3.0-stable review patch. If anyone has any objections, please let me know.
------------------ From: "Naveen N. Rao" <[email protected]> commit a4a03fc7ef89020baca4f19174e6a43767c6d78a upstream. This patch fixes an issue where perf report shows nan% for certain perf.data files. The below is from a report for a do_fork probe: -nan% sshd [kernel.kallsyms] [k] do_fork -nan% packagekitd [kernel.kallsyms] [k] do_fork -nan% dbus-daemon [kernel.kallsyms] [k] do_fork -nan% bash [kernel.kallsyms] [k] do_fork A git bisect shows commit f3bda2c as the cause. However, looking back through the git history, I saw commit 640c03c which seems to have removed the required initialization for perf_sample->period. The problem only started showing after commit f3bda2c. The below patch re-introduces the initialization and it fixes the problem for me. With the below patch, for the same perf.data: 73.08% bash [kernel.kallsyms] [k] do_fork 8.97% 11-dhclient [kernel.kallsyms] [k] do_fork 6.41% sshd [kernel.kallsyms] [k] do_fork 3.85% 20-chrony [kernel.kallsyms] [k] do_fork 2.56% sendmail [kernel.kallsyms] [k] do_fork This patch applies over current linux-tip commit 9949284. Problem introduced in: $ git describe 640c03c v2.6.37-rc3-83-g640c03c Cc: Ananth N Mavinakayanahalli <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Robert Richter <[email protected]> Cc: Srikar Dronamraju <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Naveen N. Rao <[email protected]> Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- tools/perf/util/evsel.c | 1 + 1 file changed, 1 insertion(+) --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -348,6 +348,7 @@ int perf_event__parse_sample(const union data->cpu = data->pid = data->tid = -1; data->stream_id = data->id = data->time = -1ULL; + data->period = 1; if (event->header.type != PERF_RECORD_SAMPLE) { if (!sample_id_all) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
