linux-kernel - Re: [PATCH 1/2] sched/fair: optimization of update_blocked

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 8 Feb 2019 16:40:09 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     Vincent Guittot <vincent.guittot@...aro.org>
Cc:     linux-kernel@...r.kernel.org, mingo@...hat.com, tj@...nel.org,
        sargun@...gun.me, xiexiuqi@...wei.com, xiezhipeng1@...wei.com,
        torvalds@...ux-foundation.org
Subject: Re: [PATCH 1/2] sched/fair: optimization of update_blocked_averages()


Argh head hurts!!

On Wed, Feb 06, 2019 at 05:14:21PM +0100, Vincent Guittot wrote:
> @@ -4438,6 +4450,10 @@ static int tg_unthrottle_up(struct task_group *tg, void *data)
>  		/* adjust cfs_rq_clock_task() */
>  		cfs_rq->throttled_clock_task_time += rq_clock_task(rq) -
>  					     cfs_rq->throttled_clock_task;
> +
> +		/* Add cfs_rq with already running entity in the list */
> +		if (cfs_rq->nr_running >= 1)
> +			list_add_leaf_cfs_rq(cfs_rq);
>  	}
>  
>  	return 0;

Do we want the below to go with the above change?

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 38d4669aa2ef..0bd80a891025 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4536,6 +4536,8 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 	/* update hierarchical throttle state */
 	walk_tg_tree_from(cfs_rq->tg, tg_nop, tg_unthrottle_up, (void *)rq);
 
+	assert_list_leaf_cfs_rq(rq);
+
 	if (!cfs_rq->load.weight)
 		return;