diff options
author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-08-13 13:47:54 +0400 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-08-13 14:58:05 +0400 |
commit | 970892a9031a5dc7217bd394fb9d89fa75a4a7bc (patch) | |
tree | d6d5eee6d24cde67c279d5cc753512fc85cd9e5b | |
parent | 3dab77fb1bf89664bb1c9544607159dcab6f7d57 (diff) | |
download | linux-970892a9031a5dc7217bd394fb9d89fa75a4a7bc.tar.xz |
perf_counter: Fix an ipi-deadlock
perf_pending_counter() is called from IRQ context and will call
perf_counter_disable(), however perf_counter_disable() uses
smp_call_function_single() which doesn't fancy being used with
IRQs disabled due to IPI deadlocks.
Fix this by making it use the local __perf_counter_disable()
call and teaching the counter_sched_out() code about pending
disables as well.
This should cover the case where a counter migrates before the
pending queue gets processed.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey J Ashford <cjashfor@us.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
LKML-Reference: <20090813103655.244097721@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r-- | kernel/perf_counter.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index b8c6b97a20a3..3f841beefc7b 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -307,6 +307,10 @@ counter_sched_out(struct perf_counter *counter, return; counter->state = PERF_COUNTER_STATE_INACTIVE; + if (counter->pending_disable) { + counter->pending_disable = 0; + counter->state = PERF_COUNTER_STATE_OFF; + } counter->tstamp_stopped = ctx->time; counter->pmu->disable(counter); counter->oncpu = -1; @@ -2343,7 +2347,7 @@ static void perf_pending_counter(struct perf_pending_entry *entry) if (counter->pending_disable) { counter->pending_disable = 0; - perf_counter_disable(counter); + __perf_counter_disable(counter); } if (counter->pending_wakeup) { |