diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2009-08-06 18:06:26 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-08-06 20:25:18 +0200 |
| commit | 1054598cab8674438675085fae459e960eb10799 (patch) | |
| tree | 9dcf2c60080e8275bded902f7a08ebcd8140dfcc /kernel | |
| parent | 9424edc2da097c8589fcc24a72552d33e54be161 (diff) | |
| download | lwn-1054598cab8674438675085fae459e960eb10799.tar.gz lwn-1054598cab8674438675085fae459e960eb10799.zip | |
perf_counter: Fix double list iteration in per task precise stats
Brice Goglin reported this crash with per task precise stats:
> I finally managed to test the threaded perfcounter statistics (thanks a
> lot for implementing it). I am running 2.6.31-rc5 (with the AMD
> magny-cours patches but I don't think they matter here). I am trying to
> measure local/remote memory accesses per thread during the well-known
> stream benchmark. It's compiled with OpenMP using 16 threads on a
> quad-socket quad-core barcelona machine.
>
> Command line is:
> /mnt/scratch/bgoglin/cpunode/linux-2.6.31/tools/perf/perf record -f -s
> -e r1000001e0 -e r1000002e0 -e r1000004e0 -e r1000008e0 ./stream
>
> It seems to work fine with a single -e <counter> on the command line
> while it crashes when there are at least 2 of them.
> It seems to work fine without -s as well.
A silly copy-paste resulted in a messed up iteration which would
cause the OOPS.
Reported-by: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Brice Goglin <Brice.Goglin@inria.fr>
LKML-Reference: <1249574786.32113.550.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/perf_counter.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 199ed4771315..673c1aaf7332 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1104,7 +1104,7 @@ static void perf_counter_sync_stat(struct perf_counter_context *ctx, __perf_counter_sync_stat(counter, next_counter); counter = list_next_entry(counter, event_entry); - next_counter = list_next_entry(counter, event_entry); + next_counter = list_next_entry(next_counter, event_entry); } } |