From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755665Ab1KOC7X (ORCPT ); Mon, 14 Nov 2011 21:59:23 -0500 Received: from mga02.intel.com ([134.134.136.20]:11005 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755378Ab1KOC7W (ORCPT ); Mon, 14 Nov 2011 21:59:22 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,351,1309762800"; d="scan'208";a="75399237" Message-ID: <1321325960.13860.75.camel@yhuang-dev> Subject: Re: Printk mulitple line message support From: Huang Ying To: Joe Perches Cc: William Douglas , Andrew Morton , "linux-kernel@vger.kernel.org" Date: Tue, 15 Nov 2011 10:59:20 +0800 In-Reply-To: <1321324217.8944.25.camel@Joe-Laptop> References: <1321253936.13860.35.camel@yhuang-dev> <1321281640.2004.6.camel@Joe-Laptop> <1321318201.13860.51.camel@yhuang-dev> <1321319883.8944.7.camel@Joe-Laptop> <1321321957.13860.64.camel@yhuang-dev> <1321324217.8944.25.camel@Joe-Laptop> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.0.3-2 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-11-15 at 10:30 +0800, Joe Perches wrote: > On Tue, 2011-11-15 at 09:52 +0800, Huang Ying wrote: > > On Tue, 2011-11-15 at 09:18 +0800, Joe Perches wrote: > > > I believe you are not solving any real problem > > > with pr__ml. > > > Most all interleaved complete line uses have some > > > pr_fmt prefix that distinguishes between the sources. > > Except dev_ and netdev_, it appears that many general > > pr_ do not have the prefix. > > I'm working on that. > There are a lot of them and it's a slog. Em... so you think we do not need a general solution? Just use various prefix for these pr_? The down side of this solution is that it is hard to use a simple script to distinguish interleaved message easily. > > > A perhaps larger problem is interleaved partial > > > lines with pr_cont. > > In an interleaved situation, how to determine for pr_cont? > > pr_cont has its own KERN_CONT level, it's "", which > is stripped from output by printk. It's used to continue > the previous printks output on a single line. Sorry. Had some misunderstanding about pr_cont. > > > I believe that an initiator/terminator is necessary > > > for reassembly. Something that could be used > > > with pr_, dev_, netdev_, et al. > > > > > > mp_start(&cookie) > > > pr_(fmt, ...); > > > > Do not need cookie here? > > Ideally not. > > > > pr_mp_cont(&cookie, fmt, ...); > > > pr_mp_cont(&cookie, fmt "\n", ...); > > > mp_end(&cookie); > > > > With initiator/terminator the kernel log will be more structural, but > > that will make kernel log a little harder to read too. > > Initiator/terminator would not be part of printk output > but could exist simply to set/track the atomic/cookie # > and have printk output the appropriate cookie id when > more than 1 cookie is active. Oh. I see. For multiple part in one line. I think the better solution may be to assemble them in a line buffer before real output to console to avoid interleaving. Do you think so? Best Regards, Huang Ying