Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262291AbVBVNAh (ORCPT ); Tue, 22 Feb 2005 08:00:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262290AbVBVNAh (ORCPT ); Tue, 22 Feb 2005 08:00:37 -0500 Received: from smtp2.rz.tu-harburg.de ([134.28.205.13]:57200 "EHLO smtp2.rz.tu-harburg.de") by vger.kernel.org with ESMTP id S262288AbVBVNAa (ORCPT ); Tue, 22 Feb 2005 08:00:30 -0500 Message-ID: <1109077222.421b2ce6739f8@webmail.tu-harburg.de> Date: Tue, 22 Feb 2005 14:00:22 +0100 From: Jan Blunck To: Alex Tomas Cc: Alexander Viro , Linux-Kernel Mailing List , linux-fsdevel Subject: Re: [RFC] pdirops: vfs patch References: <1109073273.421b1d7923204@webmail.tu-harburg.de> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT User-Agent: Internet Messaging Program (IMP) 3.2.5 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 918 Lines: 29 Quoting Alex Tomas : > >>>>> Jan Blunck (JB) writes: > > >> 1) i_sem protects dcache too > > JB> Where? i_sem is the per-inode lock, and shouldn't be used else. > > read comments in fs/namei.c:read_lookup() > i_sem does NOT protect the dcache. Also not in real_lookup(). The lock must be acquired for ->lookup() and because we might sleep on i_sem, we have to get it early and check for repopulation of the dcache. > we've already done this for ext3. it works. > it speeds some loads up significantly. > especially on big directories. > and you can control this via mount option, > so almost zero cost for fs that doesn't support pdirops. Ok. Jan - 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/