Commit-ID: 1054598cab8674438675085fae459e960eb10799 Gitweb: http://git.kernel.org/tip/1054598cab8674438675085fae459e960eb10799 Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Thu, 6 Aug 2009 18:06:26 +0200 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Thu, 6 Aug 2009 20:25:18 +0200 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@xxxxxxxx> Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Tested-by: Brice Goglin <Brice.Goglin@xxxxxxxx> LKML-Reference: <1249574786.32113.550.camel@twins> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- 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 199ed47..673c1aa 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); } } -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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