linux/kernel
Paul Jackson 029190c515 cpuset sched_load_balance flag
Add a new per-cpuset flag called 'sched_load_balance'.

When enabled in a cpuset (the default value) it tells the kernel scheduler
that the scheduler should provide the normal load balancing on the CPUs in
that cpuset, sometimes moving tasks from one CPU to a second CPU if the
second CPU is less loaded and if that task is allowed to run there.

When disabled (write "0" to the file) then it tells the kernel scheduler
that load balancing is not required for the CPUs in that cpuset.

Now even if this flag is disabled for some cpuset, the kernel may still
have to load balance some or all the CPUs in that cpuset, if some
overlapping cpuset has its sched_load_balance flag enabled.

If there are some CPUs that are not in any cpuset whose sched_load_balance
flag is enabled, the kernel scheduler will not load balance tasks to those
CPUs.

Moreover the kernel will partition the 'sched domains' (non-overlapping
sets of CPUs over which load balancing is attempted) into the finest
granularity partition that it can find, while still keeping any two CPUs
that are in the same shed_load_balance enabled cpuset in the same element
of the partition.

This serves two purposes:
 1) It provides a mechanism for real time isolation of some CPUs, and
 2) it can be used to improve performance on systems with many CPUs
    by supporting configurations in which load balancing is not done
    across all CPUs at once, but rather only done in several smaller
    disjoint sets of CPUs.

This mechanism replaces the earlier overloading of the per-cpuset
flag 'cpu_exclusive', which overloading was removed in an earlier
patch: cpuset-remove-sched-domain-hooks-from-cpusets

See further the Documentation and comments in the code itself.

