kernel_optimize_test/kernel
Tejun Heo cd3d095275 cgroup: always lock threadgroup during migration
Update cgroup to take advantage of the fack that threadgroup_lock()
guarantees stable threadgroup.

* Lock threadgroup even if the target is a single task.  This
  guarantees that when the target tasks stay stable during migration
  regardless of the target type.

* Remove PF_EXITING early exit optimization from attach_task_by_pid()
  and check it in cgroup_task_migrate() instead.  The optimization was
  for rather cold path to begin with and PF_EXITING state can be
  trusted throughout migration by checking it after locking
  threadgroup.

* Don't add PF_EXITING tasks to target task array in
  cgroup_attach_proc().  This ensures that task migration is performed
  only for live tasks.

* Remove -ESRCH failure path from cgroup_task_migrate().  With the
  above changes, it's guaranteed to be called only for live tasks.

After the changes, only live tasks are migrated and they're guaranteed
to stay alive until migration is complete.  This removes problems
caused by exec and exit racing against cgroup migration including
symmetry among cgroup attach methods and different cgroup methods
racing each other.

v2: Oleg pointed out that one more PF_EXITING check can be removed
    from cgroup_attach_proc().  Removed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2011-12-12 18:12:21 -08:00
..
debug Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
events Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
gcov gcov: disable CONSTRUCTORS for UML 2011-07-26 16:49:45 -07:00
irq Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-11-17 11:46:26 -02:00
power Merge branch 'pm-freezer' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into pm-freezer 2011-11-23 21:09:02 +01:00
time kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
trace kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
.gitignore
acct.c
async.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
audit_tree.c audit_tree,rcu: Convert call_rcu(__put_tree) to kfree_rcu() 2011-07-20 14:10:11 -07:00
audit_watch.c
audit.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
audit.h
auditfilter.c
auditsc.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
backtracetest.c
bounds.c
capability.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
cgroup_freezer.c freezer: remove unused @sig_only from freeze_task() 2011-11-21 12:32:26 -08:00
cgroup.c cgroup: always lock threadgroup during migration 2011-12-12 18:12:21 -08:00
compat.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
configs.c kernel/configs.c: include MODULE_*() when CONFIG_IKCONFIG_PROC=n 2011-07-25 20:57:15 -07:00
cpu_pm.c cpu_pm: call notifiers during suspend 2011-09-23 12:05:29 +05:30
cpu.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
cpuset.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
crash_dump.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
cred.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
delayacct.c KVM: Steal time implementation 2011-07-14 12:59:14 +03:00
dma.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
elfcore.c
exec_domain.c
exit.c freezer: remove racy clear_freeze_flag() and set PF_NOFREEZE on dead tasks 2011-11-21 12:32:23 -08:00
extable.c extable, core_kernel_data(): Make sure all archs define _sdata 2011-05-20 08:56:56 +02:00
fork.c threadgroup: rename signal->threadgroup_fork_lock to ->group_rwsem 2011-12-12 18:12:21 -08:00
freezer.c freezer: kill unused set_freezable_with_signal() 2011-11-23 09:28:17 -08:00
futex_compat.c
futex.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
groups.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
hrtimer.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
hung_task.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
irq_work.c kernel: fix two implicit header assumptions in irq_work.c 2011-10-31 09:20:12 -04:00
itimer.c
jump_label.c jump-label: initialize jump-label subsystem much earlier 2011-10-25 11:55:15 -07:00
kallsyms.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt sched: Isolate preempt counting in its own config option 2011-06-10 15:15:40 +02:00
kexec.c [S390] kdump: Add infrastructure for unmapping crashkernel memory 2011-10-30 15:16:42 +01:00
kfifo.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
kmod.c kmod: prevent kmod_loop_msg overflow in __request_module() 2011-10-26 13:10:39 +10:30
kprobes.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
ksysfs.c kernel: ksysfs.c is implicitly using stat.h 2011-10-31 09:20:13 -04:00
kthread.c freezer: kill unused set_freezable_with_signal() 2011-11-23 09:28:17 -08:00
latencytop.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
lockdep_internals.h
lockdep_proc.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
lockdep_states.h
lockdep.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-26 16:26:53 +02:00
Makefile Merge branch 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm 2011-10-28 12:02:27 -07:00
module.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mutex-debug.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mutex-debug.h
