RFC: [sparc32] atomic_t is 32 bits
From: | Keith M Wesolowski <wesolows@foobazco.org> | |
To: | sparclinux@vger.kernel.org | |
Subject: | RFC: [sparc32] atomic_t is 32 bits | |
Date: | Thu, 12 Feb 2004 21:20:29 -0800 |
This patch steals the atomic_t implementation from parisc. I've also left the existing implementation in as atomic24, primarily because it's tightly woven into the semaphores. Comments? # This is a BitKeeper generated patch for the following project: # Project Name: Linux kernel tree # This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas: # ChangeSet 1.1634 -> 1.1635 # include/asm-mips/atomic.h 1.6 -> 1.7 # arch/sparc/kernel/sparc_ksyms.c 1.23 -> 1.24 # include/asm-i386/atomic.h 1.5 -> 1.6 # arch/sparc/kernel/smp.c 1.10 -> 1.11 # arch/sparc/lib/atomic.S 1.2 -> 1.3 # include/asm-sparc/atomic.h 1.6 -> 1.7 # include/asm-generic/local.h 1.1 -> 1.2 # arch/sparc/kernel/semaphore.c 1.5 -> 1.6 # include/asm-x86_64/atomic.h 1.2 -> 1.3 # include/asm-sparc/semaphore.h 1.5 -> 1.6 # include/asm-sparc/processor.h 1.17 -> 1.18 # # The following is the BitKeeper ChangeSet Log # -------------------------------------------- # 04/02/12 wesolows@foobazco.org 1.1635 # atomic_t is now 32 bits # -------------------------------------------- # diff -Nru a/arch/sparc/kernel/semaphore.c b/arch/sparc/kernel/semaphore.c --- a/arch/sparc/kernel/semaphore.c Thu Feb 12 21:10:58 2004 +++ b/arch/sparc/kernel/semaphore.c Thu Feb 12 21:10:58 2004 @@ -61,7 +61,7 @@ * Add "everybody else" into it. They aren't * playing, because we own the spinlock. */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { + if (!atomic24_add_negative(sleepers - 1, &sem->count)) { sem->sleepers = 0; break; } @@ -101,7 +101,7 @@ if (signal_pending(current)) { retval = -EINTR; sem->sleepers = 0; - atomic_add(sleepers, &sem->count); + atomic24_add(sleepers, &sem->count); break; } @@ -111,7 +111,7 @@ * "-1" is because we're still hoping to get * the lock. */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { + if (!atomic24_add_negative(sleepers - 1, &sem->count)) { sem->sleepers = 0; break; } @@ -146,7 +146,7 @@ * Add "everybody else" and us into it. They aren't * playing, because we own the spinlock. */ - if (!atomic_add_negative(sleepers, &sem->count)) + if (!atomic24_add_negative(sleepers, &sem->count)) wake_up(&sem->wait); spin_unlock_irqrestore(&semaphore_lock, flags); diff -Nru a/arch/sparc/kernel/smp.c b/arch/sparc/kernel/smp.c --- a/arch/sparc/kernel/smp.c Thu Feb 12 21:10:58 2004 +++ b/arch/sparc/kernel/smp.c Thu Feb 12 21:10:58 2004 @@ -56,6 +56,9 @@ volatile int __cpu_number_map[NR_CPUS]; volatile int __cpu_logical_map[NR_CPUS]; cycles_t cacheflush_time = 0; /* XXX */ +spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] = { + [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED +}; /* The only guaranteed locking primitive available on all Sparc * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically diff -Nru a/arch/sparc/kernel/sparc_ksyms.c b/arch/sparc/kernel/sparc_ksyms.c --- a/arch/sparc/kernel/sparc_ksyms.c Thu Feb 12 21:10:58 2004 +++ b/arch/sparc/kernel/sparc_ksyms.c Thu Feb 12 21:10:58 2004 @@ -86,8 +86,8 @@ extern void dump_thread(struct pt_regs *, struct user *); /* Private functions with odd calling conventions. */ -extern void ___atomic_add(void); -extern void ___atomic_sub(void); +extern void ___atomic24_add(void); +extern void ___atomic24_sub(void); extern void ___set_bit(void); extern void ___clear_bit(void); extern void ___change_bit(void); @@ -147,8 +147,8 @@ EXPORT_SYMBOL(phys_base); /* Atomic operations. */ -EXPORT_SYMBOL(___atomic_add); -EXPORT_SYMBOL(___atomic_sub); +EXPORT_SYMBOL(___atomic24_add); +EXPORT_SYMBOL(___atomic24_sub); /* Bit operations. */ EXPORT_SYMBOL(___set_bit); diff -Nru a/arch/sparc/lib/atomic.S b/arch/sparc/lib/atomic.S --- a/arch/sparc/lib/atomic.S Thu Feb 12 21:10:58 2004 +++ b/arch/sparc/lib/atomic.S Thu Feb 12 21:10:58 2004 @@ -44,8 +44,8 @@ /* Read asm-sparc/atomic.h carefully to understand how this works for SMP. * Really, some things here for SMP are overly clever, go read the header. */ - .globl ___atomic_add -___atomic_add: + .globl ___atomic24_add +___atomic24_add: rd %psr, %g3 ! Keep the code small, old way was stupid nop; nop; nop; ! Let the bits set or %g3, PSR_PIL, %g7 ! Disable interrupts @@ -55,13 +55,13 @@ 1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. orcc %g7, 0x0, %g0 ! Did we get it? bne 1b ! Nope... - ld [%g1], %g7 ! Load locked atomic_t + ld [%g1], %g7 ! Load locked atomic24_t sra %g7, 8, %g7 ! Get signed 24-bit integer add %g7, %g2, %g2 ! Add in argument - sll %g2, 8, %g7 ! Transpose back to atomic_t + sll %g2, 8, %g7 ! Transpose back to atomic24_t st %g7, [%g1] ! Clever: This releases the lock as well. #else - ld [%g1], %g7 ! Load locked atomic_t + ld [%g1], %g7 ! Load locked atomic24_t add %g7, %g2, %g2 ! Add in argument st %g2, [%g1] ! Store it back #endif @@ -70,8 +70,8 @@ jmpl %o7, %g0 ! NOTE: not + 8, see callers in atomic.h mov %g4, %o7 ! Restore %o7 - .globl ___atomic_sub -___atomic_sub: + .globl ___atomic24_sub +___atomic24_sub: rd %psr, %g3 ! Keep the code small, old way was stupid nop; nop; nop; ! Let the bits set or %g3, PSR_PIL, %g7 ! Disable interrupts @@ -81,13 +81,13 @@ 1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. orcc %g7, 0x0, %g0 ! Did we get it? bne 1b ! Nope... - ld [%g1], %g7 ! Load locked atomic_t + ld [%g1], %g7 ! Load locked atomic24_t sra %g7, 8, %g7 ! Get signed 24-bit integer sub %g7, %g2, %g2 ! Subtract argument - sll %g2, 8, %g7 ! Transpose back to atomic_t + sll %g2, 8, %g7 ! Transpose back to atomic24_t st %g7, [%g1] ! Clever: This releases the lock as well #else - ld [%g1], %g7 ! Load locked atomic_t + ld [%g1], %g7 ! Load locked atomic24_t sub %g7, %g2, %g2 ! Subtract argument st %g2, [%g1] ! Store it back #endif diff -Nru a/include/asm-generic/local.h b/include/asm-generic/local.h --- a/include/asm-generic/local.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-generic/local.h Thu Feb 12 21:10:58 2004 @@ -9,7 +9,7 @@ /* An unsigned long type for operations which are atomic for a single * CPU. Usually used in combination with per-cpu variables. */ -#if BITS_PER_LONG == 32 && !defined(CONFIG_SPARC32) +#if BITS_PER_LONG == 32 /* Implement in terms of atomics. */ /* Don't use typedef: don't want them to be mixed with atomic_t's. */ diff -Nru a/include/asm-i386/atomic.h b/include/asm-i386/atomic.h --- a/include/asm-i386/atomic.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-i386/atomic.h Thu Feb 12 21:10:58 2004 @@ -27,8 +27,7 @@ * atomic_read - read atomic variable * @v: pointer of type atomic_t * - * Atomically reads the value of @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically reads the value of @v. */ #define atomic_read(v) ((v)->counter) @@ -37,8 +36,7 @@ * @v: pointer of type atomic_t * @i: required value * - * Atomically sets the value of @v to @i. