From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756658Ab1EXNu6 (ORCPT ); Tue, 24 May 2011 09:50:58 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:52274 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754836Ab1EXNu5 (ORCPT ); Tue, 24 May 2011 09:50:57 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=PJaZ55HdPcnpcblMIk5I0js0VR4SC54rh93FnCQi159QlLz79RxR4W7+CGkMoSigC9 WatEjy6cS5LsLwTwpZHB2O2M/2OpULQhQSmrUhetPNBf0yDtwuyGW2x6hjcoLlHcHrSU wzuq/CpVHH/BJnebUXhYk4el+UcSzGU0qP7+w= MIME-Version: 1.0 In-Reply-To: <1306244383.1465.59.camel@gandalf.stny.rr.com> References: <1306244383.1465.59.camel@gandalf.stny.rr.com> Date: Tue, 24 May 2011 21:50:56 +0800 Message-ID: Subject: Re: [PATCH] sched: fix need_resched() when checking peempt From: Hillf Danton To: Steven Rostedt Cc: LKML , Ingo Molnar , Peter Zijlstra , Mike Galbraith , Yong Zhang Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 24, 2011 at 9:39 PM, Steven Rostedt wrote: > On Tue, 2011-05-24 at 21:27 +0800, Hillf Danton wrote: >> When checking if current task could be preempted by a newly woken task, >> further check could be bypassed if the current thread is different from >> the current task of run-queue, and it is corrected accordingly. > > Ug, that change log is an obfuscated mess. But looking at the actual > patch, I figured what you wanted to say. How about this: > > ---- > The RT preempt check tests the wrong task if NEED_RESCHED is set. It > currently checks the local CPU task. It is suppose to check the task > that is running on the run queue we are about to wake another task on. > ---- > Thanks, it is great changelog:) Hillf