From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753485AbaIPVdb (ORCPT ); Tue, 16 Sep 2014 17:33:31 -0400 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.228]:17533 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752512AbaIPVda (ORCPT ); Tue, 16 Sep 2014 17:33:30 -0400 Date: Tue, 16 Sep 2014 17:33:28 -0400 From: Steven Rostedt To: Jan Kara Cc: Markus Trippelsdorf , Geert Uytterhoeven , "linux-kernel@vger.kernel.org" , Andrew Morton , Peter Zijlstra Subject: Re: [PATCH] printk: git rid of [sched_delayed] message for printk_deferred Message-ID: <20140916173328.6306a5c2@gandalf.local.home> In-Reply-To: <20140916212250.GI1205@quack.suse.cz> References: <20140914050905.GA296@x4> <20140914055450.GB296@x4> <20140915163740.GA12408@x4> <20140916105547.GA1205@quack.suse.cz> <20140916144252.GB32118@x4> <20140916111331.14303381@gandalf.local.home> <20140916203510.GF1205@quack.suse.cz> <20140916170709.73ef2993@gandalf.local.home> <20140916212250.GI1205@quack.suse.cz> X-Mailer: Claws Mail 3.10.1 (GTK+ 2.24.24; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-RR-Connecting-IP: 107.14.168.142:25 X-Cloudmark-Score: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 16 Sep 2014 23:22:50 +0200 Jan Kara wrote: > > For the most part it's a blocking write. Yeah, if another CPU is > > writing, it wont be a blocking write, but it usually is, I know I > > depend on it (when I'm debugging, I usually don't have contention > > between CPUs). The important part is that they are done in order. A > > delayed print, wont be in order with other printks. That is still a > > crucial difference. > printk_deffered() will be in order with other printks after your commit > 458df9fd4815b47809875d57f42e16401674b621. Just printing to console itself > will be delayed to the next timer interrupt. Or am I missing something? Hehe, you're right. I blame the meds for forgetting this. Yeah, my update will put the data in order. Thus I guess I agree with your assessment. We probably don't need the "sched_delayed" anymore. OK, you convinced me, but I still like to hear Peter's view on this before we commit it. For Markus's patch: Acked-by: Steven Rostedt -- Steve