From: sukadev@linux.vnet.ibm.com Date: Thu, 24 Jan 2013 13:25:23 +0000 (+0000) Subject: perf/Power: PERF_EVENT_IOC_ENABLE does not reenable event X-Git-Tag: v3.9-rc1~100^2~37 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f53d168c025f27d64417a56bf129dbb39d2e1189;p=pandora-kernel.git perf/Power: PERF_EVENT_IOC_ENABLE does not reenable event perf/Power: PERF_EVENT_IOC_ENABLE does not reenable event If we disable a perf event because we exceeded the specified ->event_limit, power_pmu_stop() sets the PERF_HES_STOPPED flag on the event. If the application then re-enables the event using PERF_EVENT_IOC_ENABLE ioctl, we don't ever clear this STOPPED flag. Consequently, the user space is never notified of the event. Following message has more background and test case. http://lists.eecs.utk.edu/pipermail/ptools-perfapi/2012-October/002528.html Used the following test cases to verify that this patch works on latest PAPI. $ papi.git/src/ctests/nonthread PAPI_TOT_CYC@5000000 $ papi.git/src/ctests/overflow_single_event Changelog[v2]: - [Paul Mackerras] Also clear PERF_HES_UPTODATE flag since we are restarting the event; cleanup comments and patch description. Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Benjamin Herrenschmidt --- Reading git-diff-tree failed