[PATCH 14/30] perf hists: Clear dummy entry accumulated period
From: Arnaldo Carvalho de Melo
Date: Wed Apr 27 2016 - 10:41:55 EST
From: Kan Liang <kan.liang@xxxxxxxxx>
The accumulated period for dummy entry should also be 0. Otherwise, the
total overhead could be overcounted.
$ perf record -e '{LLC-load-misses,cpu/instructions/}' --call-graph=lbr ./tchain
$ perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
# Total Lost Samples: 0
#
# Samples: 21K of event 'anon group { LLC-load-misses, cpu/instructions/ }'
# Event count (approx.): 16313667937
#
# Children Self Command Shared Object Symbol
# ................ ................ ........... ................ ............................
#
4769.98% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] update_fast_timekeeper
4356.18% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] trigger_load_balance
3181.12% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] irq_work_tick
1592.37% 0.00% 0.00% 0.00% tchain_edit [kernel.vmlinux] [k] cpu_needs_another_gp
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1461565689-5862-1-git-send-email-kan.liang@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/hist.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 991a351a8a41..0f33d7e698c4 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -2062,6 +2062,8 @@ static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
if (he) {
memset(&he->stat, 0, sizeof(he->stat));
he->hists = hists;
+ if (symbol_conf.cumulate_callchain)
+ memset(he->stat_acc, 0, sizeof(he->stat));
rb_link_node(&he->rb_node_in, parent, p);
rb_insert_color(&he->rb_node_in, root);
hists__inc_stats(hists, he);
--
2.5.5