From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-f179.google.com (mail-ie0-f179.google.com [209.85.223.179]) by kanga.kvack.org (Postfix) with ESMTP id 491B46B0038 for ; Mon, 15 Dec 2014 07:49:22 -0500 (EST) Received: by mail-ie0-f179.google.com with SMTP id rp18so10686020iec.10 for ; Mon, 15 Dec 2014 04:49:22 -0800 (PST) Received: from mail-ie0-x236.google.com (mail-ie0-x236.google.com. [2607:f8b0:4001:c03::236]) by mx.google.com with ESMTPS id a3si6545598igg.49.2014.12.15.04.49.20 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 15 Dec 2014 04:49:21 -0800 (PST) Received: by mail-ie0-f182.google.com with SMTP id x19so10618131ier.27 for ; Mon, 15 Dec 2014 04:49:20 -0800 (PST) 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 Message-ID: Subject: Re: [PATCH 1/8] nfs: follow direct I/O write locking convention From: Trond Myklebust Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: 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 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org