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perf stat: Skip duration_time in setup_system_wide

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Some metrics (such as DRAM_BW_Use) consists of uncore events and
duration_time. For uncore events, counter->core.system_wide is true. But
for duration_time, counter->core.system_wide is false so
target.system_wide is set to false.

Then 'enable_on_exec' is set in perf_event_attr of uncore event.  Kernel
will return error when trying to open the uncore event.

This patch skips the duration_time in setup_system_wide then
target.system_wide will be set to true for the evlist of uncore events +
duration_time.

Before (tested on skylake desktop):

  # perf stat -M DRAM_BW_Use -- sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (arb/event=0x84,umask=0x1/).
  /bin/dmesg | grep -i perf may provide additional information.

After:

  # perf stat -M DRAM_BW_Use -- sleep 1

   Performance counter stats for 'system wide':

                169      arb/event=0x84,umask=0x1/ #     0.00 DRAM_BW_Use
             40,427      arb/event=0x81,umask=0x1/
      1,000,902,197 ns   duration_time

        1.000902197 seconds time elapsed

Fixes: e3ba76deef23064f ("perf tools: Force uncore events to system wide monitoring")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200922015004.30114-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jin Yao 2020-09-22 09:50:04 +08:00 committed by Arnaldo Carvalho de Melo
parent d110162caf
commit 002a3d690f
1 changed files with 3 additions and 1 deletions
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4
tools/perf/builtin-stat.c
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@ -2024,8 +2024,10 @@ static void setup_system_wide(int forks)
struct evsel *counter;
evlist__for_each_entry(evsel_list, counter) {
if (!counter->core.system_wide)
if (!counter->core.system_wide &&
strcmp(counter->name, "duration_time")) {
return;
}
}
if (evsel_list->core.nr_entries)