perf evlist: Introduce side band thread

[thirdparty/kernel/linux.git] / tools / perf / util / evlist.c

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index ed20f4379956594a908299f08c9d2ef4ac140dc2..ec78e93085ded81aa9def49640b48495b93ead7c 100644 (file)
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -19,6 +19,7 @@
 #include "debug.h"
 #include "units.h"
 #include "asm/bug.h"
+#include "bpf-event.h"
 #include <signal.h>
 #include <unistd.h>
 
@@ -1856,3 +1857,121 @@ struct perf_evsel *perf_evlist__reset_weak_group(struct perf_evlist *evsel_list,
        }
        return leader;
 }
+
+int perf_evlist__add_sb_event(struct perf_evlist **evlist,
+                             struct perf_event_attr *attr,
+                             perf_evsel__sb_cb_t cb,
+                             void *data)
+{
+       struct perf_evsel *evsel;
+       bool new_evlist = (*evlist) == NULL;
+
+       if (*evlist == NULL)
+               *evlist = perf_evlist__new();
+       if (*evlist == NULL)
+               return -1;
+
+       if (!attr->sample_id_all) {
+               pr_warning("enabling sample_id_all for all side band events\n");
+               attr->sample_id_all = 1;
+       }
+
+       evsel = perf_evsel__new_idx(attr, (*evlist)->nr_entries);
+       if (!evsel)
+               goto out_err;
+
+       evsel->side_band.cb = cb;
+       evsel->side_band.data = data;
+       perf_evlist__add(*evlist, evsel);
+       return 0;
+
+out_err:
+       if (new_evlist) {
+               perf_evlist__delete(*evlist);
+               *evlist = NULL;
+       }
+       return -1;
+}
+
+static void *perf_evlist__poll_thread(void *arg)
+{
+       struct perf_evlist *evlist = arg;
+       bool draining = false;
+       int i;
+
+       while (draining || !(evlist->thread.done)) {
+               if (draining)
+                       draining = false;
+               else if (evlist->thread.done)
+                       draining = true;
+
+               if (!draining)
+                       perf_evlist__poll(evlist, 1000);
+
+               for (i = 0; i < evlist->nr_mmaps; i++) {
+                       struct perf_mmap *map = &evlist->mmap[i];
+                       union perf_event *event;
+
+                       if (perf_mmap__read_init(map))
+                               continue;
+                       while ((event = perf_mmap__read_event(map)) != NULL) {
+                               struct perf_evsel *evsel = perf_evlist__event2evsel(evlist, event);
+
+                               if (evsel && evsel->side_band.cb)
+                                       evsel->side_band.cb(event, evsel->side_band.data);
+                               else
+                                       pr_warning("cannot locate proper evsel for the side band event\n");
+
+                               perf_mmap__consume(map);
+                       }
+                       perf_mmap__read_done(map);
+               }
+       }
+       return NULL;
+}
+
+int perf_evlist__start_sb_thread(struct perf_evlist *evlist,
+                                struct target *target)
+{
+       struct perf_evsel *counter;
+
+       if (!evlist)
+               return 0;
+
+       if (perf_evlist__create_maps(evlist, target))
+               goto out_delete_evlist;
+
+       evlist__for_each_entry(evlist, counter) {
+               if (perf_evsel__open(counter, evlist->cpus,
+                                    evlist->threads) < 0)
+                       goto out_delete_evlist;
+       }
+
+       if (perf_evlist__mmap(evlist, UINT_MAX))
+               goto out_delete_evlist;
+
+       evlist__for_each_entry(evlist, counter) {
+               if (perf_evsel__enable(counter))
+                       goto out_delete_evlist;
+       }
+
+       evlist->thread.done = 0;
+       if (pthread_create(&evlist->thread.th, NULL, perf_evlist__poll_thread, evlist))
+               goto out_delete_evlist;
+
+       return 0;
+
+out_delete_evlist:
+       perf_evlist__delete(evlist);
+       evlist = NULL;
+       return -1;
+}
+
+void perf_evlist__stop_sb_thread(struct perf_evlist *evlist)
+{
+       if (!evlist)
+               return;
+       evlist->thread.done = 1;
+       pthread_join(evlist->thread.th, NULL);
+       perf_evlist__delete(evlist);
+}