From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757221Ab2DIOfb (ORCPT ); Mon, 9 Apr 2012 10:35:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:25997 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753106Ab2DIOfa (ORCPT ); Mon, 9 Apr 2012 10:35:30 -0400 From: Jeff Moyer To: Wu Fengguang Cc: Andrew Morton , Jens Axboe , linux-fsdevel@vger.kernel.org, LKML , Dave Chinner , Christoph Hellwig , Jan Kara , Chris Mason , Shaohua Li Subject: Re: [RESEND][PATCH v2] block: remove plugging at buffered write time References: <20120408010600.GA31377@localhost> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Mon, 09 Apr 2012 10:34:44 -0400 In-Reply-To: <20120408010600.GA31377@localhost> (Wu Fengguang's message of "Sun, 8 Apr 2012 09:06:00 +0800") Message-ID: User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wu Fengguang writes: > Buffered write(2) is not directly tied to IO, so it's not suitable to > handle plug in generic_file_aio_write(). [snip, moved] > Note that plugging for O_SYNC writes is also removed. The user may pass > arbitrary @size arguments, which may be much larger than the preferable > I/O size, or may cross extent/device boundaries. Let the lower layers > handle the plugging. Otherwise the plugging code here will turn the > low level plugging into no-ops. I assume you have some numbers to back this up, right? Care to share those? > Also moves unplugging for direct I/O from around ->direct_IO() down to > do_blockdev_direct_IO(). This could be handled in a separate patch. Acked-by: Jeff Moyer for this part. Cheers, Jeff