From 7d4bdab5a441772bfc757d7f9eea9465ec5de0ec Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Thu, 31 Jul 2014 09:00:50 +0300 Subject: [PATCH] perf tools: Add perf_pmu__scan_file() Add a function to scan a sysfs file within the pmu device directory. This will be used to read capability values from the PMU 'caps' subdirectory. Signed-off-by: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1406786474-9306-8-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/pmu.c | 37 +++++++++++++++++++++++++++++++++++++ tools/perf/util/pmu.h | 3 +++ 2 files changed, 40 insertions(+) diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c index 438bb261f391..22a4ad5a927a 100644 --- a/tools/perf/util/pmu.c +++ b/tools/perf/util/pmu.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include #include @@ -804,3 +805,39 @@ bool pmu_have_event(const char *pname, const char *name) } return false; } + +static FILE *perf_pmu__open_file(struct perf_pmu *pmu, const char *name) +{ + struct stat st; + char path[PATH_MAX]; + const char *sysfs; + + sysfs = sysfs__mountpoint(); + if (!sysfs) + return NULL; + + snprintf(path, PATH_MAX, + "%s" EVENT_SOURCE_DEVICE_PATH "%s/%s", sysfs, pmu->name, name); + + if (stat(path, &st) < 0) + return NULL; + + return fopen(path, "r"); +} + +int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt, + ...) +{ + va_list args; + FILE *file; + int ret = EOF; + + va_start(args, fmt); + file = perf_pmu__open_file(pmu, name); + if (file) { + ret = vfscanf(file, fmt, args); + fclose(file); + } + va_end(args); + return ret; +} diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h index 413b9a63c38d..0f5c0a88fdc8 100644 --- a/tools/perf/util/pmu.h +++ b/tools/perf/util/pmu.h @@ -49,6 +49,9 @@ struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu); void print_pmu_events(const char *event_glob, bool name_only); 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, + ...) __attribute__((format(scanf, 3, 4))); + int perf_pmu__test(void); struct perf_event_attr *perf_pmu__get_default_config(struct perf_pmu *pmu); -- 2.39.5