Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 15 Mar 2003 05:25:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 15 Mar 2003 05:25:30 -0500 Received: from packet.digeo.com ([12.110.80.53]:28296 "EHLO packet.digeo.com") by vger.kernel.org with ESMTP id ; Sat, 15 Mar 2003 05:25:29 -0500 Date: Sat, 15 Mar 2003 02:36:14 -0800 From: Andrew Morton To: Alex Tomas Cc: linux-kernel@vger.kernel.org, ext2-devel@lists.sourceforge.net Subject: Re: [PATCH] remove BKL from ext2's readdir Message-Id: <20030315023614.3e28e67b.akpm@digeo.com> In-Reply-To: References: X-Mailer: Sylpheed version 0.8.9 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 15 Mar 2003 10:36:04.0913 (UTC) FILETIME=[AE629210:01C2EADE] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 949 Lines: 34 Alex Tomas wrote: > > > hi! > > I took a look at readdir() in 2.5.64's ext2 and found it serialized by BKL. Yes, I had this in -mm for ages, seem to have lost it. Also removal of BKL from lseek(). The theory is that the lock is there to avoid f_pos races against lseek. We ended up deciding that the way to address this is to ensure that all readdir implementations do: foo_readdir() { loff_t pos = file->f_pos; .... f_pos, but which modifies pos> ... file->f_pos = pos; } ext2 does this right and does not need the lock_kernel(). Once all filesystems have been audited (and, if necessary, fixed) we can remove the BKL from lseek also. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/