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 SMTP id B07B56B0089 for ; Thu, 18 Nov 2010 05:43:16 -0500 (EST) Subject: Re: [PATCH 3/3] mlock: avoid dirtying pages and triggering writeback Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: Theodore Tso In-Reply-To: <20101118054629.GA3339@amd> Date: Thu, 18 Nov 2010 05:43:06 -0500 Content-Transfer-Encoding: quoted-printable Message-Id: <2ADBEB7E-0EC8-4536-B556-0453A8E1D5FA@mit.edu> References: <1289996638-21439-1-git-send-email-walken@google.com> <1289996638-21439-4-git-send-email-walken@google.com> <20101117125756.GA5576@amd> <1290007734.2109.941.camel@laptop> <20101118054629.GA3339@amd> Sender: owner-linux-mm@kvack.org To: Nick Piggin Cc: Peter Zijlstra , Michel Lespinasse , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Hugh Dickins , Rik van Riel , Kosaki Motohiro , Theodore Tso , Michael Rubin , Suleiman Souhlal List-ID: On Nov 18, 2010, at 12:46 AM, Nick Piggin wrote: > The right way to fix this would not be to introduce the new regression > but either/both: a specific syscall to mlock-for-read which does not = do > any reservations, fix filesystem hook to allow reservation without > implying dirtying. A simple flag to page_mkwrite will be enough (plus > the logic to call it from VM). Why is it at all important that mlock() force block allocation for = sparse blocks? It's not at all specified in the mlock() API = definition that it does that. Are there really programs that assume that mlock() =3D=3D fallocate()?!? -- Ted -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org