Re: [PATCH v2] sched: fix first task of a task group is attached twice

From: Vincent Guittot
Date: Thu May 26 2016 - 04:27:23 EST


On 26 May 2016 at 00:38, Yuyang Du <yuyang.du@xxxxxxxxx> wrote:
> On Wed, May 25, 2016 at 05:01:11PM +0200, Vincent Guittot wrote:
>> The cfs_rq->avg.last_update_time is initialize to 0 with the main effect
>> that the 1st sched_entity that will be attached, will keep its
>> last_update_time set to 0 and will attached once again during the
>> enqueue.
>> Initialize cfs_rq->avg.last_update_time to 1 instead.
>
> Actually, the first time (attach_task_cfs_rq()) is called even way
> before init_entity_runnable_average(), no?

maybe there is an issue during the fork of a task too
This patch is about the init of the sched_avg of a task group. The
problem happens when the 1st task is moved the group but it's not
about the fork of a task