Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755780Ab0KVATO (ORCPT ); Sun, 21 Nov 2010 19:19:14 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:32961 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755245Ab0KVATN (ORCPT ); Sun, 21 Nov 2010 19:19:13 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Mon, 22 Nov 2010 09:13:34 +0900 From: KAMEZAWA Hiroyuki To: Minchan Kim Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Bob Liu , fujita.tomonori@lab.ntt.co.jp, m.nazarewicz@samsung.com, pawel@osciak.com, andi.kleen@intel.com, felipe.contreras@gmail.com, "akpm@linux-foundation.org" , "kosaki.motohiro@jp.fujitsu.com" Subject: Re: [PATCH 3/4] alloc_contig_pages() allocate big chunk memory using migration Message-Id: <20101122091334.8ea11a43.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20101121152556.GC20947@barrios-desktop> References: <20101119171033.a8d9dc8f.kamezawa.hiroyu@jp.fujitsu.com> <20101119171528.32674ef4.kamezawa.hiroyu@jp.fujitsu.com> <20101121152556.GC20947@barrios-desktop> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2352 Lines: 67 On Mon, 22 Nov 2010 00:25:56 +0900 Minchan Kim wrote: > On Fri, Nov 19, 2010 at 05:15:28PM +0900, KAMEZAWA Hiroyuki wrote: > > From: KAMEZAWA Hiroyuki > > > > Add an function to allocate contiguous memory larger than MAX_ORDER. > > The main difference between usual page allocator is that this uses > > memory offline technique (Isolate pages and migrate remaining pages.). > > > > I think this is not 100% solution because we can't avoid fragmentation, > > but we have kernelcore= boot option and can create MOVABLE zone. That > > helps us to allow allocate a contiguous range on demand. > > > > The new function is > > > > alloc_contig_pages(base, end, nr_pages, alignment) > > > > This function will allocate contiguous pages of nr_pages from the range > > [base, end). If [base, end) is bigger than nr_pages, some pfn which > > meats alignment will be allocated. If alignment is smaller than MAX_ORDER, > > it will be raised to be MAX_ORDER. > > > > __alloc_contig_pages() has much more arguments. > > > > > > Some drivers allocates contig pages by bootmem or hiding some memory > > from the kernel at boot. But if contig pages are necessary only in some > > situation, kernelcore= boot option and using page migration is a choice. > > > > Changelog: 2010-11-19 > > - removed no_search > > - removed some drain_ functions because they are heavy. > > - check -ENOMEM case > > > > Changelog: 2010-10-26 > > - support gfp_t > > - support zonelist/nodemask > > - support [base, end) > > - support alignment > > > > Signed-off-by: KAMEZAWA Hiroyuki > Acked-by: Minchan Kim > > Trivial comment below. > > > +EXPORT_SYMBOL_GPL(alloc_contig_pages); > > + > > +struct page *alloc_contig_pages_host(unsigned long nr_pages, int align_order) > > +{ > > + return __alloc_contig_pages(0, max_pfn, nr_pages, align_order, -1, > > + GFP_KERNEL | __GFP_MOVABLE, NULL); > > +} > > We need include #include for using max_pfn. > will add that. Thanks, -Kame -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/