perf stat: Check PMU cpumask file

If user doesn't explicitly specify CPU list, perf-stat only collects
events on CPUs listed in the PMU cpumask file.

Signed-off-by: "Yah, Zheng" <zheng.z.yan@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1347263631-23175-3-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

6 files changed, 62 insertions, 12 deletions

diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c
index adc72f09914..2b32ffa9ebd 100644
--- a/tools/perf/util/cpumap.c
+++ b/tools/perf/util/cpumap.c
@@ -38,24 +38,19 @@ static struct cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
         return cpus;
 }
 
-static struct cpu_map *cpu_map__read_all_cpu_map(void)
+struct cpu_map *cpu_map__read(FILE *file)
 {
         struct cpu_map *cpus = NULL;
-        FILE *onlnf;
         int nr_cpus = 0;
         int *tmp_cpus = NULL, *tmp;
         int max_entries = 0;
         int n, cpu, prev;
         char sep;
 
-        onlnf = fopen("/sys/devices/system/cpu/online", "r");
-        if (!onlnf)
-                return cpu_map__default_new();
-
         sep = 0;
         prev = -1;
         for (;;) {
-                n = fscanf(onlnf, "%u%c", &cpu, &sep);
+                n = fscanf(file, "%u%c", &cpu, &sep);
                 if (n <= 0)
                         break;
                 if (prev >= 0) {
@@ -95,6 +90,19 @@ static struct cpu_map *cpu_map__read_all_cpu_map(void)
                 cpus = cpu_map__default_new();
 out_free_tmp:
         free(tmp_cpus);
+        return cpus;
+}
+
+static struct cpu_map *cpu_map__read_all_cpu_map(void)
+{
+        struct cpu_map *cpus = NULL;
+        FILE *onlnf;
+
+        onlnf = fopen("/sys/devices/system/cpu/online", "r");
+        if (!onlnf)
+                return cpu_map__default_new();
+
+        cpus = cpu_map__read(onlnf);
         fclose(onlnf);
         return cpus;
 }
diff --git a/tools/perf/util/cpumap.h b/tools/perf/util/cpumap.h
index c41518573c6..17b5264f643 100644
--- a/tools/perf/util/cpumap.h
+++ b/tools/perf/util/cpumap.h
@@ -11,7 +11,7 @@ struct cpu_map {
 struct cpu_map *cpu_map__new(const char *cpu_list);
 struct cpu_map *cpu_map__dummy_new(void);
 void cpu_map__delete(struct cpu_map *map);
-
+struct cpu_map *cpu_map__read(FILE *file);
 size_t cpu_map__fprintf(struct cpu_map *map, FILE *fp);
 
 #endif /* __PERF_CPUMAP_H */
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index dc40fe32210..93876bad2e5 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -66,6 +66,7 @@ struct perf_evsel {
                 void            *func;
                 void            *data;
         } handler;
+        struct cpu_map          *cpus;
         unsigned int            sample_size;
         bool                    supported;
         /* parse modifier helper */
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 44afcf40f79..bf5d033ee1b 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -239,8 +239,11 @@ const char *event_type(int type)
         return "unknown";
 }
 
-static int add_event(struct list_head **_list, int *idx,
-                     struct perf_event_attr *attr, char *name)
+
+
+static int __add_event(struct list_head **_list, int *idx,
+                       struct perf_event_attr *attr,
+                       char *name, struct cpu_map *cpus)
 {
         struct perf_evsel *evsel;
         struct list_head *list = *_list;
@@ -260,6 +263,7 @@ static int add_event(struct list_head **_list, int *idx,
                 return -ENOMEM;
         }
 
+        evsel->cpus = cpus;
         if (name)
                 evsel->name = strdup(name);
         list_add_tail(&evsel->node, list);
@@ -267,6 +271,12 @@ static int add_event(struct list_head **_list, int *idx,
         return 0;
 }
 
+static int add_event(struct list_head **_list, int *idx,
+                     struct perf_event_attr *attr, char *name)
+{
+        return __add_event(_list, idx, attr, name, NULL);
+}
+
 static int parse_aliases(char *str, const char *names[][PERF_EVSEL__MAX_ALIASES], int size)
 {
         int i, j;
@@ -607,8 +617,8 @@ int parse_events_add_pmu(struct list_head **list, int *idx,
         if (perf_pmu__config(pmu, &attr, head_config))
                 return -EINVAL;
 
-        return add_event(list, idx, &attr,
-                         pmu_event_name(head_config));
+        return __add_event(list, idx, &attr, pmu_event_name(head_config),
+                           pmu->cpus);
 }
 
 int parse_events__modifier_group(struct list_head *list,
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 6631d828db3..8a2229da594 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -9,6 +9,7 @@
 #include "util.h"
 #include "pmu.h"
 #include "parse-events.h"
+#include "cpumap.h"
 
 #define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"
 
@@ -253,6 +254,33 @@ static void pmu_read_sysfs(void)
         closedir(dir);
 }
 
+static struct cpu_map *pmu_cpumask(char *name)
+{
+        struct stat st;
+        char path[PATH_MAX];
+        const char *sysfs;
+        FILE *file;
+        struct cpu_map *cpus;
+
+        sysfs = sysfs_find_mountpoint();
+        if (!sysfs)
+                return NULL;
+
+        snprintf(path, PATH_MAX,
+                 "%s/bus/event_source/devices/%s/cpumask", sysfs, name);
+
+        if (stat(path, &st) < 0)
+                return NULL;
+
+        file = fopen(path, "r");
+        if (!file)
+                return NULL;
+
+        cpus = cpu_map__read(file);
+        fclose(file);
+        return cpus;
+}
+
 static struct perf_pmu *pmu_lookup(char *name)
 {
         struct perf_pmu *pmu;
@@ -275,6 +303,8 @@ static struct perf_pmu *pmu_lookup(char *name)
         if (!pmu)
                 return NULL;
 
+        pmu->cpus = pmu_cpumask(name);
+
         pmu_aliases(name, &aliases);
 
         INIT_LIST_HEAD(&pmu->format);
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index 47f68d3cc5d..53c7794fc4b 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -28,6 +28,7 @@ struct perf_pmu__alias {
 struct perf_pmu {
         char *name;
         __u32 type;
+        struct cpu_map *cpus;
         struct list_head format;
         struct list_head aliases;
         struct list_head list;