From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263588AbUDBKpL (ORCPT ); Fri, 2 Apr 2004 05:45:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263589AbUDBKpL (ORCPT ); Fri, 2 Apr 2004 05:45:11 -0500 Received: from shuttle.eclipse.ncsc.mil ([144.51.102.80]:142 "EHLO eclipse.ncsc.mil") by vger.kernel.org with ESMTP id S263588AbUDBKpH (ORCPT ); Fri, 2 Apr 2004 05:45:07 -0500 From: "Robert W. Maloy" Reply-To: r.w.maloy@acm.org Organization: I331 (C41) To: Andrew Morton Subject: Re: Possible error in fs/buffer.c Date: Fri, 2 Apr 2004 05:46:57 -0500 User-Agent: KMail/1.5 Cc: linux-kernel@vger.kernel.org References: <200404011043.49077.r.w.maloy@acm.org> <20040401162627.7b3f48c7.akpm@osdl.org> In-Reply-To: <20040401162627.7b3f48c7.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200404020546.57471.r.w.maloy@acm.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Andrew Morton wrote: > This is saying "is the buffer is not on any list, then place it on > the mapping's list now. If the buffer _is_ already on some list > then we know it must already be on mapping->private_list, so we > have nothing to do". > > Re-dirtying an already-dirty buffer is an extremely common case, > and here we look for an opportunity to avoid dirtying a cacheline > or two. This makes some since except that buffer_insert_list(&buffer_mapping->private_lock, bh, &mapping->private_list); only adds &bh->b_assoc_buffers to the end of mapping->private_list not the buffer itself. -- Cheers Rob Maloy r.w.maloy@acm.org (410) 854-6637