• Peter Zijlstra's avatar
    perf_counter: Fix double list iteration in per task precise stats · 1054598c
    Peter Zijlstra authored
    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: default avatarBrice Goglin <Brice.Goglin@inria.fr>
    Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
    Tested-by: default avatarBrice Goglin <Brice.Goglin@inria.fr>
    LKML-Reference: <1249574786.32113.550.camel@twins>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    1054598c
perf_counter.c 109 KB