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>
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