) : &tmp, + new ? (new + idx_new) : &tmp, + sizeof(struct sched_domain_attr)); +} + +/* + * Partition sched domains as specified by the 'ndoms_new' + * cpumasks in the array doms_new[] of cpumasks. This compares + * doms_new[] to the current sched domain partitioning, doms_cur[]. + * It destroys each deleted domain and builds each new domain. + * + * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'. + * The masks don't intersect (don't overlap.) We should setup one + * sched domain for each mask. CPUs not in any of the cpumasks will + * not be load balanced. If the same cpumask appears both in the + * current 'doms_cur' domains and in the new 'doms_new', we can leave + * it as it is. + * + * The passed in 'doms_new' should be allocated using + * alloc_sched_domains. This routine takes ownership of it and will + * free_sched_domains it when done with it. If the caller failed the + * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1, + * and partition_sched_domains() will fallback to the single partition + * 'fallback_doms', it also forces the domains to be rebuilt. + * + * If doms_new == NULL it will be replaced with cpu_online_mask. + * ndoms_new == 0 is a special case for destroying existing domains, + * and it will not create the default domain. + * + * Call with hotplug lock held + */ +void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], + struct sched_domain_attr *dattr_new) +{ + int i, j, n; + int new_topology; + + mutex_lock(&sched_domains_mutex); + + /* always unregister in case we don't destroy any domains */ + unregister_sched_domain_sysctl(); + + /* Let architecture update cpu core mappings. */ + new_topology = arch_update_cpu_topology(); + + n = doms_new ? ndoms_new : 0; + + /* Destroy deleted domains */ + for (i = 0; i < ndoms_cur; i++) { + for (j = 0; j < n && !new_topology; j++) { + if (cpumask_equal(doms_cur[i], doms_new[j]) + && dattrs_equal(dattr_cur, i, dattr_new, j)) + goto match1; + } + /* no match - a current sched domain not in new doms_new[] */ + detach_destroy_domains(doms_cur[i]); +match1: + ; + } + + if (doms_new == NULL) { + ndoms_cur = 0; + doms_new = &fallback_doms; + cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map); + WARN_ON_ONCE(dattr_new); + } + + /* Build new domains */ + for (i = 0; i < ndoms_new; i++) { + for (j = 0; j < ndoms_cur && !new_topology; j++) { + if (cpumask_equal(doms_new[i], doms_cur[j]) + && dattrs_equal(dattr_new, i, dattr_cur, j)) + goto match2; + } + /* no match - add a new doms_new */ + build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); +match2: + ; + } + + /* Remember the new sched domains */ + if (doms_cur != &fallback_doms) + free_sched_domains(doms_cur, ndoms_cur); + kfree(dattr_cur); /* kfree(NULL) is safe */ + doms_cur = doms_new; + dattr_cur = dattr_new; + ndoms_cur = ndoms_new; + + register_sched_domain_sysctl(); + + mutex_unlock(&sched_domains_mutex); +} + +#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) +static void reinit_sched_domains(void) +{ + get_online_cpus(); + + /* Destroy domains first to force the rebuild */ + partition_sched_domains(0, NULL, NULL); + + rebuild_sched_domains(); + put_online_cpus(); +} + +static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) +{ + unsigned int level = 0; + + if (sscanf(buf, "%u", &level) != 1) + return -EINVAL; + + /* + * level is always be positive so don't check for + * level < POWERSAVINGS_BALANCE_NONE which is 0 + * What happens on 0 or 1 byte write, + * need to check for count as well? + */ + + if (level >= MAX_POWERSAVINGS_BALANCE_LEVELS) + return -EINVAL; + + if (smt) + sched_smt_power_savings = level; + else + sched_mc_power_savings = level; + + reinit_sched_domains(); + + return count; +} + +#ifdef CONFIG_SCHED_MC +static ssize_t sched_mc_power_savings_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", sched_mc_power_savings); +} +static ssize_t sched_mc_power_savings_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + return sched_power_savings_store(buf, count, 0); +} +static DEVICE_ATTR(sched_mc_power_savings, 