From 14b0fffa25ce4a9ef5d4448b20b80217b2caa0e8 Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Sat, 6 Jul 2024 16:20:35 +0100 Subject: [PATCH] perf mem: Warn if memory events are not supported on all CPUs It is possible that memory events are not supported on all CPUs. Prints a warning by dumping the enabled CPU maps in this case. Signed-off-by: Leo Yan Reviewed-by: James Clark Cc: Suzuki K Poulose Cc: Will Deacon Cc: Mike Leach Cc: Kajol Jain Cc: John Garry Cc: linux-arm-kernel@lists.infradead.org Cc: coresight@lists.linaro.org Link: https://lore.kernel.org/r/20240706152035.86983-3-leo.yan@arm.com Signed-off-by: Namhyung Kim --- tools/perf/util/mem-events.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c index 429079329e48..be048bd02f36 100644 --- a/tools/perf/util/mem-events.c +++ b/tools/perf/util/mem-events.c @@ -8,6 +8,7 @@ #include #include #include +#include "cpumap.h" #include "map_symbol.h" #include "mem-events.h" #include "mem-info.h" @@ -242,6 +243,7 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr) int i = *argv_nr; const char *s; char *copy; + struct perf_cpu_map *cpu_map = NULL; while ((pmu = perf_pmus__scan_mem(pmu)) != NULL) { for (int j = 0; j < PERF_MEM_EVENTS__MAX; j++) { @@ -266,9 +268,21 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr) rec_argv[i++] = "-e"; rec_argv[i++] = copy; + + cpu_map = perf_cpu_map__merge(cpu_map, pmu->cpus); } } + if (cpu_map) { + if (!perf_cpu_map__equal(cpu_map, cpu_map__online())) { + char buf[200]; + + cpu_map__snprint(cpu_map, buf, sizeof(buf)); + pr_warning("Memory events are enabled on a subset of CPUs: %s\n", buf); + } + perf_cpu_map__put(cpu_map); + } + *argv_nr = i; return 0; }