From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 9D9B46B004A for ; Fri, 19 Nov 2010 03:16:18 -0500 (EST) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id oAJ8GDem014390 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Fri, 19 Nov 2010 17:16:13 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id EA23445DE4F for ; Fri, 19 Nov 2010 17:16:12 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (s5.gw.fujitsu.co.jp [10.0.50.95]) by m5.gw.fujitsu.co.jp (Postfix) with ESMTP id BE09745DE4E for ; Fri, 19 Nov 2010 17:16:12 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id EEC9CE08003 for ; Fri, 19 Nov 2010 17:16:11 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 72B73E08007 for ; Fri, 19 Nov 2010 17:16:11 +0900 (JST) Date: Fri, 19 Nov 2010 17:10:33 +0900 From: KAMEZAWA Hiroyuki Subject: [PATCH 0/4] big chunk memory allocator v4 Message-Id: <20101119171033.a8d9dc8f.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: "linux-mm@kvack.org" Cc: "linux-kernel@vger.kernel.org" , minchan.kim@gmail.com, 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" List-ID: Hi, this is an updated version. No major changes from the last one except for page allocation function. removed RFC. Order of patches is [1/4] move some functions from memory_hotplug.c to page_isolation.c [2/4] search physically contiguous range suitable for big chunk alloc. [3/4] allocate big chunk memory based on memory hotplug(migration) technique [4/4] modify page allocation function. For what: I hear there is requirements to allocate a chunk of page which is larger than MAX_ORDER. Now, some (embeded) device use a big memory chunk. To use memory, they hide some memory range by boot option (mem=) and use hidden memory for its own purpose. But this seems a lack of feature in memory management. This patch adds alloc_contig_pages(start, end, nr_pages, gfp_mask) to allocate a chunk of page whose length is nr_pages from [start, end) phys address. This uses similar logic of memory-unplug, which tries to offline [start, end) pages. By this, drivers can allocate 30M or 128M or much bigger memory chunk on demand. (I allocated 1G chunk in my test). But yes, because of fragmentation, this cannot guarantee 100% alloc. If alloc_contig_pages() is called in system boot up or movable_zone is used, this allocation succeeds at high rate. I tested this on x86-64, and it seems to work as expected. But feedback from embeded guys are appreciated because I think they are main user of this function. Thanks, -Kame -- 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