On Thu, Dec 22, 2022 at 04:03:24PM +0000, James Clark wrote:
From: German Gomez german.gomez@arm.com
Add a utility function perf_pmu__file_exists() to check if a given pmu file exists in the sysfs filesystem.
Signed-off-by: German Gomez german.gomez@arm.com Signed-off-by: James Clark james.clark@arm.com
tools/perf/util/pmu.c | 14 ++++++++++++++ tools/perf/util/pmu.h | 2 ++ 2 files changed, 16 insertions(+)
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c index 15b852b3c401..b72b2d892949 100644 --- a/tools/perf/util/pmu.c +++ b/tools/perf/util/pmu.c @@ -1739,6 +1739,20 @@ int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt, return ret; } +bool perf_pmu__file_exists(struct perf_pmu *pmu, const char *name) +{
- char path[PATH_MAX];
- struct stat statbuf;
- if (!perf_pmu__pathname_scnprintf(path, PATH_MAX, pmu->name, name))
return false;- if (!file_available(path))
return false;- return stat(path, &statbuf) == 0;
Can we simply return the returned value from file_available() and skip calling stat()? Because file_available() invokes access() to detect if a file is existed or not, so here calling stat() is redundant.
Thanks, Leo
+}
static int perf_pmu__new_caps(struct list_head *list, char *name, char *value) { struct perf_pmu_caps *caps = zalloc(sizeof(*caps)); diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h index 8f39e2d17fb1..c1d138fe9602 100644 --- a/tools/perf/util/pmu.h +++ b/tools/perf/util/pmu.h @@ -230,6 +230,8 @@ bool pmu_have_event(const char *pname, const char *name); int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt, ...) __scanf(3, 4); +bool perf_pmu__file_exists(struct perf_pmu *pmu, const char *name);
int perf_pmu__test(void); struct perf_event_attr *perf_pmu__get_default_config(struct perf_pmu *pmu); -- 2.25.1