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author | Ramkumar Ramachandra <artagnon@gmail.com> | 2013-09-30 16:43:05 +0530 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2013-10-11 12:17:33 -0300 |
commit | c458fe62ca31496664c1211a7906d261220b18f9 (patch) | |
tree | 93ae1d9609c7f06dd18299f9114e638e29b640f5 | |
parent | 820042233bd3c1b24b5ca4c75a88a4e0de39814a (diff) | |
download | op-kernel-dev-c458fe62ca31496664c1211a7906d261220b18f9.zip op-kernel-dev-c458fe62ca31496664c1211a7906d261220b18f9.tar.gz |
perf stat: Don't print bogus data on -e cycles
When only the cycles event is requested:
$ perf stat -e cycles dd if=/dev/zero of=/dev/null count=1000000
1000000+0 records in
1000000+0 records out
512000000 bytes (512 MB) copied, 0.26123 s, 2.0 GB/s
Performance counter stats for 'dd if=/dev/zero of=/dev/null count=1000000':
911,626,453 cycles # 0.000 GHz
0.262113350 seconds time elapsed
The 0.000 GHz comment in the output is totally bogus and misleading. It
happens because update_shadow_stats() doesn't touch runtime_nsecs_stats;
it is only written when a requested counter matches a SW_TASK_CLOCK. In
our case, since we have only requested HW_CPU_CYCLES,
runtime_nsecs_stats is unavailable. So, omit printing the comment
altogether.
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1380539585-23859-3-git-send-email-artagnon@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-rw-r--r-- | tools/perf/builtin-stat.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index 700b478..ce2266c 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -997,10 +997,10 @@ static void abs_printout(int cpu, int nr, struct perf_evsel *evsel, double avg) } else if (perf_evsel__match(evsel, HARDWARE, HW_CPU_CYCLES)) { total = avg_stats(&runtime_nsecs_stats[cpu]); - if (total) - ratio = 1.0 * avg / total; - - fprintf(output, " # %8.3f GHz ", ratio); + if (total) { + ratio = avg / total; + fprintf(output, " # %8.3f GHz ", ratio); + } } else if (transaction_run && perf_evsel__cmp(evsel, nth_evsel(T_CYCLES_IN_TX))) { total = avg_stats(&runtime_cycles_stats[cpu]); |