Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750805AbaLOL5G (ORCPT ); Mon, 15 Dec 2014 06:57:06 -0500 Received: from relay.parallels.com ([195.214.232.42]:48950 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750704AbaLOL5C (ORCPT ); Mon, 15 Dec 2014 06:57:02 -0500 Message-ID: <1418644618.6074.13.camel@tkhai> Subject: [PATCH] sched/fair: Fix sched_entity::avg::decay_count initialization From: Kirill Tkhai To: CC: Peter Zijlstra , Ingo Molnar , Kirill Tkhai Date: Mon, 15 Dec 2014 14:56:58 +0300 Organization: Parallels Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.8.5-2+b3 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.30.26.172] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Child has the same decay_count as parent. If it's not zero, we add it to parent's cfs_rq->removed_load: wake_up_new_task()->set_task_cpu()->migrate_task_rq_fair(). Child's load is a just garbade after copying of parent, it hasn't been on cfs_rq yet, and it must not be added to cfs_rq::removed_load in migrate_task_rq_fair(). The patch moves sched_entity::avg::decay_count intialization in sched_fork(). So, migrate_task_rq_fair() does not change removed_load. Signed-off-by: Kirill Tkhai --- kernel/sched/core.c | 1 + kernel/sched/fair.c | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bb398c0..2894b69 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1832,6 +1832,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) p->se.prev_sum_exec_runtime = 0; p->se.nr_migrations = 0; p->se.vruntime = 0; + p->se.avg.decay_count = 0; INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_SCHEDSTATS diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index df2cdf7..5f3b5a7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -676,7 +676,6 @@ void init_task_runnable_average(struct task_struct *p) { u32 slice; - p->se.avg.decay_count = 0; slice = sched_slice(task_cfs_rq(p), &p->se) >> 10; p->se.avg.runnable_avg_sum = slice; p->se.avg.runnable_avg_period = slice; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/