From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932450AbcELTuw (ORCPT ); Thu, 12 May 2016 15:50:52 -0400 Received: from mail-wm0-f46.google.com ([74.125.82.46]:38344 "EHLO mail-wm0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932489AbcELTuC (ORCPT ); Thu, 12 May 2016 15:50:02 -0400 From: Matt Fleming To: Peter Zijlstra , Ingo Molnar Cc: linux-kernel@vger.kernel.org, Byungchul Park , Frederic Weisbecker , Luca Abeni , "Rafael J . Wysocki" , Rik van Riel , Thomas Gleixner , Wanpeng Li , Yuyang Du , Mel Gorman , Mike Galbraith , Matt Fleming Subject: [RFC][PATCH 3/5] sched/core: Reset RQCF_ACT_SKIP before unpinning rq->lock Date: Thu, 12 May 2016 20:49:51 +0100 Message-Id: <1463082593-27777-4-git-send-email-matt@codeblueprint.co.uk> X-Mailer: git-send-email 2.7.3 In-Reply-To: <1463082593-27777-1-git-send-email-matt@codeblueprint.co.uk> References: <1463082593-27777-1-git-send-email-matt@codeblueprint.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org rq_clock() is called from sched_info_{depart,arrive}() after resetting RQCF_ACT_SKIP but prior to a call to update_rq_clock(). In preparation for pending patches that check whether the rq clock has been updated inside of a pin context before rq_clock() is called, move the reset of rq->clock_skip_update immediately before unpinning the rq lock. This will avoid the new warnings which check if update_rq_clock() is being actively skipped. Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Mike Galbraith Cc: Mel Gorman Cc: Thomas Gleixner Signed-off-by: Matt Fleming --- kernel/sched/core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index dfdd8c3c083b..d2112c268fd1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2824,6 +2824,9 @@ context_switch(struct rq *rq, struct task_struct *prev, prev->active_mm = NULL; rq->prev_mm = oldmm; } + + rq->clock_skip_update = 0; + /* * Since the runqueue lock will be released by the next * task (which is an invalid locking op but in the case @@ -3316,7 +3319,6 @@ static void __sched notrace __schedule(bool preempt) next = pick_next_task(rq, prev, &rf); clear_tsk_need_resched(prev); clear_preempt_need_resched(); - rq->clock_skip_update = 0; if (likely(prev != next)) { rq->nr_switches++; @@ -3326,6 +3328,7 @@ static void __sched notrace __schedule(bool preempt) trace_sched_switch(preempt, prev, next); rq = context_switch(rq, prev, next, &rf); /* unlocks the rq */ } else { + rq->clock_skip_update = 0; rq_unpin_lock(rq, &rf); raw_spin_unlock_irq(&rq->lock); } -- 2.7.3