perf arm: Workaround ARM PMUs cpu maps having offline cpus
authorIan Rogers <irogers@google.com>
Fri, 7 Jun 2024 06:53:43 +0000 (23:53 -0700)
committerNamhyung Kim <namhyung@kernel.org>
Fri, 21 Jun 2024 22:50:29 +0000 (15:50 -0700)
commit5518063fcb2e022411c1112b1b9b069e68380bbb
tree6005fc6b19042f3e72bb7b20f306b270cf464230
parent3612ca8e2935c4c142d99e33b8effa7045ce32b5
perf arm: Workaround ARM PMUs cpu maps having offline cpus

When PMUs have a cpu map in the 'cpus' or 'cpumask' file, perf will
try to open events on those CPUs. ARM doesn't remove offline CPUs
meaning taking a CPU offline will cause perf commands to fail unless a
CPU map is passed on the command line.

More context in:
https://lore.kernel.org/lkml/20240603092812.46616-1-yangyicong@huawei.com/

Reported-by: Yicong Yang <yangyicong@huawei.com>
Closes: https://lore.kernel.org/lkml/20240603092812.46616-2-yangyicong@huawei.com/
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Tested-by: Leo Yan <leo.yan@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: linux-arm-kernel@lists.infradead.org
Cc: coresight@lists.linaro.org
Cc: John Garry <john.g.garry@oracle.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240607065343.695369-1-irogers@google.com
tools/perf/arch/arm/util/pmu.c