0644, + sched_mc_power_savings_show, + sched_mc_power_savings_store); +#endif + +#ifdef CONFIG_SCHED_SMT +static ssize_t sched_smt_power_savings_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", sched_smt_power_savings); +} +static ssize_t sched_smt_power_savings_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + return sched_power_savings_store(buf, count, 1); +} +static DEVICE_ATTR(sched_smt_power_savings, 0644, + sched_smt_power_savings_show, + sched_smt_power_savings_store); +#endif + +int __init sched_create_sysfs_power_savings_entries(struct device *dev) +{ + int err = 0; + +#ifdef CONFIG_SCHED_SMT + if (smt_capable()) + err = device_create_file(dev, &dev_attr_sched_smt_power_savings); +#endif +#ifdef CONFIG_SCHED_MC + if (!err && mc_capable()) + err = device_create_file(dev, &dev_attr_sched_mc_power_savings); +#endif + return err; +} +#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */ + +/* + * Update cpusets according to cpu_active mask. If cpusets are + * disabled, cpuset_update_active_cpus() becomes a simple wrapper + * around partition_sched_domains(). + */ +static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, + void *hcpu) +{ + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_ONLINE: + case CPU_STARTING: + case CPU_DOWN_FAILED: + cpuset_update_active_cpus(); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, + void *hcpu) +{ + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_DOWN_PREPARE: + cpuset_update_active_cpus(); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC) +/* + * Cheaper version of the below functions in case support for SMT and MC is + * compiled in but CPUs have no siblings. + */ +static bool sole_cpu_idle(int cpu) +{ + return rq_idle(cpu_rq(cpu)); +} +#endif +#ifdef CONFIG_SCHED_SMT +/* All this CPU's SMT siblings are idle */ +static bool siblings_cpu_idle(int cpu) +{ + return cpumask_subset(&(cpu_rq(cpu)->smt_siblings), + &grq.cpu_idle_map); +} +#endif +#ifdef CONFIG_SCHED_MC +/* All this CPU's shared cache siblings are idle */ +static bool cache_cpu_idle(int cpu) +{ + return cpumask_subset(&(cpu_rq(cpu)->cache_siblings), + &grq.cpu_idle_map); +} +#endif + +enum sched_domain_level { + SD_LV_NONE = 0, + SD_LV_SIBLING, + SD_LV_MC, + SD_LV_BOOK, + SD_LV_CPU, + SD_LV_NODE, + SD_LV_ALLNODES, + SD_LV_MAX +}; + +void __init sched_init_smp(void) +{ + struct sched_domain *sd; + int cpu; + + cpumask_var_t non_isolated_cpus; + + alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); + alloc_cpumask_var(&fallback_doms, GFP_KERNEL); + + get_online_cpus(); + mutex_lock(&sched_domains_mutex); + init_sched_domains(cpu_active_mask); + cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map); + if (cpumask_empty(non_isolated_cpus)) + cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); + mutex_unlock(&sched_domains_mutex); + put_online_cpus(); + + hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE); + hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE); + + /* Move init over to a non-isolated CPU */ + if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0) + BUG(); + free_cpumask_var(non_isolated_cpus); + + grq_lock_irq(); + /* + * Set up the relative cache distance of each online cpu from each + * other in a simple array for quick lookup. Locality is determined + * by the closest sched_domain that CPUs are separated by. CPUs with + * shared cache in SMT and MC are treated as local. Separate CPUs + * (within the same package or physically) within the same node are + * treated as not local. CPUs not even in the same domain (different + * nodes) are treated as very distant. + */ + for_each_online_cpu(cpu) { + struct rq *rq = cpu_rq(cpu); + for_each_domain(cpu, sd) { + int locality, other_cpu; + +#ifdef CONFIG_SCHED_SMT + if (sd->level == SD_LV_SIBLING) { + for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) + cpumask_set_cpu(other_cpu, &rq->smt_siblings); + } +#endif +#ifdef CONFIG_SCHED_MC + if (sd->level == SD_LV_MC) { + for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) + cpumask_set_cpu(other_cpu, &rq->cache_siblings); + } +#endif + if (sd->level <= SD_LV_SIBLING) + locality = 1; + else if (sd->level <= SD_LV_MC) + locality = 2; + else if (sd->level <= SD_LV_NODE) + locality = 3; + else + continue; + + for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) { + if (locality < rq->cpu_locality[other_cpu]) + rq->cpu_locality[other_cpu] = locality; + } + } + +/* + * Each runqueue has its own function in case it doesn't have + * siblings of its own allowing mixed topologies. + */ +#ifdef CONFIG_SCHED_SMT + if (cpus_weight(rq->smt_siblings) > 1) + rq->siblings_idle = siblings_cpu_idle; +#endif +#ifdef CONFIG_SCHED_MC + if (cpus_weight(rq->cache_siblings) > 1) + rq->cache_idle = cache_cpu_idle; +#endif + } + grq_unlock_irq(); +} +#else +void __init sched_init_smp(void) +{ +} +#endif /* CONFIG_SMP */ + +unsigned int sysctl_timer_migration = 1; + +int in_sched_functions(unsigned long addr) +{ + return in_lock_functions(addr) || + (addr >= (unsigned long)__sched_text_start + && addr < (unsigned long)__sched_text_end); +} + +void __init sched_init(void) +{ + int i; + struct rq *rq; + + print_scheduler_version(); + + raw_spin_lock_init(&grq.lock); + grq.nr_running = grq.nr_uninterruptible = grq.nr_switches = 0; + grq.noc = 1; +#ifdef CONFIG_SMP + init_defrootdomain(); + grq.qnr = grq.idle_cpus = 0; + cpumask_clear(&grq.cpu_idle_map); + +#else + uprq = &per_cpu(runqueues, 0); +#endif + for_each_possible_cpu(i) { + rq = cpu_rq(i); + rq->user_pc = rq->nice_pc = rq->softirq_pc = rq->system_pc = + rq->iowait_pc = rq->idle_pc = 0; + rq->last_run_scale = 0; +#ifdef CONFIG_SMP + rq->sticky_task = NULL; + rq->sd = NULL; + rq->rd = NULL; + rq->online = false; + rq->cpu = i; + rq_attach_root(rq, &def_root_domain); +#endif + atomic_set(&rq->nr_iowait, 0); + } + +#ifdef CONFIG_SMP + nr_cpu_ids = i; + /* + * Set the base locality for cpu cache distance calculation to + * "distant" (3). Make sure the distance from a CPU to itself is 0. + */ + for_each_possible_cpu(i) { + int j; + + rq = cpu_rq(i); +#ifdef CONFIG_SCHED_SMT + cpumask_clear(&rq->smt_siblings); + cpumask_set_cpu(i, &rq->smt_siblings); + rq->siblings_idle = sole_cpu_idle; + cpumask_set_cpu(i, &rq->smt_siblings); +#endif +#ifdef CONFIG_SCHED_MC + cpumask_clear(&rq->cache_siblings); + cpumask_set_cpu(i, &rq->cache_siblings); + rq->cache_idle = sole_cpu_idle; + cpumask_set_cpu(i, &rq->cache_siblings); +#endif + rq->cpu_locality = kmalloc(nr_cpu_ids * sizeof(int *), GFP_ATOMIC); + for_each_possible_cpu(j) { + if (i == j) + rq->cpu_locality[j] = 0; + else + rq->cpu_locality[j] = 4; + } + } +#endif + + for (i = 0; i < PRIO_LIMIT; i++) + INIT_LIST_HEAD(grq.queue + i); + /* delimiter for bitsearch */ + __set_bit(PRIO_LIMIT, grq.prio_bitmap); + +#ifdef CONFIG_PREEMPT_NOTIFIERS + INIT_HLIST_HEAD(&init_task.preempt_notifiers); +#endif + +#ifdef CONFIG_RT_MUTEXES + plist_head_init(&init_task.pi_waiters); +#endif + + /* + * The boot idle thread does lazy MMU switching as well: + */ + atomic_inc(&init_mm.mm_count); + enter_lazy_tlb(&init_mm, current); + + /* + * Make us the idle thread. Technically, schedule() should not be + * called from this thread, however somewhere below it might be, + * but because we are the idle thread, we just pick up running again + * when this runqueue becomes "idle". + */ + init_idle(current, smp_processor_id()); + +#ifdef CONFIG_SMP + zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); + /* May be allocated at isolcpus cmdline parse time */ + if (cpu_isolated_map == NULL) + zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); +#endif /* SMP */ +} + +#ifdef CONFIG_DEBUG_ATOMIC_SLEEP +static inline int preempt_count_equals(int preempt_offset) +{ + int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); + + return (nested == preempt_offset); +} + +void __might_sleep(const char *file, int line, int preempt_offset) +{ + static unsigned long prev_jiffy; /* ratelimiting */ + + rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */ + if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) || + system_state != SYSTEM_RUNNING || oops_in_progress) + return; + if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) + return; + prev_jiffy = jiffies; + + printk(KERN_ERR + "BUG: sleeping function called from invalid context at %s:%d\n", + file, line); + printk(KERN_ERR + "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", + in_atomic(), irqs_disabled(), + current->pid, current->comm); + + debug_show_held_locks(current); + if (irqs_disabled()) + print_irqtrace_events(current); + dump_stack(); +} +EXPORT_SYMBOL(__might_sleep); +#endif + +#ifdef CONFIG_MAGIC_SYSRQ +void normalize_rt_tasks(void) +{ + struct task_struct *g, *p; + unsigned long flags; + struct rq *rq; + int queued; + + read_lock_irq(&tasklist_lock); + + do_each_thread(g, p) { + if (!rt_task(p)) + continue; + + raw_spin_lock_irqsave(&p->pi_lock, flags); + rq = __task_grq_lock(p); + + queued = task_queued(p); + __setscheduler(p, rq, SCHED_NORMAL, 0); + if (queued) { + try_preempt(p, rq); + } + + __task_grq_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + } while_each_thread(g, p); + + read_unlock_irq(&tasklist_lock); +} +#endif /* CONFIG_MAGIC_SYSRQ */ + +#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) +/* + * These functions are only useful for the IA64 MCA handling, or kdb. + * + * They can only be called when the whole system has been + * stopped - every CPU needs to be quiescent, and no scheduling + * activity can take place. Using them for anything else would + * be a serious bug, and as a result, they aren't even visible + * under any other configuration. + */ + +/** + * curr_task - return the current task for a given cpu. + * @cpu: the processor in question. + * + * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! + */ +struct task_struct *curr_task(int cpu) +{ + return cpu_curr(cpu); +} + +#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */ + +#ifdef CONFIG_IA64 +/** + * set_curr_task - set the current task for a given cpu. + * @cpu: the processor in question. + * @p: the task pointer to set. + * + * Description: This function must only be used when non-maskable interrupts + * are serviced on a separate stack. It allows the architecture to switch the + * notion of the current task on a cpu in a non-blocking manner. This function + * must be called with all CPU's synchronised, and interrupts disabled, the + * and caller must save the original value of the current task (see + * curr_task() above) and restore that value before reenabling interrupts and + * re-starting the system. + * + * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! + */ +void set_curr_task(int cpu, struct task_struct *p) +{ + cpu_curr(cpu) = p; +} + +#endif + +/* + * Use precise platform statistics if available: + */ +#ifdef CONFIG_VIRT_CPU_ACCOUNTING +void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + *ut = p->utime; + *st = p->stime; +} + +void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + struct task_cputime cputime; + + thread_group_cputime(p, &cputime); + + *ut = cputime.utime; + *st = cputime.stime; +} +#else + +void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + cputime_t rtime, utime = p->utime, total = utime + p->stime; + + rtime = nsecs_to_cputime(p->sched_time); + + if (total) { + u64 temp; + + temp = (u64)(rtime * utime); + do_div(temp, total); + utime = (cputime_t)temp; + } else + utime = rtime; + + /* + * Compare with previous values, to keep monotonicity: + */ + p->prev_utime = max(p->prev_utime, utime); + p->prev_stime = max(p->prev_stime, (rtime - p->prev_utime)); + + *ut = p->prev_utime; + *st = p->prev_stime; +} + +/* + * Must be called with siglock held. + */ +void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + struct signal_struct *sig = p->signal; + struct task_cputime cputime; + cputime_t rtime, utime, total; + + thread_group_cputime(p, &cputime); + + total = cputime.utime + cputime.stime; + rtime = nsecs_to_cputime(cputime.sum_exec_runtime); + + if (total) { + u64 temp; + + temp = (u64)(rtime * cputime.utime); + do_div(temp, total); + utime = (cputime_t)temp; + } else + utime = rtime; + + sig->prev_utime = max(sig->prev_utime, utime); + sig->prev_stime = max(sig->prev_stime, (rtime - sig->prev_utime)); + + *ut = sig->prev_utime; + *st = sig->prev_stime; +} +#endif + +inline cputime_t task_gtime(struct task_struct *p) +{ + return p->gtime; +} + +void __cpuinit init_idle_bootup_task(struct task_struct *idle) +{} + +#ifdef CONFIG_SCHED_DEBUG +void proc_sched_show_task(struct task_struct *p, struct seq_file *m) +{} + +void proc_sched_set_task(struct task_struct *p) +{} +#endif + +#ifdef CONFIG_SMP +unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu) +{ + return SCHED_LOAD_SCALE; +} + +unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu) +{ + unsigned long weight = cpumask_weight(sched_domain_span(sd)); + unsigned long smt_gain = sd->smt_gain; + + smt_gain /= weight; + + return smt_gain; +} +#endif diff -ruN linux-3.4.1/kernel/sched/stats.c linux-3.4.1-RIFS/kernel/sched/stats.c --- linux-3.4.1/kernel/sched/stats.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/sched/stats.c 1970-01-01 08:00:00.000000000 +0800 @@ -1,111 +0,0 @@ - -#include <linux/slab.h> -#include <linux/fs.h> -#include <linux/seq_file.h> -#include <linux/proc_fs.h> - -#include "sched.h" - -/* - * bump this up when changing the output format or the meaning of an existing - * format, so that tools can adapt (or abort) - */ -#define SCHEDSTAT_VERSION 15 - -static int show_schedstat(struct seq_file *seq, void *v) -{ - int cpu; - int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9; - char *mask_str = kmalloc(mask_len, GFP_KERNEL); - - if (mask_str == NULL) - return -ENOMEM; - - seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION); - seq_printf(seq, "timestamp %lu\n", jiffies); - for_each_online_cpu(cpu) { - struct rq *rq = cpu_rq(cpu); -#ifdef CONFIG_SMP - struct sched_domain *sd; - int dcount = 0; -#endif - - /* runqueue-specific stats */ - seq_printf(seq, - "cpu%d %u 0 %u %u %u %u %llu %llu %lu", - cpu, rq->yld_count, - rq->sched_count, rq->sched_goidle, - rq->ttwu_count, rq->ttwu_local, - rq->rq_cpu_time, - rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount); - - seq_printf(seq, "\n"); - -#ifdef CONFIG_SMP - /* domain-specific stats */ - rcu_read_lock(); - for_each_domain(cpu, sd) { - enum cpu_idle_type itype; - - cpumask_scnprintf(mask_str, mask_len, - sched_domain_span(sd)); - seq_printf(seq, "domain%d %s", dcount++, mask_str); - for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES; - itype++) { - seq_printf(seq, " %u %u %u %u %u %u %u %u", - sd->lb_count[itype], - sd->lb_balanced[itype], - sd->lb_failed[itype], - sd->lb_imbalance[itype], - sd->lb_gained[itype], - sd->lb_hot_gained[itype], - sd->lb_nobusyq[itype], - sd->lb_nobusyg[itype]); - } - seq_printf(seq, - " %u %u %u %u %u %u %u %u %u %u %u %u\n", - sd->alb_count, sd->alb_failed, sd->alb_pushed, - sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed, - sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed, - sd->ttwu_wake_remote, sd->ttwu_move_affine, - sd->ttwu_move_balance); - } - rcu_read_unlock(); -#endif - } - kfree(mask_str); - return 0; -} - -static int schedstat_open(struct inode *inode, struct file *file) -{ - unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32); - char *buf = kmalloc(size, GFP_KERNEL); - struct seq_file *m; - int res; - - if (!buf) - return -ENOMEM; - res = single_open(file, show_schedstat, NULL); - if (!res) { - m = file->private_data; - m->buf = buf; - m->size = size; - } else - kfree(buf); - return res; -} - -static const struct file_operations proc_schedstat_operations = { - .open = schedstat_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init proc_schedstat_init(void) -{ - proc_create("schedstat", 0, NULL, &proc_schedstat_operations); - return 0; -} -module_init(proc_schedstat_init); diff -ruN linux-3.4.1/kernel/sched/stats.h linux-3.4.1-RIFS/kernel/sched/stats.h --- linux-3.4.1/kernel/sched/stats.h 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/sched/stats.h 2012-06-06 14:43:02.000000000 +0800 @@ -1,231 +0,0 @@ - -#ifdef CONFIG_SCHEDSTATS - -/* - * Expects runqueue lock to be held for atomicity of update - */ -static inline void -rq_sched_info_arrive(struct rq *rq, unsigned long long delta) -{ - if (rq) { - rq->rq_sched_info.run_delay += delta; - rq->rq_sched_info.pcount++; - } -} - -/* - * Expects runqueue lock to be held for atomicity of update - */ -static inline void -rq_sched_info_depart(struct rq *rq, unsigned long long delta) -{ - if (rq) - rq->rq_cpu_time += delta; -} - -static inline void -rq_sched_info_dequeued(struct rq *rq, unsigned long long delta) -{ - if (rq) - rq->rq_sched_info.run_delay += delta; -} -# define schedstat_inc(rq, field) do { (rq)->field++; } while (0) -# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0) -# define schedstat_set(var, val) do { var = (val); } while (0) -#else /* !CONFIG_SCHEDSTATS */ -static inline void -rq_sched_info_arrive(struct rq *rq, unsigned long long delta) -{} -static inline void -rq_sched_info_dequeued(struct rq *rq, unsigned long long delta) -{} -static inline void -rq_sched_info_depart(struct rq *rq, unsigned long long delta) -{} -# define schedstat_inc(rq, field) do { } while (0) -# define schedstat_add(rq, field, amt) do { } while (0) -# define schedstat_set(var, val) do { } while (0) -#endif - -#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) -static inline void sched_info_reset_dequeued(struct task_struct *t) -{ - t->sched_info.last_queued = 0; -} - -/* - * We are interested in knowing how long it was from the *first* time a - * task was queued to the time that it finally hit a cpu, we call this routine - * from dequeue_task() to account for possible rq->clock skew across cpus. The - * delta taken on each cpu would annul the skew. - */ -static inline void sched_info_dequeued(struct task_struct *t) -{ - unsigned long long now = task_rq(t)->clock, delta = 0; - - if (unlikely(sched_info_on())) - if (t->sched_info.last_queued) - delta = now - t->sched_info.last_queued; - sched_info_reset_dequeued(t); - t->sched_info.run_delay += delta; - - rq_sched_info_dequeued(task_rq(t), delta); -} - -/* - * Called when a task finally hits the cpu. We can now calculate how - * long it was waiting to run. We also note when it began so that we - * can keep stats on how long its timeslice is. - */ -static void sched_info_arrive(struct task_struct *t) -{ - unsigned long long now = task_rq(t)->clock, delta = 0; - - if (t->sched_info.last_queued) - delta = now - t->sched_info.last_queued; - sched_info_reset_dequeued(t); - t->sched_info.run_delay += delta; - t->sched_info.last_arrival = now; - t->sched_info.pcount++; - - rq_sched_info_arrive(task_rq(t), delta); -} - -/* - * This function is only called from enqueue_task(), but also only updates - * the timestamp if it is already not set. It's assumed that - * sched_info_dequeued() will clear that stamp when appropriate. - */ -static inline void sched_info_queued(struct task_struct *t) -{ - if (unlikely(sched_info_on())) - if (!t->sched_info.last_queued) - t->sched_info.last_queued = task_rq(t)->clock; -} - -/* - * Called when a process ceases being the active-running process, either - * voluntarily or involuntarily. Now we can calculate how long we ran. - * Also, if the process is still in the TASK_RUNNING state, call - * sched_info_queued() to mark that it has now again started waiting on - * the runqueue. - */ -static inline void sched_info_depart(struct task_struct *t) -{ - unsigned long long delta = task_rq(t)->clock - - t->sched_info.last_arrival; - - rq_sched_info_depart(task_rq(t), delta); - - if (t->state == TASK_RUNNING) - sched_info_queued(t); -} - -/* - * Called when tasks are switched involuntarily due, typically, to expiring - * their time slice. (This may also be called when switching to or from - * the idle task.) We are only called when prev != next. - */ -static inline void -__sched_info_switch(struct task_struct *prev, struct task_struct *next) -{ - struct rq *rq = task_rq(prev); - - /* - * prev now departs the cpu. It's not interesting to record - * stats about how efficient we were at scheduling the idle - * process, however. - */ - if (prev != rq->idle) - sched_info_depart(prev); - - if (next != rq->idle) - sched_info_arrive(next); -} -static