linux/kernel
Peter Zijlstra (Intel) 8f95b435b6 perf: Fix move_group() order
Jiri reported triggering the new WARN_ON_ONCE in event_sched_out over
the weekend:

  event_sched_out.isra.79+0x2b9/0x2d0
  group_sched_out+0x69/0xc0
  ctx_sched_out+0x106/0x130
  task_ctx_sched_out+0x37/0x70
  __perf_install_in_context+0x70/0x1a0
  remote_function+0x48/0x60
  generic_exec_single+0x15b/0x1d0
  smp_call_function_single+0x67/0xa0
  task_function_call+0x53/0x80
  perf_install_in_context+0x8b/0x110

I think the below should cure this; if we install a group leader it
will iterate the (still intact) group list and find its siblings and
try and install those too -- even though those still have the old
event->ctx -- in the new ctx.

Upon installing the first group sibling we'd try and schedule out the
group and trigger the above warn.

Fix this by installing the group leader last, installing siblings
would have no effect, they're not reachable through the group lists
and therefore we don't schedule them.

Also delay resetting the state until we're absolutely sure the events
are quiescent.

Reported-by: Jiri Olsa <jolsa@redhat.com>
Reported-by: vincent.weaver@maine.edu
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150126162639.GA21418@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:11 +01:00
..
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-01-27 13:55:36 -08:00
configs
debug Surprising number of fixes this merge window :( 2015-01-23 06:40:36 +12:00
events perf: Fix move_group() order 2015-02-04 08:07:11 +01:00
gcov
irq
locking mutex: Always clear owner field upon mutex_unlock() 2015-01-09 11:20:39 +01:00
power
printk
rcu
sched Linux 3.19-rc7 2015-02-04 07:58:29 +01:00
time Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-01-25 17:47:34 -08:00
trace Merge branch 'perf/urgent' into perf/core, to pick up fixes 2015-01-28 15:42:56 +01:00
.gitignore
acct.c
async.c
audit_tree.c
audit_watch.c
audit.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-12-30 10:45:47 -08:00
audit.h
auditfilter.c Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit 2014-12-23 18:13:16 -08:00
auditsc.c Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit 2014-12-31 14:52:18 -08:00
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c
cgroup.c cgroup: prevent mount hang due to memory controller lifetime 2015-01-22 10:26:43 -05:00
compat.c
configs.c
context_tracking.c
cpu_pm.c
cpu.c
cpuset.c
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c exit: fix race between wait_consider_task() and wait_task_zombie() 2015-01-08 15:10:51 -08:00
extable.c
fork.c
freezer.c
futex_compat.c
futex.c
groups.c
hung_task.c
irq_work.c
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c
kmod.c
kprobes.c module: remove mod arg from module_free, rename module_memfree(). 2015-01-20 11:38:33 +10:30
ksysfs.c
kthread.c
latencytop.c
Makefile
module_signing.c
module-internal.h
module.c module: make module_refcount() a signed integer. 2015-01-22 11:15:54 +10:30
notifier.c
nsproxy.c
padata.c
panic.c
params.c param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC 2015-01-20 11:38:31 +10:30
pid_namespace.c
pid.c
profile.c
ptrace.c
range.c kernel: avoid overflow in cmp_range 2015-01-17 10:02:23 +13:00
reboot.c
relay.c
resource.c
seccomp.c
signal.c
smp.c
smpboot.c
smpboot.h
softirq.c
stacktrace.c
stop_machine.c
sys_ni.c
sys.c x86, mpx: Strictly enforce empty prctl() args 2015-01-22 21:11:06 +01:00
sysctl_binary.c
sysctl.c
system_certificates.S
system_keyring.c
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c
tsacct.c
uid16.c
up.c
user_namespace.c
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
watchdog.c
workqueue_internal.h
workqueue.c workqueue: fix subtle pool management issue which can stall whole worker_pool 2015-01-16 14:21:16 -05:00