[akpm@linux-foundation.org: don't be weird]
Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:41 -07:00
..
irq Compile handle_percpu_irq even for uniprocessor kernels 2007-10-17 08:43:00 -07:00
power Hibernation: Enter platform hibernation state in a consistent way 2007-10-18 14:37:20 -07:00
time kernel/time/clocksource.c: Use list_for_each_entry instead of list_for_each 2007-10-19 11:53:38 -07:00
.gitignore gitignore: ignore more generated files 2006-01-03 11:35:26 +01:00
Kconfig.hz [PATCH] HZ: 300Hz support 2006-12-07 08:39:36 -08:00
Kconfig.preempt Move PREEMPT_NOTIFIERS into an always-included Kconfig 2007-10-17 08:42:55 -07:00
Makefile cgroups: implement namespace tracking subsystem 2007-10-19 11:53:37 -07:00
acct.c whitespace fixes: process accounting 2007-10-18 14:37:24 -07:00
audit.c whitespace fixes: system auditing 2007-10-18 14:37:25 -07:00
audit.h Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
auditfilter.c whitespace fixes: audit filtering 2007-10-18 14:37:24 -07:00
auditsc.c whitespace fixes: syscall auditing 2007-10-18 14:37:25 -07:00
capability.c Uninline find_pid etc set of functions 2007-10-19 11:53:41 -07:00
cgroup.c Add cgroupstats 2007-10-19 11:53:36 -07:00
cgroup_debug.c Task Control Groups: simple task cgroup debug info subsystem 2007-10-19 11:53:36 -07:00
compat.c Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt 2007-10-18 15:12:41 -07:00
configs.c use simple_read_from_buffer in kernel/ 2007-05-09 12:30:49 -07:00
cpu.c cpu hotplug: cpu: deliver CPU_UP_CANCELED only to NOTIFY_OKed callbacks with CPU_UP_PREPARE 2007-10-18 14:37:21 -07:00
cpu_acct.c Task Control Groups: example CPU accounting subsystem 2007-10-19 11:53:36 -07:00
cpuset.c cpuset sched_load_balance flag 2007-10-19 11:53:41 -07:00
delayacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
dma.c whitespace fixes: DMA channel allocator 2007-10-18 14:37:24 -07:00
exec_domain.c whitespace fixes: execution domains 2007-10-18 14:37:26 -07:00
exit.c pid namespaces: changes to show virtual ids to user 2007-10-19 11:53:40 -07:00
extable.c [PATCH] symbol_put_addr() locks kernel 2006-05-15 11:20:55 -07:00
fork.c pid namespaces: changes to show virtual ids to user 2007-10-19 11:53:40 -07:00
futex.c Uninline find_task_by_xxx set of functions 2007-10-19 11:53:40 -07:00
futex_compat.c Uninline find_task_by_xxx set of functions 2007-10-19 11:53:40 -07:00
hrtimer.c hrtimer: Rework hrtimer_nanosleep to make sys_compat_nanosleep easier 2007-10-18 22:54:18 +02:00
itimer.c whitespace fixes: interval timers 2007-10-18 14:37:26 -07:00
kallsyms.c kallsyms: make KSYM_NAME_LEN include space for trailing '\0' 2007-07-17 10:23:03 -07:00
kexec.c pid namespaces: define is_global_init() and is_container_init() 2007-10-19 11:53:37 -07:00
kfifo.c is_power_of_2: kernel/kfifo.c 2007-07-16 09:05:50 -07:00
kmod.c Restore call_usermodehelper_pipe() behaviour 2007-09-11 17:21:20 -07:00
kprobes.c kprobes: support kretprobe blacklist 2007-10-16 09:43:10 -07:00
ksysfs.c add-vmcore: cleanup the coding style according to Andrew's comments 2007-10-17 08:42:54 -07:00
kthread.c kthread: silence bogus section mismatch warning 2007-07-31 15:39:42 -07:00
latency.c [PATCH] severing module.h->sched.h 2006-12-04 02:00:22 -05:00
lockdep.c workqueue: debug flushing deadlocks with lockdep 2007-10-19 11:53:38 -07:00
lockdep_internals.h [PATCH] lockdep: more chains 2006-12-07 08:39:43 -08:00
lockdep_proc.c lockdep: Avoid /proc/lockdep & lock_stat infinite output 2007-10-11 22:11:11 +02:00
module.c whitespace fixes: module loading 2007-10-18 14:37:25 -07:00
mutex-debug.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
mutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
mutex.c lockdep: fixup mutex annotations 2007-10-11 22:11:12 +02:00
mutex.h [PATCH] lockdep: prove mutex locking correctness 2006-07-03 15:27:04 -07:00
notifier.c Add kernel/notifier.c 2007-10-19 11:53:34 -07:00
ns_cgroup.c cgroups: implement namespace tracking subsystem 2007-10-19 11:53:37 -07:00
nsproxy.c pid namespaces: allow cloning of new namespace 2007-10-19 11:53:39 -07:00
panic.c whitespace fixes: panic handling 2007-10-18 14:37:25 -07:00
params.c param_sysfs_builtin memchr argument fix 2007-10-18 14:37:21 -07:00
pid.c Uninline the task_xid_nr_ns() calls 2007-10-19 11:53:41 -07:00
posix-cpu-timers.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
posix-timers.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
printk.c serial: turn serial console suspend a boot rather than compile time option 2007-10-18 14:37:19 -07:00
profile.c make kernel/profile.c:time_hook static 2007-10-17 08:42:55 -07:00
ptrace.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
rcupdate.c Clean up duplicate includes in kernel/ 2007-10-17 08:42:48 -07:00
rcutorture.c Make rcutorture RNG use temporal entropy 2007-10-17 08:42:53 -07:00
relay.c whitespace fixes: relayfs 2007-10-18 14:37:24 -07:00
resource.c memory unplug: memory hotplug cleanup 2007-10-16 09:43:01 -07:00
rtmutex-debug.c kernel/rtmutex-debug.c: cleanups 2007-10-17 08:42:50 -07:00
rtmutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rtmutex-tester.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
rtmutex.c FUTEX: Tidy up the code 2007-07-16 09:05:49 -07:00
rtmutex.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rtmutex_common.h FUTEX: Tidy up the code 2007-07-16 09:05:49 -07:00
rwsem.c lockstat: hook into spinlock_t, rwlock_t, rwsem and mutex 2007-07-19 10:04:49 -07:00
sched.c cpuset sched_load_balance flag 2007-10-19 11:53:41 -07:00
sched_debug.c sched: reduce schedstat variable overhead a bit 2007-10-18 21:32:56 +02:00
sched_fair.c sched: fix new task startup crash 2007-10-17 16:55:11 +02:00
sched_idletask.c sched: mark scheduling classes as const 2007-10-15 17:00:12 +02:00
sched_rt.c sched: tidy up SCHED_RR 2007-10-15 17:00:13 +02:00
sched_stats.h sched: reduce schedstat variable overhead a bit 2007-10-18 21:32:56 +02:00
seccomp.c make seccomp zerocost in schedule 2007-07-16 09:05:50 -07:00
signal.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
softirq.c [KERNEL]: Unexport raise_softirq_irqoff 2007-10-10 16:49:18 -07:00
softlockup.c softlockup: add a /proc tuning parameter 2007-10-17 08:42:47 -07:00
spinlock.c lockstat: hook into spinlock_t, rwlock_t, rwsem and mutex 2007-07-19 10:04:49 -07:00
srcu.c [PATCH] SRCU: report out-of-memory errors 2006-10-04 07:55:30 -07:00
stacktrace.c [PATCH] lockdep: stacktrace subsystem, core 2006-07-03 15:27:02 -07:00
stop_machine.c Fix stop_machine_run problem with naughty real time process 2007-07-16 09:05:41 -07:00
sys.c Uninline find_task_by_xxx set of functions 2007-10-19 11:53:40 -07:00
sys_ni.c kernel/sys_ni.c: add dummy sys_ni_syscall() prototype 2007-10-17 08:42:55 -07:00
sysctl.c pid namespaces: changes to show virtual ids to user 2007-10-19 11:53:40 -07:00
sysctl_check.c V3 file capabilities: alter behavior of cap_setpcap 2007-10-18 14:37:24 -07:00
taskstats.c Add cgroupstats 2007-10-19 11:53:36 -07:00
time.c whitespace fixes: time syscalls 2007-10-18 14:37:24 -07:00
timer.c pid namespaces: changes to show virtual ids to user 2007-10-19 11:53:40 -07:00
tsacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
uid16.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
user.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched 2007-10-17 09:11:18 -07:00
user_namespace.c Fix user namespace exiting OOPs 2007-09-19 11:24:18 -07:00
utsname.c Fix UTS corruption during clone(CLONE_NEWUTS) 2007-09-19 11:24:17 -07:00
utsname_sysctl.c remove CONFIG_UTS_NS and CONFIG_IPC_NS 2007-07-16 09:05:47 -07:00
wait.c Fix occurrences of "the the " 2007-05-09 08:57:56 +02:00
workqueue.c workqueue: debug flushing deadlocks with lockdep 2007-10-19 11:53:38 -07:00