From: Ian Rogers Date: Sat, 19 Jul 2025 03:05:03 +0000 (-0700) Subject: perf parse-events: Warn if a cpu term is unsupported by a CPU X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=62f4512238f5541d864a783cbcd8d95d067a17b3;p=users%2Fjedix%2Flinux-maple.git perf parse-events: Warn if a cpu term is unsupported by a CPU Factor requested CPU warning out of evlist and into evsel. At the end of adding an event, perform the warning check. To avoid repeatedly testing if the cpu_list is empty, add a local variable. ``` $ perf stat -e cpu_atom/cycles,cpu=1/ -a true WARNING: A requested CPU in '1' is not supported by PMU 'cpu_atom' (CPUs 16-27) for event 'cpu_atom/cycles/' Performance counter stats for 'system wide': cpu_atom/cycles/ 0.000781511 seconds time elapsed ``` Reviewed-by: Thomas Falcon Signed-off-by: Ian Rogers Tested-by: James Clark Link: https://lore.kernel.org/r/20250719030517.1990983-2-irogers@google.com Signed-off-by: Namhyung Kim --- diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 995ad5f654d07..80d8387e6b97b 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -2549,20 +2549,7 @@ void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_lis return; evlist__for_each_entry(evlist, pos) { - struct perf_cpu_map *intersect, *to_test, *online = cpu_map__online(); - const struct perf_pmu *pmu = evsel__find_pmu(pos); - - to_test = pmu && pmu->is_core ? pmu->cpus : online; - intersect = perf_cpu_map__intersect(to_test, user_requested_cpus); - if (!perf_cpu_map__equal(intersect, user_requested_cpus)) { - char buf[128]; - - cpu_map__snprint(to_test, buf, sizeof(buf)); - pr_warning("WARNING: A requested CPU in '%s' is not supported by PMU '%s' (CPUs %s) for event '%s'\n", - cpu_list, pmu ? pmu->name : "cpu", buf, evsel__name(pos)); - } - perf_cpu_map__put(intersect); - perf_cpu_map__put(online); + evsel__warn_user_requested_cpus(pos, user_requested_cpus); } perf_cpu_map__put(user_requested_cpus); } diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 3896a04d90af7..d9b6bf78d67b0 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -4091,3 +4091,27 @@ void evsel__uniquify_counter(struct evsel *counter) counter->uniquified_name = false; } } + +void evsel__warn_user_requested_cpus(struct evsel *evsel, struct perf_cpu_map *user_requested_cpus) +{ + struct perf_cpu_map *intersect, *online = NULL; + const struct perf_pmu *pmu = evsel__find_pmu(evsel); + + if (pmu && pmu->is_core) { + intersect = perf_cpu_map__intersect(pmu->cpus, user_requested_cpus); + } else { + online = cpu_map__online(); + intersect = perf_cpu_map__intersect(online, user_requested_cpus); + } + if (!perf_cpu_map__equal(intersect, user_requested_cpus)) { + char buf1[128]; + char buf2[128]; + + cpu_map__snprint(user_requested_cpus, buf1, sizeof(buf1)); + cpu_map__snprint(online ?: pmu->cpus, buf2, sizeof(buf2)); + pr_warning("WARNING: A requested CPU in '%s' is not supported by PMU '%s' (CPUs %s) for event '%s'\n", + buf1, pmu ? pmu->name : "cpu", buf2, evsel__name(evsel)); + } + perf_cpu_map__put(intersect); + perf_cpu_map__put(online); +} diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index b84ee274602d7..cefa8e64c0d5e 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -574,4 +574,6 @@ void evsel__set_config_if_unset(struct perf_pmu *pmu, struct evsel *evsel, bool evsel__is_offcpu_event(struct evsel *evsel); +void evsel__warn_user_requested_cpus(struct evsel *evsel, struct perf_cpu_map *user_requested_cpus); + #endif /* __PERF_EVSEL_H */ diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index a59ae5ca0f894..3fd6cc0c2794c 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -252,6 +252,7 @@ __add_event(struct list_head *list, int *idx, struct evsel *evsel; bool is_pmu_core; struct perf_cpu_map *cpus; + bool has_cpu_list = !perf_cpu_map__is_empty(cpu_list); /* * Ensure the first_wildcard_match's PMU matches that of the new event @@ -276,7 +277,7 @@ __add_event(struct list_head *list, int *idx, if (pmu) { is_pmu_core = pmu->is_core; - cpus = perf_cpu_map__get(perf_cpu_map__is_empty(cpu_list) ? pmu->cpus : cpu_list); + cpus = perf_cpu_map__get(has_cpu_list ? cpu_list : pmu->cpus); perf_pmu__warn_invalid_formats(pmu); if (attr->type == PERF_TYPE_RAW || attr->type >= PERF_TYPE_MAX) { perf_pmu__warn_invalid_config(pmu, attr->config, name, @@ -291,10 +292,10 @@ __add_event(struct list_head *list, int *idx, } else { is_pmu_core = (attr->type == PERF_TYPE_HARDWARE || attr->type == PERF_TYPE_HW_CACHE); - if (perf_cpu_map__is_empty(cpu_list)) - cpus = is_pmu_core ? perf_cpu_map__new_online_cpus() : NULL; - else + if (has_cpu_list) cpus = perf_cpu_map__get(cpu_list); + else + cpus = is_pmu_core ? cpu_map__online() : NULL; } if (init_attr) event_attr_init(attr); @@ -326,6 +327,9 @@ __add_event(struct list_head *list, int *idx, if (list) list_add_tail(&evsel->core.node, list); + if (has_cpu_list) + evsel__warn_user_requested_cpus(evsel, cpu_list); + return evsel; }