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cpumask: reduce stack pressure from local/passed cpumask variables
| From: | Mike Travis <travis@sgi.com> | |
| To: | Andrew Morton <akpm@linux-foundation.org> | |
| Subject: | [PATCH 00/12] cpumask: reduce stack pressure from local/passed cpumask variables | |
| Date: | Mon, 24 Mar 2008 19:31:20 -0700 | |
| Message-ID: | <20080325023120.859257000@polaris-admin.engr.sgi.com> | |
| Cc: | linux-mm@kvack.org, linux-kernel@vger.kernel.org | |
| Archive-link: | Article, Thread |
Modify usage of cpumask_t variables to use pointers as much as possible.
Changes are:
* Use a per_cpu variable for cpumask_of_cpu when large NR_CPUS count
is present. This removes 25552 bytes of stack usage (see chart
below), as well as reduces the code generated for each usage.
* Modify set_cpus_allowed to pass a pointer to the "newly allowed"
cpumask. This removes 10784 bytes of stack usage but is an
ABI change.
* Add node_to_cpumask_ptr that returns pointer to cpumask for the
specified node. This removes 9824 bytes of stack usage.
* Modify build_sched_domains and related sub-functions to pass
pointers to cpumask temp variables. This consolidates stack
space that was spread over various functions.
* Remove large array from numa_initmem_init() [-8248 bytes].
* Optimize usages of {CPU,NODE}_MASK_{NONE,ALL} [-9408 bytes].
* Various other changes to reduce stacksize and silence checkpatch
warnings [-7672 bytes].
Based on linux-2.6.25-rc5-mm1
Cc: Anton Blanchard <anton@samba.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Cliff Wickman <cpw@sgi.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: William L. Irwin <wli@holomorphy.com>
Signed-off-by: Mike Travis <travis@sgi.com>
---
Summaries:
1 - Memory Usages Changes
2 - Build & Test Results
--- ---------------------------------------------------------
* Memory Usages Changes
Patch list summary of various memory usage changes using the akpm2
config file with NR_CPUS=4096 and MAX_NUMNODES=512.
====== Data (-l 500)
1 - initial
2 - cpumask_of_cpu
8 - sched_domain
13 - CPU_NODE_MASK
.1. .2. .8. .13. ..final..
3553 . -1146 +296 2703 -23% build_sched_domains(.text)
533 -533 . . . -100% hpet_enable(.init.text)
512 . . -512 . -100% C(.rodata)
501 . . -501 . -100% acpi_ex_get_name_string(.text)
0 +512 . . 512 . per_cpu__cpu_mask(.data.percpu)
0 . . +512 512 . cpu_mask_all(.data)
5099 -21 -1146 -205 3727 -26% Totals
====== Text/Data ()
1 - initial
2 - cpumask_of_cpu
3 - set_cpus_allowed
6 - numa_initmem_init
13 - CPU_NODE_MASK
.1. .2. .3. .6. .13. ..final..
3375104 . -2048 . . 3373056 <1% TextSize
1658880 . -2048 . -4096 1652736 <1% DataSize
1142784 . . +8192 . 1150976 <1% InitSize
47104 +2048 . . . 49152 +4% PerCPU
10399744 . -4096 . +4096 10399744 . OtherSize
16623616 +2048 -8192 +8192 . 16625664 +0% Totals
====== PerCPU ()
1 - initial
2 - cpumask_of_cpu
.1. .2. ..final..
18432 -2048 16384 -11% kstat
2048 -2048 . -100% vmstat_work
2048 -2048 . -100% rt_cache_stat
0 +2048 2048 . lru_add_active_pvecs
0 +2048 2048 . cpuidle_devices
0 +2048 2048 . cpu_info
0 +2048 2048 . cpu_mask
22528 +2048 24576 +9% Totals
====== Stack (-l 500)
1 - initial
2 - cpumask_of_cpu
3 - set_cpus_allowed
4 - cpumask_affinity
6 - numa_initmem_init
7 - node_to_cpumask_ptr
8 - sched_domain
9 - kern_sched
11 - build_sched_domains
12 - cpu_coregroup_map
13 - CPU_NODE_MASK
.1. .2. .3. .4. .6. .7. .8. .9. .11. .12. .13. ..final..
11080 . . . . -512 -6352 . -976 +16 -512 2744 -75%
build_sched_domains
8248 . . . -8248 . . . . . . . -100%
numa_initmem_init
3672 -1024 -496 . . . . . . . . 2152 -41%
centrino_target
3176 . . . . -2512 . . . . . 664 -79%
sched_domain_node_span
3096 -1536 -512 . . . . . . . . 1048 -66%
acpi_processor_set_throttling
2600 -1536 . . . . . . . . -512 552 -78%
powernowk8_cpu_init
2120 -1024 -512 . . . . . . . . 584 -72%
cache_add_dev
2104 -1008 . . . . . . . . -512 584 -72%
powernowk8_target
2088 . -512 . . . . . . . -512 1064 -49% _cpu_down
2072 -512 . . . . . . . . . 1560 -24%
tick_notify
2064 -1024 . . . . . . . . -504 536 -74%
check_supported_cpu
2056 . -1544 +520 . . . . . . . 1032 -49%
sched_setaffinity
2056 -1024 -512 . . . . . . . . 520 -74%
get_cur_freq
2056 . -512 -1032 . . . . . . -512 . -100%
affinity_set
2056 -1024 -520 . . . . . . . . 512 -75%
acpi_processor_get_throttling
2056 -1024 -512 . . . . . . . . 520 -74%
acpi_processor_ffh_cstate_probe
2048 -1016 -520 . . . . . . . . 512 -75%
powernowk8_get
1784 -1024 . . . . . . . . . 760 -57%
cpufreq_add_dev
1768 . -512 . . -1024 . . . . . 232 -86% kswapd
1608 -1504 . . . . . . . . . 104 -93%
disable_smp
1592 . . . . -1592 . . . . . . -100%
do_tune_cpucache
1576 . . . . . . -480 . . -1096 . -100%
init_sched_build_groups
1560 -1024 -536 . . . . . . . . . -100%
native_machine_shutdown
1552 . -512 . . . . . . . -1040 . -100% kthreadd
1544 -1024 -520 . . . . . . . . . -100%
stopmachine
1544 -1008 . . . . . . . . . 536 -65% alloc_ldt
1536 -1024 . . . . . . . . . 512 -66%
smp_send_reschedule
1536 -1024 . . . . . . . . . 512 -66%
smp_call_function_single
1536 . -504 . . -512 . . . . . 520 -66%
pci_device_probe
1176 . . . . . . -512 . . . 664 -43%
thread_return
1176 . . . . . . -512 . . . 664 -43% schedule
1144 . . +512 . . . . . . -512 1144 .
