[PATCH v2 2/6] perf sched timehist: Introduce struct idle_time_data

Namhyung Kim
2016-12-08T14:50:21Z

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>
---
tools/perf/builtin-sched.c | 37 +++++++++++++++++++++++++++++++++----
1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 46aa4705f321..6f0687dd392d 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;
}
}

--
2.10.1