From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
Clark Williams <williams@redhat.com>,
linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
Arnaldo Carvalho de Melo <acme@redhat.com>,
Ravi Bangoria <ravi.bangoria@linux.ibm.com>,
"Naveen N . Rao" <naveen.n.rao@linux.vnet.ibm.com>,
Stephane Eranian <eranian@google.com>,
stable@vger.kernel.org
Subject: [PATCH 26/31] perf stat: Reset previous counts on repeat with interval
Date: Fri, 20 Sep 2019 11:25:37 -0300 [thread overview]
Message-ID: <20190920142542.12047-27-acme@kernel.org> (raw)
In-Reply-To: <20190920142542.12047-1-acme@kernel.org>
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
When using 'perf stat' with repeat and interval option, it shows wrong
values for events.
The wrong values will be shown for the first interval on the second and
subsequent repetitions.
Without the fix:
# perf stat -r 3 -I 2000 -e faults -e sched:sched_switch -a sleep 5
2.000282489 53 faults
2.000282489 513 sched:sched_switch
4.005478208 3,721 faults
4.005478208 2,666 sched:sched_switch
5.025470933 395 faults
5.025470933 1,307 sched:sched_switch
2.009602825 1,84,46,74,40,73,70,95,47,520 faults <------
2.009602825 1,84,46,74,40,73,70,95,49,568 sched:sched_switch <------
4.019612206 4,730 faults
4.019612206 2,746 sched:sched_switch
5.039615484 3,953 faults
5.039615484 1,496 sched:sched_switch
2.000274620 1,84,46,74,40,73,70,95,47,520 faults <------
2.000274620 1,84,46,74,40,73,70,95,47,520 sched:sched_switch <------
4.000480342 4,282 faults
4.000480342 2,303 sched:sched_switch
5.000916811 1,322 faults
5.000916811 1,064 sched:sched_switch
#
prev_raw_counts is allocated when using intervals. This is used when
calculating the difference in the counts of events when using interval.
The current counts are stored in prev_raw_counts to calculate the
differences in the next iteration.
On the first interval of the second and subsequent repetitions,
prev_raw_counts would be the values stored in the last interval of the
previous repetitions, while the current counts will only be for the
first interval of the current repetition.
Hence there is a possibility of events showing up as big number.
Fix this by resetting prev_raw_counts whenever perf stat repeats the
command.
With the fix:
# perf stat -r 3 -I 2000 -e faults -e sched:sched_switch -a sleep 5
2.019349347 2,597 faults
2.019349347 2,753 sched:sched_switch
4.019577372 3,098 faults
4.019577372 2,532 sched:sched_switch
5.019415481 1,879 faults
5.019415481 1,356 sched:sched_switch
2.000178813 8,468 faults
2.000178813 2,254 sched:sched_switch
4.000404621 7,440 faults
4.000404621 1,266 sched:sched_switch
5.040196079 2,458 faults
5.040196079 556 sched:sched_switch
2.000191939 6,870 faults
2.000191939 1,170 sched:sched_switch
4.000414103 541 faults
4.000414103 902 sched:sched_switch
5.000809863 450 faults
5.000809863 364 sched:sched_switch
#
Committer notes:
This was broken since the cset introducing the --interval feature, i.e.
--repeat + --interval wasn't tested at that point, add the Fixes tag so
that automatic scripts can pick this up.
