From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 25 May 2006 19:33:36 -0700 (PDT) From: Christoph Lameter Subject: Re: [PATCH 1/3] mm: tracking shared dirty pages In-Reply-To: <000001c6806c$19403760$ce2a2080@eecs.berkeley.edu> Message-ID: References: <20060525135534.20941.91650.sendpatchset@lappy> <20060525135555.20941.36612.sendpatchset@lappy> <000001c6806c$19403760$ce2a2080@eecs.berkeley.edu> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="-858709878-441145819-1148610816=:15494" Sender: owner-linux-mm@kvack.org Return-Path: To: Jeff Anderson-Lee Cc: 'Christoph Lameter' , 'Peter Zijlstra' , linux-mm@kvack.org, linux-kernel@vger.kernel.org, 'Hugh Dickins' , 'Andrew Morton' , 'David Howells' , 'Martin Bligh' , 'Nick Piggin' , 'Linus Torvalds' List-ID: ---858709878-441145819-1148610816=:15494 Content-Type: TEXT/PLAIN; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE On Thu, 25 May 2006, Jeff Anderson-Lee wrote: > Christoph Lameter wrote: >=20 > > I am a bit confused about the need for Davids patch. set_page_dirty() i= s=20 > > already a notification that a page is to be dirtied. Why do we need it= =20 > > twice? set_page_dirty could return an error code and the file system ca= n=20 > > use the set_page_dirty() hook to get its notification. What we would ne= ed=20 > > to do is to make sure that set_page_dirty can sleep. >=20 > set_page_dirty() is actually called fairly late in the game by > zap_pte_range() and follow_page().=A0 Thus, it is a notification that a p= age > HAS BEEN dirtied and needs a writeback. The tracking patch changes that behavior. set_page_dirty is called before= =20 the write to the page occurs and so its similar to the new method=20 introduced by David's patch. =20 ---858709878-441145819-1148610816=:15494-- -- 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