From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758116Ab1I3DzJ (ORCPT ); Thu, 29 Sep 2011 23:55:09 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:47180 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757463Ab1I3DzF (ORCPT ); Thu, 29 Sep 2011 23:55:05 -0400 Date: Thu, 29 Sep 2011 20:55:01 -0700 From: Tejun Heo To: Steven Rostedt Cc: LKML , Peter Zijlstra , Thomas Gleixner Subject: Re: [PATCH] sched/kthread: Complain loudly when others violate our flags Message-ID: <20110930035501.GG10425@mtj.dyndns.org> References: <1317158254.26514.55.camel@gandalf.stny.rr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1317158254.26514.55.camel@gandalf.stny.rr.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 27, 2011 at 05:17:34PM -0400, Steven Rostedt wrote: > For convenience and optimization, we are going to use the task's flag > PF_THREAD_BOUND as a way to know if a task is bound to a CPU or not. As > that is what the flag means. And I'm not sure this is a very good idea. Until now, PF_THREAD_BOUND meant "this task is explicitly bound to the current affinity (whatever it is) and thus it shouldn't be manipulated by third party". The suggested change makes the flag much less orthogonal and useful. How much of convenience and optimization are we talking about? Thanks. -- tejun