From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753164AbcFOGSL (ORCPT ); Wed, 15 Jun 2016 02:18:11 -0400 Received: from mga14.intel.com ([192.55.52.115]:44070 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751529AbcFOGSJ (ORCPT ); Wed, 15 Jun 2016 02:18:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,474,1459839600"; d="scan'208";a="987738258" From: Yuyang Du To: peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org Cc: umgwanakikbuti@gmail.com, bsegall@google.com, pjt@google.com, morten.rasmussen@arm.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, matt@codeblueprint.co.uk, Yuyang Du Subject: [PATCH v6 3/4] sched/fair: Skip detach sched avgs for new task when changing task groups Date: Wed, 15 Jun 2016 06:21:09 +0800 Message-Id: <1465942870-28419-4-git-send-email-yuyang.du@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1465942870-28419-1-git-send-email-yuyang.du@intel.com> References: <1465942870-28419-1-git-send-email-yuyang.du@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 if their sum_exec_runtime is 0, an existing heuristic as per vruntime_normalized(). In addition to that, uniformly use this test in remove_entity_load_avg(). Signed-off-by: Yuyang Du --- kernel/sched/fair.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 3a28922..e9f2754 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->sum_exec_runtime) + return; + __update_load_avg(cfs_rq->avg.last_update_time, cpu_of(rq_of(cfs_rq)), &se->avg, se->on_rq * scale_load_down(se->load.weight), cfs_rq->curr == se, NULL); @@ -3033,7 +3037,7 @@ void remove_entity_load_avg(struct sched_entity *se) * Newly created task or never used group entity should not be removed * from its (source) cfs_rq */ - if (se->avg.last_update_time == 0) + if (!se->sum_exec_runtime) return; last_update_time = cfs_rq_last_update_time(cfs_rq); -- 1.7.9.5