Peter Zijlstra 3f5087a2ba sched: fix share (re)distribution ... fix __aggregate_redistribute_shares() related lockup reported by David S. Miller. The problem this code tries to solve is 'accurately' calculating the 'fair' share of the group weight for each cpu. The current code falls back to a global group rebalance in case the sched_domain's span it looks at has no shares, but does have tasks. The reason it gets stuck here, is because its inherently racy - if someone steals the last task after we compute the agg->rq_weight, but before we rebalance, we'll never get out of the loop. We could of course go fix that, but while looking at this issue I found that this 'fallback' wasn't nearly as rare as I'd hoped it to be. In fact its quite common - and given it walks the whole machine, thats very bad. The new approach is simple (why didn't I think of it before?), we set the aggregate shares to the full task group weight, and each larger sched domain that encounters an aggregate shares larger than the weight, clips it (it already re-distributes anyway). This nicely converges to the desired global picture where the sum of all shares equals the task group weight. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>		2008-04-25 00:25:08 +02:00
..
irq	cpumask: Cleanup more uses of CPU_MASK and NODE_MASK	2008-04-19 19:44:58 +02:00
power	Merge branches 'release' and 'doc' into release	2008-03-13 01:59:53 -04:00
time	softlockup: fix NOHZ wakeup	2008-04-25 00:25:08 +02:00
.gitignore	Update kernel/.gitignore with new auto-generated files	2008-02-09 23:27:01 -08:00
acct.c	bsd_acct: using task_struct->tgid is not right in pid-namespaces	2008-03-24 19:22:20 -07:00
audit_tree.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
audit.c	Audit: internally use the new LSM audit hooks	2008-04-19 09:52:37 +10:00
audit.h	SELinux: use new audit hooks, remove redundant exports	2008-04-19 09:53:46 +10:00
auditfilter.c	Audit: Final renamings and cleanup	2008-04-19 09:59:43 +10:00
auditsc.c	Audit: Final renamings and cleanup	2008-04-19 09:59:43 +10:00
backtracetest.c
capability.c
cgroup_debug.c
cgroup.c	cgroup: fix a race condition in manipulating tsk->cg_list	2008-04-18 08:17:57 -07:00
compat.c	generic: reduce stack pressure in sched_affinity	2008-04-19 19:44:59 +02:00
configs.c
cpu.c	generic: use new set_cpus_allowed_ptr function	2008-04-19 19:44:58 +02:00
cpuset.c	sched, cpuset: customize sched domains, core	2008-04-19 19:45:00 +02:00
delayacct.c
dma.c
exec_domain.c
exit.c	[PATCH] get rid of __exit_files(), __exit_fs() and __put_fs_struct()	2008-04-22 19:55:09 -04:00
extable.c
fork.c	x86: fpu xstate split fix	2008-04-19 19:19:55 +02:00
futex_compat.c	futex_compat __user annotation	2008-03-30 14:18:41 -07:00
futex.c	NULL noise: fs/*, mm/*, kernel/*	2008-03-30 14:18:41 -07:00
hrtimer.c	hrtimer: optimize the softirq time optimization	2008-04-21 07:59:51 +02:00
itimer.c	ITIMER_REAL: convert to use struct pid	2008-02-08 09:22:29 -08:00
kallsyms.c	remove support for un-needed _extratext section	2008-02-06 10:41:01 -08:00
Kconfig.hz
Kconfig.preempt	rcu: move PREEMPT_RCU config option back under PREEMPT	2008-03-10 18:01:20 -07:00
kexec.c	kernel: Remove unnecessary inclusions of asm/semaphore.h	2008-04-18 22:17:04 -04:00
kfifo.c
kgdb.c	kgdb: always use icache flush for sw breakpoints	2008-04-17 20:05:43 +02:00
kmod.c	generic: use new set_cpus_allowed_ptr function	2008-04-19 19:44:58 +02:00
kprobes.c	kprobes: fix a null pointer bug in register_kretprobe()	2008-03-04 16:35:19 -08:00
ksysfs.c
kthread.c	Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc	2008-04-21 15:41:27 -07:00
latencytop.c	latencytop: optimize LT_BACKTRACEDEPTH loops a bit	2008-04-19 19:44:57 +02:00
lockdep_internals.h
lockdep_proc.c
lockdep.c	Subject: lockdep: include all lock classes in all_lock_classes	2008-02-25 23:03:02 +01:00
Makefile	Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb	2008-04-18 08:37:01 -07:00
marker.c	markers: use synchronize_sched()	2008-04-02 15:28:19 -07:00
module.c	kernel: Remove unnecessary inclusions of asm/semaphore.h	2008-04-18 22:17:04 -04:00
