From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757195AbdDFJqo convert rfc822-to-8bit (ORCPT ); Thu, 6 Apr 2017 05:46:44 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:36193 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757144AbdDFJqf (ORCPT ); Thu, 6 Apr 2017 05:46:35 -0400 Date: Thu, 6 Apr 2017 11:46:33 +0200 From: Sebastian Andrzej Siewior To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , Mike Galbraith , Ingo Molnar , "Rafael J . Wysocki" Subject: Re: [RFC PATCH] kernel: sched: Provide a pointer to the valid CPU mask Message-ID: <20170406094626.a42cq66ezgq4lohh@linutronix.de> References: <20170404184202.20376-1-bigeasy@linutronix.de> <20170406093224.q3tunb6gdx5a6flr@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20170406093224.q3tunb6gdx5a6flr@hirez.programming.kicks-ass.net> User-Agent: NeoMutt/20170306 (1.8.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017-04-06 11:32:24 [+0200], Peter Zijlstra wrote: > On Tue, Apr 04, 2017 at 08:42:02PM +0200, Sebastian Andrzej Siewior wrote: > > While converting the existing users I tried to stick with the rules > > above however… well mostly CPUFREQ tries to temporary switch the CPU > > mask to do something on a certain CPU and then switches the mask back it > > its original value. > > > There's a bunch of that through ancient and rotten parts of the kernel. > All those sites are broken. > > Nothing stops userspace from setting a different affinity right after > the kernel does for those threads. Good. So you are saying I should convert them to something like queue_work_on()? Sebastian