From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758293Ab2I1Ot4 (ORCPT ); Fri, 28 Sep 2012 10:49:56 -0400 Received: from mail.eecsit.tu-berlin.de ([130.149.17.13]:65122 "EHLO mail.cs.tu-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757960Ab2I1Otz (ORCPT ); Fri, 28 Sep 2012 10:49:55 -0400 Message-ID: <5065B909.1060907@cs.tu-berlin.de> Date: Fri, 28 Sep 2012 16:49:45 +0200 From: =?UTF-8?B?IkphbiBILiBTY2jDtm5oZXJyIg==?= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.7) Gecko/20120919 Thunderbird/10.0.7 MIME-Version: 1.0 To: Kay Sievers CC: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Subject: Re: [PATCH] printk: drop ambiguous LOG_CONT flag References: <5064790E.4000207@cs.tu-berlin.de> <1348820728-13796-1-git-send-email-schnhrr@cs.tu-berlin.de> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 28.09.2012 16:34, schrieb Kay Sievers: > On Fri, Sep 28, 2012 at 10:25 AM, Jan H. Schönherr > That fails the racing task test, and a cont user that was nicely > merged before is now all in separate records. I guess, I need to extend my test cases. Do you have something ready that I could use? > It seems, unconditionally using the cont buffer like in your patch, > for all incoming messages just makes the entire cont merge buffer > dance useless when it comes to races. I see. :( > The current behaviour has the advantage, that non-cont users will not > race against a cont user (which is like 99.x% of the races I expect). > The cont buffer is currently only used when we expect a cont user, > non-cont users happening in the middle of a cont-print will not flush > the and disturb the cont buffer. That should be fixable by using a second set of flags, owner, and so on within vprintk... I still think, that getting rid of of remotely tracking the flags is worth something. (Ideally, we should also be able to correctly reassemble multiple simultaneous cont users. But that it still a bit out of scope I think.) Given that I'm able to fix the racing case, would you be in favor of this approach, or should we stick to the earlier version? Regards Jan