Fixes: 13370a9b5bb8 ("perf stat: Add interval printing")
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: stable@vger.kernel.org # v3.9+
Link: http://lore.kernel.org/lkml/20190904094738.9558-2-srikar@linux.vnet.ibm.com
[ Fixed up conflicts with libperf, i.e. some perf_{evsel,evlist} lost the 'perf' prefix ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-stat.c | 3 +++
tools/perf/util/stat.c | 17 +++++++++++++++++
tools/perf/util/stat.h | 1 +
3 files changed, 21 insertions(+)
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index eece3d1e429a..fa4b148ecfca 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1952,6 +1952,9 @@ int cmd_stat(int argc, const char **argv)
fprintf(output, "[ perf stat: executing run #%d ... ]\n",
run_idx + 1);
+ if (run_idx != 0)
+ perf_evlist__reset_prev_raw_counts(evsel_list);
+
status = run_perf_stat(argc, argv, run_idx);
if (forever && status != -1) {
print_counters(NULL, argc, argv);
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 06571209cb0b..fcd54342c04c 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -162,6 +162,15 @@ static void perf_evsel__free_prev_raw_counts(struct evsel *evsel)
evsel->prev_raw_counts = NULL;
}
+static void perf_evsel__reset_prev_raw_counts(struct evsel *evsel)
+{
+ if (evsel->prev_raw_counts) {
+ evsel->prev_raw_counts->aggr.val = 0;
+ evsel->prev_raw_counts->aggr.ena = 0;
+ evsel->prev_raw_counts->aggr.run = 0;
+ }
+}
+
static int perf_evsel__alloc_stats(struct evsel *evsel, bool alloc_raw)
{
int ncpus = perf_evsel__nr_cpus(evsel);
@@ -212,6 +221,14 @@ void perf_evlist__reset_stats(struct evlist *evlist)
}
}
+void perf_evlist__reset_prev_raw_counts(struct evlist *evlist)
+{
+ struct evsel *evsel;
+
+ evlist__for_each_entry(evlist, evsel)
+ perf_evsel__reset_prev_raw_counts(evsel);
+}
+
static void zero_per_pkg(struct evsel *counter)
{
if (counter->per_pkg_mask)
diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
index 0f9c9f6e2041..edbeb2f63e8d 100644
--- a/tools/perf/util/stat.h
+++ b/tools/perf/util/stat.h
@@ -193,6 +193,7 @@ void perf_stat__collect_metric_expr(struct evlist *);
int perf_evlist__alloc_stats(struct evlist *evlist, bool alloc_raw);
void perf_evlist__free_stats(struct evlist *evlist);
void perf_evlist__reset_stats(struct evlist *evlist);
+void perf_evlist__reset_prev_raw_counts(struct evlist *evlist);
int perf_stat_process_counter(struct perf_stat_config *config,
struct evsel *counter);
--
2.21.0
next prev parent reply other threads:[~2019-09-20 14:27 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-20 14:25 [GIT PULL] perf/core improvements and fixes Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 01/31] perf python: Add missing python/perf.so dependency for libperf Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 02/31] perf tests: Add libperf automated test for 'make -C tools/perf build-test' Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 03/31] libperf: Add missing event.h file to install rule Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 04/31] libperf: Adopt perf_cpu_map__max() function Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 05/31] perf jvmti: Link against tools/lib/string.o to have weak strlcpy() Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 06/31] perf tools: Add PMU event JSON files for ARM Cortex-A76 and, Neoverse N1 Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 07/31] perf tools: Remove needless builtin.h include directives Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 08/31] perf debug: No need to include ui/util.h Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 09/31] perf tools: Remove debug.h from places where it is not needed Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 10/31] perf tools: Remove util.h from " Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 11/31] perf probe: Add missing build-id.h header Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 12/31] perf symbols: Add missing dso.h header Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 13/31] perf env: Remove needless cpumap.h header Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 14/31] perf event: Move perf_event__synthesize* to event.h Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 15/31] perf stat: Move perf_stat_synthesize_config() " Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 16/31] perf callchain: Remove needless event.h include Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 17/31] perf python: Remove debug.h Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 18/31] perf hist: Add missing 'struct branch_stack' forward declaration Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 19/31] perf annotate: Add missing machine.h include directive Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 20/31] perf sched: Add missing event.h " Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 21/31] perf auxtrace: Add missing 'struct perf_sample' forward declaration Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 22/31] perf tools: Move event synthesizing routines to separate header Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 23/31] perf memswap: Adopt 'struct u64_swap' from evsel.h Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 24/31] perf tools: Move event synthesizing routines to separate .c file Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 25/31] tools lib traceevent: Convert remaining %p[fF] users to %p[sS] Arnaldo Carvalho de Melo
2019-09-20 14:25 ` Arnaldo Carvalho de Melo [this message]
2019-09-20 14:25 ` [PATCH 27/31] perf stat: Fix a segmentation fault when using repeat forever Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 28/31] perf test: Fix spelling mistake "allos" -> "allocate" Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 29/31] perf kvm: Move kvm-stat header file from conditional inclusion to common include section Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 30/31] perf kvm: Add arch neutral function to choose event for perf kvm record Arnaldo Carvalho de Melo
2019-09-20 14:25 ` [PATCH 31/31] perf kvm stat: Set 'trace_cycles' as default event for 'perf kvm record' in powerpc Arnaldo Carvalho de Melo
2019-09-20 16:15 ` [GIT PULL] perf/core improvements and fixes Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190920142542.12047-27-acme@kernel.org \
--to=acme@kernel.org \
--cc=acme@redhat.com \
--cc=eranian@google.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=namhyung@kernel.org \
--cc=naveen.n.rao@linux.vnet.ibm.com \
--cc=ravi.bangoria@linux.ibm.com \
--cc=srikar@linux.vnet.ibm.com \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=williams@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).