perf mem: Fix error on hybrid related to availability of mem event in a PMU
authorKan Liang <kan.liang@linux.intel.com>
Tue, 28 Nov 2023 20:39:40 +0000 (12:39 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 25 Jan 2024 23:35:51 +0000 (15:35 -0800)
commit9cc93a61cd79a03675c45e348edf60240d27dde6
treee309413ad4e343fff8f9d95090c8406d09280b04
parentf54149b920838d6ee2844d8659c81fa4d96d15b9
perf mem: Fix error on hybrid related to availability of mem event in a PMU

[ Upstream commit a4320085a6c694326dd8db46f563d52d1a826f07 ]

The below error can be triggered on a hybrid machine.

 $ perf mem record -t load sleep 1
 event syntax error: 'breakpoint/mem-loads,ldlat=30/P'
                                \___ Bad event or PMU

 Unable to find PMU or event on a PMU of 'breakpoint'

In the perf_mem_events__record_args(), the current perf never checks the
availability of a mem event on a given PMU. All the PMUs will be added
to the perf mem event list. Perf errors out for the unsupported PMU.

Extend perf_mem_event__supported() and take a PMU into account. Check
the mem event for each PMU before adding it to the perf mem event list.

Optimize the perf_mem_events__init() a little bit. The function is to
check whether the mem events are supported in the system. It doesn't
need to scan all PMUs. Just return with the first supported PMU is good
enough.

Fixes: 5752c20f3787c9bc ("perf mem: Scan all PMUs instead of just core ones")
Reported-by: Ammy Yi <ammy.yi@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Ammy Yi <ammy.yi@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20231128203940.3964287-1-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tools/perf/util/mem-events.c