From 66ec11919a0f96e936bb731fdbc2851316077d26 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 6 Oct 2017 19:38:22 +0100 Subject: perf pmu: Unbreak perf record for arm/arm64 with events with explicit PMU Currently, perf record is broken on arm/arm64 systems when the PMU is specified explicitly as part of the event, e.g. $ ./perf record -e armv8_cortex_a53/cpu_cycles/u true In such cases, perf record fails to open events unless perf_event_paranoid is set to -1, even if the PMU in question supports mode exclusion. Further, even when perf_event_paranoid is toggled, no samples are recorded. This is an unintended side effect of commit: e3ba76deef23064f ("perf tools: Force uncore events to system wide monitoring) ... which assumes that if a PMU has an associated cpu_map, it is an uncore PMU, and forces events for such PMUs to be system-wide. This is not true for arm/arm64 systems, which can have heterogeneous CPUs. To account for this, multiple CPU PMUs are exposed, each with a "cpus" field under sysfs, which the perf tool parses into a cpu_map. ARM PMUs do not have a "cpumask" file, and only have a "cpus" file. For the gory details as to why, see commit: 7e3fcffe95544010 ("perf pmu: Support alternative sysfs cpumask") Given all of this, we can instead identify uncore PMUs by explicitly checking for a "cpumask" file, and restore arm/arm64 PMU support back to a working state. This patch does so, adding a new perf_pmu::is_uncore field, and splitting the existing cpumask parsing so that it can be reused. Signed-off-by: Mark Rutland Tested-by Will Deacon Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Cc: 4.12+ Fixes: e3ba76deef23064f ("perf tools: Force uncore events to system wide monitoring) Link: http://lkml.kernel.org/r/1507315102-5942-1-git-send-email-mark.rutland@arm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/parse-events.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'tools/perf/util/parse-events.c') diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index f6257fb..39b1596 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -309,10 +309,11 @@ static char *get_config_name(struct list_head *head_terms) static struct perf_evsel * __add_event(struct list_head *list, int *idx, struct perf_event_attr *attr, - char *name, struct cpu_map *cpus, + char *name, struct perf_pmu *pmu, struct list_head *config_terms, bool auto_merge_stats) { struct perf_evsel *evsel; + struct cpu_map *cpus = pmu ? pmu->cpus : NULL; event_attr_init(attr); @@ -323,7 +324,7 @@ __add_event(struct list_head *list, int *idx, (*idx)++; evsel->cpus = cpu_map__get(cpus); evsel->own_cpus = cpu_map__get(cpus); - evsel->system_wide = !!cpus; + evsel->system_wide = pmu ? pmu->is_uncore : false; evsel->auto_merge_stats = auto_merge_stats; if (name) @@ -1233,7 +1234,7 @@ static int __parse_events_add_pmu(struct parse_events_state *parse_state, if (!head_config) { attr.type = pmu->type; - evsel = __add_event(list, &parse_state->idx, &attr, NULL, pmu->cpus, NULL, auto_merge_stats); + evsel = __add_event(list, &parse_state->idx, &attr, NULL, pmu, NULL, auto_merge_stats); return evsel ? 0 : -ENOMEM; } @@ -1254,7 +1255,7 @@ static int __parse_events_add_pmu(struct parse_events_state *parse_state, return -EINVAL; evsel = __add_event(list, &parse_state->idx, &attr, - get_config_name(head_config), pmu->cpus, + get_config_name(head_config), pmu, &config_terms, auto_merge_stats); if (evsel) { evsel->unit = info.unit; -- cgit v1.1