threshold_create_device
1144 . . . . . . -512 . . . 632 -44%
run_rebalance_domains
1144 . . . . -1024 . . . . . 120 -89%
__build_all_zonelists
1080 . -520 . . . . . . . . 560 -48% pdflush
1080 . -512 . . . . . . . -568 . -100%
kernel_init
1064 . . . . -1064 . . . . . . -100%
cpuup_canceled
1064 . . . . -1064 . . . . . . -100%
cpuup_callback
1032 -1032 . . . . . . . . . . -100%
setup_pit_timer
1032 . . . . . . . . . -520 512 -50%
physflat_vector_allocation_domain
1032 -1032 . . . . . . . . . . -100%
init_workqueues
1032 -1032 . . . . . . . . . . -100% init_idle
1032 . . . . . . . . . -512 520 -49%
destroy_irq
1024 . . -512 . . . . . . . 512 -50%
sys_sched_setaffinity
1024 -1024 . . . . . . . . . . -100%
setup_APIC_timer
1024 . -504 . . . . . . . . 520 -49%
sched_init_smp
1024 -1024 . . . . . . . . . . -100%
kthread_bind
1024 -1024 . . . . . . . . . . -100%
hpet_enable
1024 . . -512 . . . . . . . 512 -50%
compat_sys_sched_setaffinity
1024 . . . . . . . . . -512 512 -50%
__percpu_populate_mask
1024 . -512 . . . . . . . -512 . -100%
____call_usermodehelper
568 . . . . . . -568 . . . . -100%
cpu_attach_domain
552 . . . . . . . . . -552 . -100%
migration_call
520 . . . . -520 . . . . . . -100%
node_read_cpumap
520 . . . . . . . . . -520 . -100%
dynamic_irq_init
520 . . . . . . -8 . -512 . . -100%
cpu_to_phys_group
520 . . . . . . -520 . . . . -100%
cpu_to_core_group
0 . . . . . +760 . . . . 760 .
sd_init_SIBLING
0 . . . . . +760 . . . . 760 .
sd_init_NODE
0 . . . . . +752 . . . . 752 . sd_init_MC
0 . . . . . +752 . . . . 752 .
sd_init_CPU
0 . . . . . +752 . . . . 752 .
sd_init_ALLNODES
0 . . . . . . +512 . . . 512 .
detach_destroy_domains
100408 -25552 -10784 -1024 -8248 -9824 -2576 -2600 -976 -496 -9408 28920 -71% Totals
--- ---------------------------------------------------------
* Build & Test Results
Built/tested:
nosmp
nonuma
defconfig (NR_CPUS/MAX_NUMANODES: 32/64 and 4096/512)
akpm2 config (NR_CPUS/MAX_NUMANODES: 255/64 and 4096/512)
Built no errors:
allyesconfig
allnoconfig
allmodconfig
current-x86_64-default
current-ia64-sn2
current-ia64-default
current-ia64-nosmp
current-ia64-zx1
current-s390-default
current-arm-default
current-sparc-default
current-sparc64-default
current-sparc64-smp
current-ppc-pmac32
Not Built (previous errors):
current-x86_64-single
drivers/built-in.o: In function `sas_request_addr':
(.text+0x814bd): undefined reference to `request_firmware'
drivers/built-in.o: In function `sas_request_addr':
(.text+0x81556): undefined reference to `release_firmware'
current-x86_64-8psmp
drivers/built-in.o: In function `sas_request_addr':
(.text+0x814bd): undefined reference to `request_firmware'
drivers/built-in.o: In function `sas_request_addr':
(.text+0x81556): undefined reference to `release_firmware'
current-x86_64-debug
sas_scsi_host.c:1091: undefined reference to `request_firmware'
sas_scsi_host.c:1103: undefined reference to `release_firmware'
current-x86_64-numa
drivers/built-in.o: In function `sas_request_addr':
(.text+0x8540d): undefined reference to `request_firmware'
drivers/built-in.o: In function `sas_request_addr':
(.text+0x854a6): undefined reference to `release_firmware'
current-i386-single
drivers/built-in.o: In function `sas_request_addr':
(.text+0x7617a): undefined reference to `request_firmware'
drivers/built-in.o: In function `sas_request_addr':
(.text+0x76208): undefined reference to `release_firmware'
current-i386-smp
drivers/built-in.o: In function `sas_request_addr':
(.text+0x7985a): undefined reference to `request_firmware'
drivers/built-in.o: In function `sas_request_addr':
(.text+0x798e8): undefined reference to `release_firmware'
current-ppc-smp
WRAP arch/powerpc/boot/uImage
ln: accessing `arch/powerpc/boot/uImage': No such file or directory
(Note: build with patches applied did not change errors.)
--- ---------------------------------------------------------
--