mutex-debug.c	kernel: remove fastcall in kernel/*	2008-02-08 09:22:31 -08:00
mutex-debug.h
mutex.c	kernel: remove fastcall in kernel/*	2008-02-08 09:22:31 -08:00
mutex.h
notifier.c	kernel/notifier.c should #include <linux/reboot.h>	2008-02-06 10:41:02 -08:00
ns_cgroup.c
nsproxy.c	namespaces: move the IPC namespace under IPC_NS option	2008-02-08 09:22:23 -08:00
panic.c	ACPI: Taint kernel on ACPI table override (format corrected)	2008-02-06 22:07:51 -05:00
params.c	Add new string functions strict_strto* and convert kernel params to use them	2008-02-08 09:22:41 -08:00
pid_namespace.c	namespaces: cleanup the code managed with PID_NS option	2008-02-08 09:22:23 -08:00
pid.c	kernel: remove fastcall in kernel/*	2008-02-08 09:22:31 -08:00
pm_qos_params.c
posix-cpu-timers.c	posix-timers: fix shadowed variables	2008-04-17 12:22:30 +02:00
posix-timers.c	kernel: Remove unnecessary inclusions of asm/semaphore.h	2008-04-18 22:17:04 -04:00
printk.c	Fix locking bug in "acquire_console_semaphore_for_printk()"	2008-04-15 13:09:54 -07:00
profile.c	kernel: Remove unnecessary inclusions of asm/semaphore.h	2008-04-18 22:17:04 -04:00
ptrace.c	ptrace: compat_ptrace_request siginfo	2008-04-21 15:53:41 -07:00
rcuclassic.c
rcupdate.c	rcupdate: fix comment	2008-02-13 16:21:18 -08:00
rcupreempt_trace.c
rcupreempt.c	generic: reduce stack pressure in sched_affinity	2008-04-19 19:44:59 +02:00
rcutorture.c	generic: use new set_cpus_allowed_ptr function	2008-04-19 19:44:58 +02:00
relay.c	relay: set an spd_release() hook for splice	2008-03-26 12:04:09 +01:00
res_counter.c	Memory Resource Controller use strstrip while parsing arguments	2008-03-04 16:35:09 -08:00
resource.c	PCI: clean up resource alignment management	2008-04-20 21:47:08 -07:00
rtmutex_common.h	Don't operate with pid_t in rtmutex tester	2008-02-08 09:22:41 -08:00
rtmutex-debug.c	Don't operate with pid_t in rtmutex tester	2008-02-08 09:22:41 -08:00
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c	hrtimer: more hrtimer_init_sleeper() fallout.	2008-02-13 15:45:36 +01:00
rtmutex.h
rwsem.c
sched_debug.c	sched: build fix	2008-04-19 19:45:01 +02:00
sched_fair.c	sched: debug: show a weight tree	2008-04-19 19:45:00 +02:00
sched_features.h	sched: /debug/sched_features	2008-04-19 19:45:00 +02:00
sched_idletask.c
sched_rt.c	sched: rt-group: optimize dequeue_rt_stack	2008-04-19 19:45:00 +02:00
sched_stats.h	cpumask: use new cpus_scnprintf function	2008-04-19 19:44:59 +02:00
sched.c	sched: fix share (re)distribution	2008-04-25 00:25:08 +02:00
seccomp.c
semaphore.c	Improve semaphore documentation	2008-04-17 10:43:01 -04:00
signal.c	trivial: small cleanups	2008-04-21 22:15:06 +00:00
softirq.c	tasklets: execute tasklets in the same order they were queued	2008-04-19 19:44:58 +02:00
softlockup.c	softlockup: fix task state setting	2008-02-29 18:46:53 +01:00
spinlock.c
srcu.c	make srcu_readers_active() static	2008-02-06 10:41:02 -08:00
stacktrace.c
stop_machine.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial	2008-04-21 16:36:46 -07:00
sys_ni.c
sys.c	generic, x86: add prctl commands PR_GET_TSC and PR_SET_TSC	2008-04-19 19:19:55 +02:00
sysctl_check.c	constify tables in kernel/sysctl_check.c	2008-02-08 09:22:31 -08:00
sysctl.c	sched: rt-group: synchonised bandwidth period	2008-04-19 19:44:57 +02:00
taskstats.c
test_kprobes.c	kprobes: kretprobe user entry-handler	2008-02-06 10:41:11 -08:00
time.c	time: Export set_normalized_timespec.	2008-04-21 19:45:12 -07:00
timeconst.pl	timeconst.pl: correct reversal of USEC_TO_HZ and HZ_TO_USEC	2008-02-12 14:29:26 -08:00
timer.c	timers: simplify lockdep handling	2008-04-17 12:22:31 +02:00
tsacct.c
uid16.c	asmlinkage_protect replaces prevent_tail_call	2008-04-10 17:28:26 -07:00
user_namespace.c	namespaces: cleanup the code managed with the USER_NS option	2008-02-08 09:22:23 -08:00
user.c	sched: fix the task_group hierarchy for UID grouping	2008-04-19 19:45:00 +02:00
utsname_sysctl.c
utsname.c
wait.c	kernel: remove fastcall in kernel/*	2008-02-08 09:22:31 -08:00
workqueue.c	timer_list: add annotations to workqueue.c	2008-04-17 12:22:30 +02:00