perf sched timehist: Introduce struct idle_time_data

The struct idle_time_data is to keep idle stats with callchains entering
to the idle task.  The normal thread_runtime calculation is done
transparently since it extends the struct thread_runtime.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-3-namhyung@kernel.org
[ Align struct field names ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 33 insertions, 4 deletions

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 966eddce1609..e108b0f6a246 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -230,6 +230,15 @@ struct evsel_runtime {
         u32 ncpu;       /* highest cpu slot allocated */
 };
 
+/* per cpu idle time data */
+struct idle_thread_runtime {
+        struct thread_runtime   tr;
+        struct thread           *last_thread;
+        struct rb_root          sorted_root;
+        struct callchain_root   callchain;
+        struct callchain_cursor cursor;
+};
+
 /* track idle times per cpu */
 static struct thread **idle_threads;
 static int idle_max_cpu;
@@ -1997,13 +2006,31 @@ static void save_task_callchain(struct perf_sched *sched,
         }
 }
 
+static int init_idle_thread(struct thread *thread)
+{
+        struct idle_thread_runtime *itr;
+
+        thread__set_comm(thread, idle_comm, 0);
+
+        itr = zalloc(sizeof(*itr));
+        if (itr == NULL)
+                return -ENOMEM;
+
+        init_stats(&itr->tr.run_stats);
+        callchain_init(&itr->callchain);
+        callchain_cursor_reset(&itr->cursor);
+        thread__set_priv(thread, itr);
+
+        return 0;
+}
+
 /*
  * Track idle stats per cpu by maintaining a local thread
  * struct for the idle task on each cpu.
  */
 static int init_idle_threads(int ncpu)
 {
-        int i;
+        int i, ret;
 
         idle_threads = zalloc(ncpu * sizeof(struct thread *));
         if (!idle_threads)
@@ -2017,7 +2044,9 @@ static int init_idle_threads(int ncpu)
                 if (idle_threads[i] == NULL)
                         return -ENOMEM;
 
-                thread__set_comm(idle_threads[i], idle_comm, 0);
+                ret = init_idle_thread(idle_threads[i]);
+                if (ret < 0)
+                        return ret;
         }
 
         return 0;
@@ -2064,8 +2093,8 @@ static struct thread *get_idle_thread(int cpu)
                 idle_threads[cpu] = thread__new(0, 0);
 
                 if (idle_threads[cpu]) {
-                        idle_threads[cpu]->tid = 0;
-                        thread__set_comm(idle_threads[cpu], idle_comm, 0);
+                        if (init_idle_thread(idle_threads[cpu]) < 0)
+                                return NULL;
                 }
         }