mutex.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mutex.h
notifier.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
nsproxy.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
padata.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
panic.c module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree 2011-11-07 07:54:42 +10:30
params.c kernel: params.c needs module.h not moduleparam.h 2011-10-31 09:20:13 -04:00
pid_namespace.c
pid.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
posix-cpu-timers.c Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-26 16:17:32 +02:00
posix-timers.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
printk.c printk: remove bounds checking for log_prefix 2011-10-31 17:30:53 -07:00
profile.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
ptrace.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
range.c range: fix bogus misuse of module.h to get printk() 2011-10-31 09:20:11 -04:00
rcu.h rcu: Add grace-period, quiescent-state, and call_rcu trace events 2011-09-28 21:38:21 -07:00
rcupdate.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rcutiny_plugin.h kernel: fix up module header handling in rcutiny files 2011-10-31 09:20:13 -04:00
rcutiny.c kernel: fix up module header handling in rcutiny files 2011-10-31 09:20:13 -04:00
rcutorture.c rcu: Make rcu_torture_boost() exit loops at end of test 2011-09-28 21:38:46 -07:00
rcutree_plugin.h rcu: Remove rcu_needs_cpu_flush() to avoid false quiescent states 2011-09-28 21:38:48 -07:00
rcutree_trace.c rcu: Simplify quiescent-state accounting 2011-09-28 21:38:22 -07:00
rcutree.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rcutree.h rcu: Remove rcu_needs_cpu_flush() to avoid false quiescent states 2011-09-28 21:38:48 -07:00
relay.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
res_counter.c
resource.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rtmutex_common.h
rtmutex-debug.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rtmutex-debug.h
rtmutex-tester.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rtmutex.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rtmutex.h
rwsem.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
sched_autogroup.c
sched_autogroup.h sched: Skip autogroup when looking for all rt sched groups 2011-07-01 10:39:08 +02:00
sched_clock.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
sched_cpupri.c sched/cpupri: Remove cpupri->pri_active 2011-08-14 12:01:11 +02:00
sched_cpupri.h sched/cpupri: Remove cpupri->pri_active 2011-08-14 12:01:11 +02:00
sched_debug.c
sched_fair.c sched: Wrap scheduler p->cpus_allowed access 2011-10-06 12:46:56 +02:00
sched_features.h sched: Kill WAKEUP_PREEMPT 2011-08-14 12:00:41 +02:00
sched_idletask.c
sched_rt.c sched: Warn on rt throttling 2011-10-06 12:47:04 +02:00
sched_stats.h locking, sched: Annotate thread_group_cputimer as raw 2011-09-13 11:11:55 +02:00
sched_stoptask.c sched: Implement hierarchical task accounting for SCHED_OTHER 2011-08-14 12:01:13 +02:00
sched.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-11-06 17:12:03 -08:00
seccomp.c
semaphore.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
signal.c threadgroup: extend threadgroup_lock() to cover exit and exec 2011-12-12 18:12:21 -08:00
smp.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
softirq.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
spinlock.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
srcu.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
stacktrace.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
stop_machine.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
sys_ni.c Cross Memory Attach 2011-10-31 17:30:44 -07:00
sys.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
sysctl_binary.c ipv4: NET_IPV4_ROUTE_GC_INTERVAL removal 2011-10-03 14:13:01 -04:00
sysctl_check.c xfs: remove subdirectories 2011-08-12 16:21:35 -05:00
sysctl.c Merge branch 'akpm' (Andrew's incoming) 2011-10-31 17:46:07 -07:00
taskstats.c Make TASKSTATS require root access 2011-09-19 17:04:37 -07:00
test_kprobes.c
time.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
timeconst.pl
timer.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
tracepoint.c Tracepoint: Dissociate from module mutex 2011-08-10 20:38:14 -04:00
tsacct.c Make taskstats round statistics down to nearest 1k bytes/events 2011-09-19 17:10:57 -07:00
uid16.c
up.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
user_namespace.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
user-return-notifier.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
user.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
utsname_sysctl.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
utsname.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
wait.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
watchdog.c watchdog: move watchdog_*_all_cpus under CONFIG_SYSCTL 2011-10-31 17:30:53 -07:00
workqueue_sched.h
workqueue.c kernel: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00