From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753877AbaCRIJc (ORCPT ); Tue, 18 Mar 2014 04:09:32 -0400 Received: from mail-qa0-f48.google.com ([209.85.216.48]:64854 "EHLO mail-qa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751901AbaCRIJ3 (ORCPT ); Tue, 18 Mar 2014 04:09:29 -0400 MIME-Version: 1.0 In-Reply-To: References: <9144e10d7e854a0aa8a673332adec356d81a923c.1393576981.git.viresh.kumar@linaro.org> Date: Tue, 18 Mar 2014 13:39:28 +0530 Message-ID: Subject: Re: [PATCH 2/2] timer: Make sure TIMER_FLAG_MASK bits are free in allocated base From: Viresh Kumar To: Thomas Gleixner , Peter Zijlstra Cc: Lists linaro-kernel , Linux Kernel Mailing List , =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= , Tejun Heo , Ingo Molnar Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11 March 2014 15:56, Viresh Kumar wrote: > Hi Thomas, > > On 28 February 2014 18:52, Thomas Gleixner wrote: >> On Fri, 28 Feb 2014, Viresh Kumar wrote: >> >>> Currently we are using two lowest bit of base for internal purpose and so they >>> both should be zero in the allocated address. The code was doing the right thing >>> before this patch came in: >>> >>> commit c5f66e99b7cb091e3d51ae8e8156892e8feb7fa3 >>> Author: Tejun Heo >>> Date: Wed Aug 8 11:10:28 2012 -0700 >>> >>> timer: Implement TIMER_IRQSAFE >>> >>> Tejun probably forgot to update this piece of code which checks if the lowest >>> 'n' bits are zero or not and so wasn't updated according to the new flag. Lets >>> use TIMER_FLAG_MASK in the calculations here, so that this code wouldn't require >>> a change later on with another flag in. >> >> Are you planning to introduce more flag horror? Don't go there. The >> timer_list code is about to be rewritten completely and I'm not going >> to add new features to the existing code base. > > Do you already have stuff prepared that can be shared on that? I am asking > because I am working on some CPU isolation stuff for Networking domain and > it looks like I need to add another of these flags :( .. I know its > just not acceptable > and so wanted your thoughts on how can I get things fixed. > > Peter asked me to implement something like cpuset.quiesce to move away all > timers/workqueues/etc from a cpuset. It was proposed here: > > https://lkml.org/lkml/2014/1/15/186 > > Now, I was looking to migrate away the timers first but I obviously > shouldn't migrate > the pinned timers. One way out to identify PINNED timers is to mark them PINNED > with the flag bits, which you wouldn't allow. Can you give some other idea with > which I can get this solved. Ping!!