From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 9D4036B01F0 for ; Tue, 6 Apr 2010 20:06:07 -0400 (EDT) Date: Tue, 6 Apr 2010 17:05:32 -0700 From: Andrew Morton Subject: Re: [PATCH 04/14] Allow CONFIG_MIGRATION to be set without CONFIG_NUMA or memory hot-remove Message-Id: <20100406170532.56c71031.akpm@linux-foundation.org> In-Reply-To: <1270224168-14775-5-git-send-email-mel@csn.ul.ie> References: <1270224168-14775-1-git-send-email-mel@csn.ul.ie> <1270224168-14775-5-git-send-email-mel@csn.ul.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Andrea Arcangeli , Christoph Lameter , Adam Litke , Avi Kivity , David Rientjes , Minchan Kim , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Fri, 2 Apr 2010 17:02:38 +0100 Mel Gorman wrote: > CONFIG_MIGRATION currently depends on CONFIG_NUMA or on the architecture > being able to hot-remove memory. The main users of page migration such as > sys_move_pages(), sys_migrate_pages() and cpuset process migration are > only beneficial on NUMA so it makes sense. > > As memory compaction will operate within a zone and is useful on both NUMA > and non-NUMA systems, this patch allows CONFIG_MIGRATION to be set if the > user selects CONFIG_COMPACTION as an option. > > ... > > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -172,6 +172,16 @@ config SPLIT_PTLOCK_CPUS > default "4" > > # > +# support for memory compaction > +config COMPACTION > + bool "Allow for memory compaction" > + def_bool y > + select MIGRATION > + depends on EXPERIMENTAL && HUGETLBFS && MMU > + help > + Allows the compaction of memory for the allocation of huge pages. Seems strange to depend on hugetlbfs. Perhaps depending on HUGETLB_PAGE would be more logical. But hang on. I wanna use compaction to make my order-4 wireless skb allocations work better! Why do you hate me? -- 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