On Thu, 09 Jun, at 07:15:53AM, Yuyang Du wrote:
> Newly forked task has not been enqueued, so should not be removed from
> cfs_rq in task_move_group_fair(). To do so, we identify newly forked
> tasks by their sched_avg's last_update_time in detach_entity_load_avg().
>
> Signed-off-by: Yuyang Du <[email protected]>
> ---
> kernel/sched/fair.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 6e870c6..e0f219b 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -2943,6 +2943,10 @@ static inline void attach_entity_load_avg(struct
> cfs_rq *cfs_rq, struct sched_en
>
> static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct
> sched_entity *se)
> {
> + /* Newly forked tasks are not attached yet. */
> + if (!se->avg.last_update_time)
> + return;
> +
Now that we no longer have the @fork parameter to provide context,
this comment would benefit from some expansion. What about something
like this,
/*
* Newly forked tasks that are being moved between groups
* haven't been enqueued anywhere yet, and don't need detaching.
*/
?