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically sets the value of @v to @i. */ #define atomic_set(v,i) (((v)->counter) = (i)) @@ -47,8 +45,7 @@ * @i: integer value to add * @v: pointer of type atomic_t * - * Atomically adds @i to @v. Note that the guaranteed useful range - * of an atomic_t is only 24 bits. + * Atomically adds @i to @v. */ static __inline__ void atomic_add(int i, atomic_t *v) { @@ -63,8 +60,7 @@ * @i: integer value to subtract * @v: pointer of type atomic_t * - * Atomically subtracts @i from @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically subtracts @i from @v. */ static __inline__ void atomic_sub(int i, atomic_t *v) { @@ -81,8 +77,7 @@ * * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ static __inline__ int atomic_sub_and_test(int i, atomic_t *v) { @@ -99,8 +94,7 @@ * atomic_inc - increment atomic variable * @v: pointer of type atomic_t * - * Atomically increments @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically increments @v by 1. */ static __inline__ void atomic_inc(atomic_t *v) { @@ -114,8 +108,7 @@ * atomic_dec - decrement atomic variable * @v: pointer of type atomic_t * - * Atomically decrements @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically decrements @v by 1. */ static __inline__ void atomic_dec(atomic_t *v) { @@ -131,8 +124,7 @@ * * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other - * cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * cases. */ static __inline__ int atomic_dec_and_test(atomic_t *v) { @@ -151,8 +143,7 @@ * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ static __inline__ int atomic_inc_and_test(atomic_t *v) { @@ -172,8 +163,7 @@ * * Atomically adds @i to @v and returns true * if the result is negative, or false when - * result is greater than or equal to zero. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * result is greater than or equal to zero. */ static __inline__ int atomic_add_negative(int i, atomic_t *v) { diff -Nru a/include/asm-mips/atomic.h b/include/asm-mips/atomic.h --- a/include/asm-mips/atomic.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-mips/atomic.h Thu Feb 12 21:10:58 2004 @@ -29,8 +29,7 @@ * atomic_read - read atomic variable * @v: pointer of type atomic_t * - * Atomically reads the value of @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically reads the value of @v. */ #define atomic_read(v) ((v)->counter) @@ -46,8 +45,7 @@ * @v: pointer of type atomic_t * @i: required value * - * Atomically sets the value of @v to @i. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically sets the value of @v to @i. */ #define atomic_set(v,i) ((v)->counter = (i)) @@ -68,8 +66,7 @@ * @i: integer value to add * @v: pointer of type atomic_t * - * Atomically adds @i to @v. Note that the guaranteed useful range - * of an atomic_t is only 24 bits. + * Atomically adds @i to @v. */ static __inline__ void atomic_add(int i, atomic_t * v) { @@ -85,8 +82,7 @@ * @i: integer value to subtract * @v: pointer of type atomic_t * - * Atomically subtracts @i from @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically subtracts @i from @v. */ static __inline__ void atomic_sub(int i, atomic_t * v) { @@ -137,8 +133,7 @@ * @i: integer value to add * @v: pointer of type atomic_t * - * Atomically adds @i to @v. Note that the guaranteed useful range - * of an atomic_t is only 24 bits. + * Atomically adds @i to @v. */ static __inline__ void atomic_add(int i, atomic_t * v) { @@ -158,8 +153,7 @@ * @i: integer value to subtract * @v: pointer of type atomic_t * - * Atomically subtracts @i from @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically subtracts @i from @v. */ static __inline__ void atomic_sub(int i, atomic_t * v) { @@ -390,8 +384,7 @@ * * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) @@ -412,8 +405,7 @@ * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) @@ -433,8 +425,7 @@ * * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other - * cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * cases. */ #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) @@ -452,8 +443,7 @@ * atomic_inc - increment atomic variable * @v: pointer of type atomic_t * - * Atomically increments @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically increments @v by 1. */ #define atomic_inc(v) atomic_add(1,(v)) @@ -469,8 +459,7 @@ * atomic_dec - decrement and test * @v: pointer of type atomic_t * - * Atomically decrements @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically decrements @v by 1. */ #define atomic_dec(v) atomic_sub(1,(v)) @@ -489,8 +478,7 @@ * * Atomically adds @i to @v and returns true * if the result is negative, or false when - * result is greater than or equal to zero. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * result is greater than or equal to zero. */ #define atomic_add_negative(i,v) (atomic_add_return(i, (v)) < 0) diff -Nru a/include/asm-sparc/atomic.h b/include/asm-sparc/atomic.h --- a/include/asm-sparc/atomic.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-sparc/atomic.h Thu Feb 12 21:10:58 2004 @@ -2,21 +2,82 @@ * * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com.au) + * + * Additions by Keith M Wesolowski (wesolows@foobazco.org) based + * on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>. */ #ifndef __ARCH_SPARC_ATOMIC__ #define __ARCH_SPARC_ATOMIC__ #include <linux/config.h> +#include <linux/spinlock.h> typedef struct { volatile int counter; } atomic_t; #ifdef __KERNEL__ -#ifndef CONFIG_SMP + +#ifdef CONFIG_SMP + +#define ATOMIC_HASH_SIZE 4 +#define ATOMIC_HASH(a) (&__atomic_hash[(((unsigned long)a)>>8) & (ATOMIC_HASH_SIZE-1)]) +extern spinlock_t __atomic_hash[ATOMIC_HASH_SIZE]; + +#else /* SMP */ + +#define ATOMIC_HASH_SIZE 1 +#define ATOMIC_HASH(a) 0 + +#endif /* SMP */ + +static inline int __atomic_add_return(int i, atomic_t *v) +{ + int ret; + unsigned long flags; + spin_lock_irqsave(ATOMIC_HASH(v), flags); + + ret = (v->counter += i); + + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); + return ret; +} + +static inline void atomic_set(atomic_t *v, int i) +{ + unsigned long flags; + spin_lock_irqsave(ATOMIC_HASH(v), flags); + + v->counter = i; + + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); +} #define ATOMIC_INIT(i) { (i) } + #define atomic_read(v) ((v)->counter) -#define atomic_set(v, i) (((v)->counter) = i) + +#define atomic_add(i, v) ((void)__atomic_add_return( (int)(i), (v))) +#define atomic_sub(i, v) ((void)__atomic_add_return(-(int)(i), (v))) +#define atomic_inc(v) ((void)__atomic_add_return( 1, (v))) +#define atomic_dec(v) ((void)__atomic_add_return( -1, (v))) + +#define atomic_add_return(i, v) (__atomic_add_return( (int)(i), (v))) +#define atomic_sub_return(i, v) (__atomic_add_return(-(int)(i), (v))) +#define atomic_inc_return(v) (__atomic_add_return( 1, (v))) +#define atomic_dec_return(v) (__atomic_add_return( -1, (v))) + +#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0) + +/* This is the old 24-bit implementation. It's still used internally + * by some sparc-specific code, notably the semaphore implementation. + */ +typedef struct { volatile int counter; } atomic24_t; + +#ifndef CONFIG_SMP + +#define ATOMIC24_INIT(i) { (i) } +#define atomic24_read(v) ((v)->counter) +#define atomic24_set(v, i) (((v)->counter) = i) #else /* We do the bulk of the actual work out of line in two common @@ -33,9 +94,9 @@ * 31 8 7 0 */ -#define ATOMIC_INIT(i) { ((i) << 8) } +#define ATOMIC24_INIT(i) { ((i) << 8) } -static __inline__ int atomic_read(const atomic_t *v) +static inline int atomic24_read(const atomic24_t *v) { int ret = v->counter; @@ -45,10 +106,10 @@ return ret >> 8; } -#define atomic_set(v, i) (((v)->counter) = ((i) << 8)) +#define atomic24_set(v, i) (((v)->counter) = ((i) << 8)) #endif -static inline int __atomic_add(int i, atomic_t *v) +static inline int __atomic24_add(int i, atomic24_t *v) { register volatile int *ptr asm("g1"); register int increment asm("g2"); @@ -61,7 +122,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_add\n\t" + "call ___atomic24_add\n\t" " add %%o7, 8, %%o7\n" : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3) : "0" (increment), "r" (ptr) @@ -70,7 +131,7 @@ return increment; } -static inline int __atomic_sub(int i, atomic_t *v) +static inline int __atomic24_sub(int i, atomic24_t *v) { register volatile int *ptr asm("g1"); register int increment asm("g2"); @@ -83,7 +144,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_sub\n\t" + "call ___atomic24_sub\n\t" " add %%o7, 8, %%o7\n" : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3) : "0" (increment), "r" (ptr) @@ -92,19 +153,19 @@ return increment; } -#define atomic_add(i, v) ((void)__atomic_add((i), (v))) -#define atomic_sub(i, v) ((void)__atomic_sub((i), (v))) +#define atomic24_add(i, v) ((void)__atomic24_add((i), (v))) +#define atomic24_sub(i, v) ((void)__atomic24_sub((i), (v))) -#define atomic_dec_return(v) __atomic_sub(1, (v)) -#define atomic_inc_return(v) __atomic_add(1, (v)) +#define atomic24_dec_return(v) __atomic24_sub(1, (v)) +#define atomic24_inc_return(v) __atomic24_add(1, (v)) -#define atomic_sub_and_test(i, v) (__atomic_sub((i), (v)) == 0) -#define atomic_dec_and_test(v) (__atomic_sub(1, (v)) == 0) +#define atomic24_sub_and_test(i, v) (__atomic24_sub((i), (v)) == 0) +#define atomic24_dec_and_test(v) (__atomic24_sub(1, (v)) == 0) -#define atomic_inc(v) ((void)__atomic_add(1, (v))) -#define atomic_dec(v) ((void)__atomic_sub(1, (v))) +#define atomic24_inc(v) ((void)__atomic24_add(1, (v))) +#define atomic24_dec(v) ((void)__atomic24_sub(1, (v))) -#define atomic_add_negative(i, v) (__atomic_add((i), (v)) < 0) +#define atomic24_add_negative(i, v) (__atomic24_add((i), (v)) < 0) /* Atomic operations are already serializing */ #define smp_mb__before_atomic_dec() barrier() diff -Nru a/include/asm-sparc/processor.h b/include/asm-sparc/processor.h --- a/include/asm-sparc/processor.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-sparc/processor.h Thu Feb 12 21:10:58 2004 @@ -22,7 +22,6 @@ #include <asm/segment.h> #include <asm/btfixup.h> #include <asm/page.h> -#include <asm/atomic.h> /* * Bus types diff -Nru a/include/asm-sparc/semaphore.h b/include/asm-sparc/semaphore.h --- a/include/asm-sparc/semaphore.