path: root/tools/perf/builtin-diff.c
diff options
authorNamhyung Kim <>2014-04-22 11:44:21 +0900
committerJiri Olsa <>2014-04-24 16:32:15 +0200
commit820bc81f4cdaac09a8f25040d3a20d86f3da292b (patch)
treeafb1ff42a151339c55782af3b626078a81b21fd1 /tools/perf/builtin-diff.c
parent87e90f43285f4096e9ba5fc18b05c2e04caf3fab (diff)
perf tools: Account entry stats when it's added to the output tree
Currently, accounting each sample is done in multiple places - once when adding them to the input tree, other when adding them to the output tree. It's not only confusing but also can cause a subtle problem since concurrent processing like in perf top might see the updated stats before adding entries into the output tree - like seeing more (blank) lines at the end and/or slight inaccurate percentage. To fix this, only account the entries when it's moved into the output tree so that they cannot be seen prematurely. There're some exceptional cases here and there - they should be addressed separately with comments. Signed-off-by: Namhyung Kim <> Link: Signed-off-by: Jiri Olsa <>
Diffstat (limited to 'tools/perf/builtin-diff.c')
1 files changed, 9 insertions, 4 deletions
diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index 52d91ac4e6c8..f3b10dcf6838 100644
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -341,11 +341,16 @@ static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
return -1;
- if (al.filtered == 0) {
- evsel->hists.stats.total_non_filtered_period += sample->period;
- evsel->hists.nr_non_filtered_entries++;
- }
+ /*
+ * The total_period is updated here before going to the output
+ * tree since normally only the baseline hists will call
+ * hists__output_resort() and precompute needs the total
+ * period in order to sort entries by percentage delta.
+ */
evsel->hists.stats.total_period += sample->period;
+ if (!al.filtered)
+ evsel->hists.stats.total_non_filtered_period += sample->period;
return 0;