Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751377AbaLOMtY (ORCPT ); Mon, 15 Dec 2014 07:49:24 -0500 Received: from mail-ig0-f170.google.com ([209.85.213.170]:61824 "EHLO mail-ig0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750753AbaLOMtV (ORCPT ); Mon, 15 Dec 2014 07:49:21 -0500 MIME-Version: 1.0 In-Reply-To: <7561c096c7de603ac39fcfcff7bd2ec80589cae1.1418618044.git.osandov@osandov.com> References: <7561c096c7de603ac39fcfcff7bd2ec80589cae1.1418618044.git.osandov@osandov.com> Date: Mon, 15 Dec 2014 07:49:20 -0500 X-Google-Sender-Auth: 4XsMfnUD_WmZZXHKouRlmX7tOaI Message-ID: Subject: Re: [PATCH 1/8] nfs: follow direct I/O write locking convention From: Trond Myklebust To: Omar Sandoval Cc: Alexander Viro , Andrew Morton , Christoph Hellwig , David Sterba , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 15, 2014 at 12:26 AM, Omar Sandoval wrote: > The generic callers of direct_IO lock i_mutex before doing a write. NFS > doesn't use the generic write code, so it doesn't follow this > convention. This is now a problem because the interface introduced for > swap-over-NFS calls direct_IO for a write without holding i_mutex, but > other implementations of direct_IO will expect to have it locked. I really don't care much about swap-over-NFS performance; that's a niche usage at best. I _do_ care about O_DIRECT performance, and the ability to run multiple WRITE calls in parallel. IOW: Patch NACKed... Please find another solution. Trond -- 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/