From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753569AbbFHTJJ (ORCPT ); Mon, 8 Jun 2015 15:09:09 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:49547 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752966AbbFHTJC convert rfc822-to-8bit (ORCPT ); Mon, 8 Jun 2015 15:09:02 -0400 Message-ID: <1433790523.1495.48.camel@twins> Subject: Re: [PATCH 0/3] hrtimer: HRTIMER_STATE_ fixes From: Peter Zijlstra To: Thomas Gleixner Cc: Oleg Nesterov , umgwanakikbuti@gmail.com, mingo@elte.hu, ktkhai@parallels.com, rostedt@goodmis.org, juri.lelli@gmail.com, pang.xunlei@linaro.org, wanpeng.li@linux.intel.com, linux-kernel@vger.kernel.org Date: Mon, 08 Jun 2015 21:08:43 +0200 In-Reply-To: References: <20150605084836.364306429@infradead.org> <20150605085205.723058588@infradead.org> <20150607223317.GA5193@redhat.com> <20150608091417.GM19282@twins.programming.kicks-ass.net> <20150608141709.GX18673@twins.programming.kicks-ass.net> <20150608151039.GA23138@redhat.com> <1433777745.1495.41.camel@twins> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2015-06-08 at 19:11 +0200, Thomas Gleixner wrote: > > Ah, yes, we could introduce timerqueue_is_queued() which uses > > RB_EMPTY_NODE(). Obviating the need for hrtimer::state entirely. > > Which won't work for the migration case unless we have some trickery > like we do with double linked lists (not setting the prev member to > NULL on dequeue). Yeah, that dawned on me while away from the computer.