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-sparc/semaphore.h Thu Feb 12 21:10:58 2004 @@ -10,7 +10,7 @@ #include <linux/rwsem.h> struct semaphore { - atomic_t count; + atomic24_t count; int sleepers; wait_queue_head_t wait; #if WAITQUEUE_DEBUG @@ -40,7 +40,7 @@ static inline void sema_init (struct semaphore *sem, int val) { - atomic_set(&sem->count, val); + atomic24_set(&sem->count, val); sem->sleepers = 0; init_waitqueue_head(&sem->wait); #if WAITQUEUE_DEBUG @@ -78,7 +78,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_sub\n\t" + "call ___atomic24_sub\n\t" " add %%o7, 8, %%o7\n\t" "tst %%g2\n\t" "bl 2f\n\t" @@ -115,7 +115,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_sub\n\t" + "call ___atomic24_sub\n\t" " add %%o7, 8, %%o7\n\t" "tst %%g2\n\t" "bl 2f\n\t" @@ -154,7 +154,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_sub\n\t" + "call ___atomic24_sub\n\t" " add %%o7, 8, %%o7\n\t" "tst %%g2\n\t" "bl 2f\n\t" @@ -193,7 +193,7 @@ __asm__ __volatile__( "mov %%o7, %%g4\n\t" - "call ___atomic_add\n\t" + "call ___atomic24_add\n\t" " add %%o7, 8, %%o7\n\t" "tst %%g2\n\t" "ble 2f\n\t" diff -Nru a/include/asm-x86_64/atomic.h b/include/asm-x86_64/atomic.h --- a/include/asm-x86_64/atomic.h Thu Feb 12 21:10:58 2004 +++ b/include/asm-x86_64/atomic.h Thu Feb 12 21:10:58 2004 @@ -29,8 +29,7 @@ * atomic_read - read atomic variable * @v: pointer of type atomic_t * - * Atomically reads the value of @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically reads the value of @v. */ #define atomic_read(v) ((v)->counter) @@ -39,8 +38,7 @@ * @v: pointer of type atomic_t * @i: required value * - * Atomically sets the value of @v to @i. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically sets the value of @v to @i. */ #define atomic_set(v,i) (((v)->counter) = (i)) @@ -49,8 +47,7 @@ * @i: integer value to add * @v: pointer of type atomic_t * - * Atomically adds @i to @v. Note that the guaranteed useful range - * of an atomic_t is only 24 bits. + * Atomically adds @i to @v. */ static __inline__ void atomic_add(int i, atomic_t *v) { @@ -65,8 +62,7 @@ * @i: integer value to subtract * @v: pointer of type atomic_t * - * Atomically subtracts @i from @v. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically subtracts @i from @v. */ static __inline__ void atomic_sub(int i, atomic_t *v) { @@ -83,8 +79,7 @@ * * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ static __inline__ int atomic_sub_and_test(int i, atomic_t *v) { @@ -101,8 +96,7 @@ * atomic_inc - increment atomic variable * @v: pointer of type atomic_t * - * Atomically increments @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically increments @v by 1. */ static __inline__ void atomic_inc(atomic_t *v) { @@ -116,8 +110,7 @@ * atomic_dec - decrement atomic variable * @v: pointer of type atomic_t * - * Atomically decrements @v by 1. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * Atomically decrements @v by 1. */ static __inline__ void atomic_dec(atomic_t *v) { @@ -133,8 +126,7 @@ * * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other - * cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * cases. */ static __inline__ int atomic_dec_and_test(atomic_t *v) { @@ -153,8 +145,7 @@ * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all - * other cases. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * other cases. */ static __inline__ int atomic_inc_and_test(atomic_t *v) { @@ -174,8 +165,7 @@ * * Atomically adds @i to @v and returns true * if the result is negative, or false when - * result is greater than or equal to zero. Note that the guaranteed - * useful range of an atomic_t is only 24 bits. + * result is greater than or equal to zero. */ static __inline__ int atomic_add_negative(int i, atomic_t *v) { -- Keith M Wesolowski - To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html