From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932540AbWFST2y (ORCPT ); Mon, 19 Jun 2006 15:28:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932543AbWFST2y (ORCPT ); Mon, 19 Jun 2006 15:28:54 -0400 Received: from mail.tv-sign.ru ([213.234.233.51]:35514 "EHLO several.ru") by vger.kernel.org with ESMTP id S932540AbWFST2y (ORCPT ); Mon, 19 Jun 2006 15:28:54 -0400 Date: Tue, 20 Jun 2006 03:28:56 +0400 From: Oleg Nesterov To: Roland McGrath Cc: Linus Torvalds , Andrew Morton , john stultz , Thomas Gleixner , Ingo Molnar , Steven Rostedt , Chris Wright , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] arm_timer: remove a racy and obsolete PF_EXITING check Message-ID: <20060619232856.GA88@oleg> References: <20060615161202.GA21463@oleg> <20060619080656.42097180049@magilla.sf.frob.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060619080656.42097180049@magilla.sf.frob.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 06/19, Roland McGrath wrote: > > > However, for some reason it does so only for CPUCLOCK_PERTHREAD > > case (which is imho wrong). > > For a process CPU clock timer, ->it.cpu.task is the thread group leader. > The group leader can exit and will be a lingering zombie for as long as > other threads in the group live. The process timers need to keep getting > armed and working both during and after the group leader's exit processing. Ah, yes. Also, I missed the fact that process_timer_rebalance() checks PF_EXITING anyway (For a process CPU clock timer), so I was wrong twice. Thanks! Oleg.