Re: [patch 01/15] sched: (fixlet) dont update shares twice on on_rqparent

[Hidetoshi Seto]

(2011/05/03 18:28), Paul Turner wrote:
> In dequeue_task_fair() we bail on dequeue when we encounter a parenting entity
> with additional weight.  However, we perform a double shares update on this
> entity since we continue the shares update traversal from that point, despite
> dequeue_entity() having already updated its queuing cfs_rq.
> 
> Avoid this by starting from the parent when we resume.
> 
> Signed-off-by: Paul Turner <pjt@xxxxxxxxxx>
> ---
>  kernel/sched_fair.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> Index: tip/kernel/sched_fair.c
> ===================================================================
> --- tip.orig/kernel/sched_fair.c
> +++ tip/kernel/sched_fair.c
> @@ -1355,8 +1355,10 @@ static void dequeue_task_fair(struct rq 
>  		dequeue_entity(cfs_rq, se, flags);
>  
>  		/* Don't dequeue parent if it has other entities besides us */
> -		if (cfs_rq->load.weight)
> +		if (cfs_rq->load.weight) {
> +			se = parent_entity(se);
>  			break;
> +		}
>  		flags |= DEQUEUE_SLEEP;
>  	}
>  

Reviewed-by: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx>

This small fixlet can stand alone.
Peter, how about getting this into git tree first?


Thanks,
H.Seto

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