Merge tag 'mac80211-for-john-2014-11-18' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / tools / perf / util / evlist.c

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 3cebc9a..3c9e77d 100644 (file)
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1003,6 +1003,7 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
 
 out_delete_threads:
        thread_map__delete(evlist->threads);
+       evlist->threads = NULL;
        return -1;
 }
 
@@ -1175,11 +1176,51 @@ void perf_evlist__close(struct perf_evlist *evlist)
        }
 }
 
+static int perf_evlist__create_syswide_maps(struct perf_evlist *evlist)
+{
+       int err = -ENOMEM;
+
+       /*
+        * Try reading /sys/devices/system/cpu/online to get
+        * an all cpus map.
+        *
+        * FIXME: -ENOMEM is the best we can do here, the cpu_map
+        * code needs an overhaul to properly forward the
+        * error, and we may not want to do that fallback to a
+        * default cpu identity map :-\
+        */
+       evlist->cpus = cpu_map__new(NULL);
+       if (evlist->cpus == NULL)
+               goto out;
+
+       evlist->threads = thread_map__new_dummy();
+       if (evlist->threads == NULL)
+               goto out_free_cpus;
+
+       err = 0;
+out:
+       return err;
+out_free_cpus:
+       cpu_map__delete(evlist->cpus);
+       evlist->cpus = NULL;
+       goto out;
+}
+
 int perf_evlist__open(struct perf_evlist *evlist)
 {
        struct perf_evsel *evsel;
        int err;
 
+       /*
+        * Default: one fd per CPU, all threads, aka systemwide
+        * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
+        */
+       if (evlist->threads == NULL && evlist->cpus == NULL) {
+               err = perf_evlist__create_syswide_maps(evlist);
+               if (err < 0)
+                       goto out_err;
+       }
+
        perf_evlist__update_id_pos(evlist);
 
        evlist__for_each(evlist, evsel) {
@@ -1276,8 +1317,14 @@ int perf_evlist__prepare_workload(struct perf_evlist *evlist, struct target *tar
                sigaction(SIGUSR1, &act, NULL);
        }
 
-       if (target__none(target))
+       if (target__none(target)) {
+               if (evlist->threads == NULL) {
+                       fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
+                               __func__, __LINE__);
+                       goto out_close_pipes;
+               }
                evlist->threads->map[0] = evlist->workload.pid;
+       }
 
        close(child_ready_pipe[1]);
        close(go_pipe[0]);