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perf stat: Check existence of frontend/backed stalled cycles

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Only put the frontend/backend stalled cycles into the default perf stat
events when the CPU actually supports them.

This avoids empty columns with --metric-only on newer Intel CPUs.

Committer note:

Before:

  $ perf stat ls

    Performance counter stats for 'ls':

          1.080893     task-clock (msec)      #    0.619 CPUs utilized
                 0     context-switches       #    0.000 K/sec
                 0     cpu-migrations         #    0.000 K/sec
                97     page-faults            #    0.090 M/sec
         3,327,741     cycles                 #    3.079 GHz
   <not supported>     stalled-cycles-frontend
   <not supported>     stalled-cycles-backend
         1,609,544     instructions           #    0.48  insn per cycle
           319,117     branches               #  295.235 M/sec
            12,246     branch-misses          #    3.84% of all branches

       0.001746508 seconds time elapsed
  $

After:

  $ perf stat ls

    Performance counter stats for 'ls':

          0.693948     task-clock (msec)      #    0.662 CPUs utilized
                 0     context-switches       #    0.000 K/sec
                 0     cpu-migrations         #    0.000 K/sec
                95     page-faults            #    0.137 M/sec
         1,792,509     cycles                 #    2.583 GHz
         1,599,047     instructions           #    0.89  insn per cycle
           316,328     branches               #  455.838 M/sec
            12,453     branch-misses          #    3.94% of all branches

       0.001048987 seconds time elapsed
  $

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456532881-26621-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Andi Kleen 2016-02-26 16:27:56 -08:00 committed by Arnaldo Carvalho de Melo
parent f9a5978ac4
commit 9dec4473ab
1 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
tools/perf/builtin-stat.c
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@ -1441,7 +1441,7 @@ static int perf_stat_init_aggr_mode_file(struct perf_stat *st)
*/
static int add_default_attributes(void)
{
struct perf_event_attr default_attrs[] = {
struct perf_event_attr default_attrs0[] = {
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK },
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES },
@ -1449,8 +1449,14 @@ static int add_default_attributes(void)
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES },
};
struct perf_event_attr frontend_attrs[] = {
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_STALLED_CYCLES_FRONTEND },
};
struct perf_event_attr backend_attrs[] = {
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_STALLED_CYCLES_BACKEND },
};
struct perf_event_attr default_attrs1[] = {
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_MISSES },
@ -1567,7 +1573,19 @@ static int add_default_attributes(void)
}
if (!evsel_list->nr_entries) {
if (perf_evlist__add_default_attrs(evsel_list, default_attrs) < 0)
if (perf_evlist__add_default_attrs(evsel_list, default_attrs0) < 0)
return -1;
if (pmu_have_event("cpu", "stalled-cycles-frontend")) {
if (perf_evlist__add_default_attrs(evsel_list,
frontend_attrs) < 0)
return -1;
}
if (pmu_have_event("cpu", "stalled-cycles-backend")) {
if (perf_evlist__add_default_attrs(evsel_list,
backend_attrs) < 0)
return -1;
}
if (perf_evlist__add_default_attrs(evsel_list, default_attrs1) < 0)
return -1;
}