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Ian Rogers dcffc5ebb8 perf evsel: Improve error message for uncore events
When a group has multiple events and the leader fails it can yield
errors like:

  $ perf stat -e '{uncore_imc/cas_count_read/},instructions' /bin/true
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_imc/cas_count_read/).
  /bin/dmesg | grep -i perf may provide additional information.

However, when not the group leader <not supported> is given:

  $ perf stat -e '{instructions,uncore_imc/cas_count_read/}' /bin/true
  ...
           1,619,057      instructions
     <not supported> MiB  uncore_imc/cas_count_read/

This is necessary because get_group_fd will fail if the leader fails and
is the direct result of the check on line 750 of builtin-stat.c in
stat_handle_error that returns COUNTER_SKIP for the latter case.

This patch improves the error message to:

  $ perf stat -e '{uncore_imc/cas_count_read/},instructions' /bin/true
  Error:
  Invalid event (uncore_imc/cas_count_read/) in per-thread mode, enable system wide with '-a'.

v2. Changed the test to use !target__has_cpu as suggested by Namhyung Kim.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20211223183948.3423989-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
History 2022-01-12 14:28:21 -03:00
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