From: Ian Rogers irogers@google.com
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 | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/tools/perf/arch/arm/util/pmu.c b/tools/perf/arch/arm/util/pmu.c index 887c8addc491..e10ac550e4e4 100644 --- a/tools/perf/arch/arm/util/pmu.c +++ b/tools/perf/arch/arm/util/pmu.c @@ -11,11 +11,14 @@
#include "arm-spe.h" #include "hisi-ptt.h" +#include "../../../util/cpumap.h" #include "../../../util/pmu.h"
struct perf_event_attr -*perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused) +*perf_pmu__get_default_config(struct perf_pmu *pmu) { + struct perf_cpu_map *intersect; + #ifdef HAVE_AUXTRACE_SUPPORT if (!strcmp(pmu->name, CORESIGHT_ETM_PMU_NAME)) { /* add ETM default config here */ @@ -29,5 +32,10 @@ struct perf_event_attr }
#endif + /* Workaround some ARM PMU's failing to correctly set CPU maps for online processors. */ + intersect = perf_cpu_map__intersect(cpu_map__online(), pmu->cpus); + perf_cpu_map__put(pmu->cpus); + pmu->cpus = intersect; + return NULL; }