Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758704Ab1DYR2M (ORCPT ); Mon, 25 Apr 2011 13:28:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:14955 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758551Ab1DYR2K (ORCPT ); Mon, 25 Apr 2011 13:28:10 -0400 Date: Mon, 25 Apr 2011 19:26:44 +0200 From: Oleg Nesterov To: Tejun Heo Cc: Linus Torvalds , Andrew Morton , "Nikita V. Youshchenko" , Matt Fleming , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] signal: sys_rt_sigtimedwait: simplify the timeout logic Message-ID: <20110425172644.GA20689@redhat.com> References: <20110418134421.GA15951@redhat.com> <20110418173224.GA27918@redhat.com> <20110423175901.GA484@redhat.com> <20110423175922.GB484@redhat.com> <20110425113746.GM17734@mtj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110425113746.GM17734@mtj.dyndns.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1073 Lines: 28 On 04/25, Tejun Heo wrote: > > On Sat, Apr 23, 2011 at 07:59:22PM +0200, Oleg Nesterov wrote: > > > > I don't understand why we are adding (ts.tv_sec || ts.tv_nsec) to > > timespec_to_jiffies(&ts). Perhaps to ensure we will sleep at least > > one jiffy if ts != 0? But in this case we should only check tv_nsec, > > I don't think timespec_to_jiffies() can return zero if tv_sec != 0. > > In fact I suspect timespec_to_jiffies() can only return zero if > > tv_sec == tv_nsec == 0 because we add "TICK_NSEC - 1", but I am not > > sure I understand correctly this math. > > > It might be a good idea to note the weird jiffies calculation with a > comment? If only I knew what this comment could say except /* Why do we add (tv_sec || tv_nsec) ? */ I'd better send 4/3 which simply removes this (I hope) unneeded code. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/