From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id C191C6B01F4 for ; Tue, 17 Aug 2010 10:21:49 -0400 (EDT) Date: Tue, 17 Aug 2010 16:21:44 +0200 From: Andi Kleen Subject: Re: [RFC] [PATCH 2/4] dio: add page locking for direct I/O Message-ID: <20100817142144.GB18161@basil.fritz.box> References: <1281432464-14833-1-git-send-email-n-horiguchi@ah.jp.nec.com> <20100812075323.GA6112@spritzera.linux.bs1.fc.nec.co.jp> <20100812075941.GD6112@spritzera.linux.bs1.fc.nec.co.jp> <20100816020737.GA19531@spritzera.linux.bs1.fc.nec.co.jp> <20100817081753.GA28762@spritzera.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Jeff Moyer Cc: Naoya Horiguchi , Christoph Lameter , Andi Kleen , Andrew Morton , Mel Gorman , Wu Fengguang , Jun'ichi Nomura , linux-mm , LKML , Andrea Arcangeli List-ID: On Tue, Aug 17, 2010 at 09:46:56AM -0400, Jeff Moyer wrote: > Naoya Horiguchi writes: > > > BTW, from the discussion with Christoph I noticed my misunderstanding > > about the necessity of additional page locking. It would seem that > > without page locking there is no danger of racing between direct I/O and > > page migration. So I retract this additional locking patch-set. > > OK, great! ;-) Well it sounds like we still may need something. It isn't good if O_DIRECT can starve (or DoS) migration. -Andi -- ak@linux.intel.com -- Speaking for myself only. -- 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