From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id B4B326B004D for ; Mon, 29 Jun 2009 21:03:01 -0400 (EDT) Date: Tue, 30 Jun 2009 09:03:02 +0800 From: Shaohua Li Subject: Re: + memory-hotplug-exclude-isolated-page-from-pco-page-alloc.patch added to -mm tree Message-ID: <20090630010302.GD21254@sli10-desk.sh.intel.com> References: <200906291949.n5TJnrsO028716@imap1.linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Christoph Lameter Cc: "akpm@linux-foundation.org" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "mel@csn.ul.ie" , "Zhao, Yakui" List-ID: On Tue, Jun 30, 2009 at 06:20:00AM +0800, Christoph Lameter wrote: > On Mon, 29 Jun 2009, akpm@linux-foundation.org wrote: > > > Pages marked as isolated should not be allocated again. If such pages > > reside in pcp list, they can be allocated too, so there is a ping-pong > > memory offline frees some pages to pcp list and the pages get allocated > > and then memory offline frees them again, this loop will happen again and > > again. > > Isolated pages are freed? Could they not be kept on a separate > list with refcount elevated until the isolation procedure is complete? Yes, they can be freed and add into pcp list. Moving them to a separate list is feasible, but the approach is more intrusive to me. As I explained in the patch, adding check in buffered_rmqueue() should hasn't impact for normal path. Thanks, Shaohua -- 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