inline void -sched_info_switch(struct task_struct *prev, struct task_struct *next) -{ - if (unlikely(sched_info_on())) - __sched_info_switch(prev, next); -} -#else -#define sched_info_queued(t) do { } while (0) -#define sched_info_reset_dequeued(t) do { } while (0) -#define sched_info_dequeued(t) do { } while (0) -#define sched_info_switch(t, next) do { } while (0) -#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */ - -/* - * The following are functions that support scheduler-internal time accounting. - * These functions are generally called at the timer tick. None of this depends - * on CONFIG_SCHEDSTATS. - */ - -/** - * account_group_user_time - Maintain utime for a thread group. - * - * @tsk: Pointer to task structure. - * @cputime: Time value by which to increment the utime field of the - * thread_group_cputime structure. - * - * If thread group time is being maintained, get the structure for the - * running CPU and update the utime field there. - */ -static inline void account_group_user_time(struct task_struct *tsk, - cputime_t cputime) -{ - struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; - - if (!cputimer->running) - return; - - raw_spin_lock(&cputimer->lock); - cputimer->cputime.utime += cputime; - raw_spin_unlock(&cputimer->lock); -} - -/** - * account_group_system_time - Maintain stime for a thread group. - * - * @tsk: Pointer to task structure. - * @cputime: Time value by which to increment the stime field of the - * thread_group_cputime structure. - * - * If thread group time is being maintained, get the structure for the - * running CPU and update the stime field there. - */ -static inline void account_group_system_time(struct task_struct *tsk, - cputime_t cputime) -{ - struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; - - if (!cputimer->running) - return; - - raw_spin_lock(&cputimer->lock); - cputimer->cputime.stime += cputime; - raw_spin_unlock(&cputimer->lock); -} - -/** - * account_group_exec_runtime - Maintain exec runtime for a thread group. - * - * @tsk: Pointer to task structure. - * @ns: Time value by which to increment the sum_exec_runtime field - * of the thread_group_cputime structure. - * - * If thread group time is being maintained, get the structure for the - * running CPU and update the sum_exec_runtime field there. - */ -static inline void account_group_exec_runtime(struct task_struct *tsk, - unsigned long long ns) -{ - struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; - - if (!cputimer->running) - return; - - raw_spin_lock(&cputimer->lock); - cputimer->cputime.sum_exec_runtime += ns; - raw_spin_unlock(&cputimer->lock); -} diff -ruN linux-3.4.1/kernel/sysctl.c linux-3.4.1-RIFS/kernel/sysctl.c --- linux-3.4.1/kernel/sysctl.c 2012-06-01 15:18:44.000000000 +0800 +++ linux-3.4.1-RIFS/kernel/sysctl.c 2012-06-15 23:46:44.000000000 +0800 @@ -242,6 +242,7 @@ }; #ifdef CONFIG_SCHED_DEBUG +#ifndef CONFIG_SCHED_RIFS static int min_sched_granularity_ns = 100000; /* 100 usecs */ static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ static int min_wakeup_granularity_ns; /* 0 usecs */ @@ -249,6 +250,7 @@ static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE; static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1; #endif +#endif #ifdef CONFIG_COMPACTION static int min_extfrag_threshold; @@ -256,14 +258,8 @@ #endif static struct ctl_table kern_table[] = { - { - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, #ifdef CONFIG_SCHED_DEBUG +#ifndef CONFIG_SCHED_RIFS { .procname = "sched_min_granularity_ns", .data = &sysctl_sched_min_granularity, @@ -338,20 +334,7 @@ .extra2 = &one, }, #endif - { - .procname = "sched_rt_period_us", - .data = &sysctl_sched_rt_period, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_rt_handler, - }, - { - .procname = "sched_rt_runtime_us", - .data = &sysctl_sched_rt_runtime, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = sched_rt_handler, - }, +#endif #ifdef CONFIG_SCHED_AUTOGROUP { .procname = "sched_autogroup_enabled", |
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