From: Jan Kara Subject: Re: [PATCH] jbd/jbd2: remove obsolete summarise_journal_usage. Date: Thu, 5 May 2011 19:25:04 +0200 Message-ID: <20110505172504.GQ5323@quack.suse.cz> References: <1304610859-480-1-git-send-email-tm@tao.ma> <20110505161454.GM5323@quack.suse.cz> <4DC2CDDA.2000406@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jan Kara , Tao Ma , linux-ext4@vger.kernel.org To: Niraj Kulkarni Return-path: Received: from cantor.suse.de ([195.135.220.2]:60066 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754958Ab1EERZG (ORCPT ); Thu, 5 May 2011 13:25:06 -0400 Content-Disposition: inline In-Reply-To: <4DC2CDDA.2000406@gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hello, On Thu 05-05-11 21:48:34, Niraj Kulkarni wrote: > I have a question, if only one instance of kjournald is active > at any time, and committing transaction is well separated from > others, what is need of taking j_list_lock while operating on > committing transaction's lists? Other processes (e.g. journal_unmap_buffer()) can occasionally manipulate with lists of the committing transaction. Honza -- Jan Kara SUSE Labs, CR