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authorZhouyi Zhou2013-10-24 09:43:33 +0200
committerArnaldo Carvalho de Melo2013-10-28 20:06:00 +0100
commit8e50d384cc1d5afd2989cf0f7093756ed7164eb2 (patch)
tree87e34b49783a32d8552eaad510d0b5fba94ee08e /tools/perf/tests/sw-clock.c
parentperf top: Split -G and --call-graph (diff)
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perf tools: Fixup mmap event consumption
The tail position of the event buffer should only be modified after actually use that event. If not the event buffer could be invalid before use, and segment fault occurs when invoking perf top -G. Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Cc: David Ahern <dsahern@gmail.com> Cc: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Link: http://lkml.kernel.org/r/1382600613-32177-1-git-send-email-zhouzhouyi@gmail.com [ Simplified the logic using exit gotos and renamed write_tail method to mmap_consume ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/tests/sw-clock.c')
-rw-r--r--tools/perf/tests/sw-clock.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c
index 2e41e2d32ccc..6e2b44ec0749 100644
--- a/tools/perf/tests/sw-clock.c
+++ b/tools/perf/tests/sw-clock.c
@@ -78,7 +78,7 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
struct perf_sample sample;
if (event->header.type != PERF_RECORD_SAMPLE)
- continue;
+ goto next_event;
err = perf_evlist__parse_sample(evlist, event, &sample);
if (err < 0) {
@@ -88,6 +88,8 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
total_periods += sample.period;
nr_samples++;
+next_event:
+ perf_evlist__mmap_consume(evlist, 0);
}
if ((u64) nr_samples == total_periods) {