lkml.org 
[lkml]   [2016]   [Jun]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v5 4/5] sched/fair: Skip detach sched avgs for new task when changing task groups
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 <yuyang.du@intel.com>
> ---
> 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.
*/

?

\
 
 \ /
  Last update: 2016-06-14 14:21    [W:1.163 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site