From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH] sched: fix incorrect wait time and wait count statistics Date: Sun, 25 Oct 2015 11:08:50 +0100 Message-ID: <20151025100850.GO2508@worktop.programming.kicks-ass.net> References: <1445750594-14078-1-git-send-email-joonwoop@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from bombadil.infradead.org ([198.137.202.9]:59587 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751183AbbJYKIi (ORCPT ); Sun, 25 Oct 2015 06:08:38 -0400 Content-Disposition: inline In-Reply-To: <1445750594-14078-1-git-send-email-joonwoop@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Joonwoo Park Cc: Ingo Molnar , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org On Sat, Oct 24, 2015 at 10:23:14PM -0700, Joonwoo Park wrote: > At present scheduler resets task's wait start timestamp when the task > migrates to another rq. This misleads scheduler itself into reporting > less wait time than actual by omitting time spent for waiting prior to > migration and also more wait count than actual by counting migration as > wait end event which can be seen by trace or /proc//sched with > CONFIG_SCHEDSTATS=y. > Have you seen: 1de64443d755 ("sched/core: Fix task and run queue sched_info::run_delay inconsistencies") ?