From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753205Ab0I2L5L (ORCPT ); Wed, 29 Sep 2010 07:57:11 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:7344 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752122Ab0I2L5J (ORCPT ); Wed, 29 Sep 2010 07:57:09 -0400 Message-ID: <4CA32982.1090809@parallels.com> Date: Wed, 29 Sep 2010 15:56:50 +0400 From: Pavel Emelyanov User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.11) Gecko/20100720 Fedora/3.0.6-1.fc12 Thunderbird/3.0.6 MIME-Version: 1.0 To: Jerome Marchand CC: Matthew Wilcox , Linux Kernel Mailing List Subject: Re: [PATCH] procfs: fix numbering in /proc/locks References: <4CA0B4A5.1090701@redhat.com> <4CA0B743.2050801@parallels.com> <4CA32626.8040700@redhat.com> <4CA32677.2020203@parallels.com> <4CA3288F.4030200@redhat.com> In-Reply-To: <4CA3288F.4030200@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/29/2010 03:52 PM, Jerome Marchand wrote: > On 09/29/2010 01:43 PM, Pavel Emelyanov wrote: >>> Good point. My implementation is definitely wrong. But I'm afraid that >>> moving the increment in locks_next() won't help either. It will fail when >>> a program do something more than just read the file sequentially (use >>> of lseek() for instance). We need a better way to keep track of the >>> current position in the list. >> >> The seq files core implementation knows about the lseek and >> calls the seq_ops callbacks properly. >> > > Yes, but if read a few lines and then lseek() back. I'm afraid it will call > a few more locks_next() function and thus increase the counter again. No. If you lseek back it calls the locks_start which should reset the counter, and then will call locks_next. Can you try out my proposal and check whether it really works as expected? Thanks, Pavel