[PATCH v3 6/7] sched, rt: support sched_stat_runtime tracepoint for RT sched class

From: Yafang Shao
Date: Tue Aug 24 2021 - 07:30:34 EST

The runtime of a RT task has already been there, so we only need to
add a tracepoint.

One difference between fair task and RT task is that there is no vruntime
in RT task. To reuse the sched_stat_runtime tracepoint, '0' is passed as
vruntime for RT task.

The output of this tracepoint for RT task as follows,
stress-9748 [039] d.h. 113.519352: sched_stat_runtime: comm=stress pid=9748 runtime=997573 [ns] vruntime=0 [ns]
stress-9748 [039] d.h. 113.520352: sched_stat_runtime: comm=stress pid=9748 runtime=997627 [ns] vruntime=0 [ns]
stress-9748 [039] d.h. 113.521352: sched_stat_runtime: comm=stress pid=9748 runtime=998203 [ns] vruntime=0 [ns]

Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Alison Chaiken <achaiken@xxxxxxxxxxx>
kernel/sched/rt.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 95a7c3ad2dc3..5d251112e51c 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1012,6 +1012,8 @@ static void update_curr_rt(struct rq *rq)
max(curr->stats.exec_max, delta_exec));

+ trace_sched_stat_runtime(curr, delta_exec, 0);
curr->se.sum_exec_runtime += delta_exec;
account_group_exec_runtime(curr, delta_exec);