From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f54.google.com (mail-oi0-f54.google.com [209.85.218.54]) by kanga.kvack.org (Postfix) with ESMTP id DC40C6B006E for ; Thu, 25 Jun 2015 05:54:27 -0400 (EDT) Received: by oigx81 with SMTP id x81so48733554oig.1 for ; Thu, 25 Jun 2015 02:54:27 -0700 (PDT) Received: from szxga03-in.huawei.com (szxga03-in.huawei.com. [119.145.14.66]) by mx.google.com with ESMTPS id 136si2142410oia.75.2015.06.25.02.54.25 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Thu, 25 Jun 2015 02:54:27 -0700 (PDT) Message-ID: <558BCD95.2090201@huawei.com> Date: Thu, 25 Jun 2015 17:44:53 +0800 From: Xishi Qiu MIME-Version: 1.0 Subject: Re: [RFC PATCH 10/12] mm: add the buddy system interface References: <55704A7E.5030507@huawei.com> <55704CC4.8040707@huawei.com> <557691E0.5020203@jp.fujitsu.com> <5576BA2B.6060907@huawei.com> <5577A9A9.7010108@jp.fujitsu.com> In-Reply-To: <5577A9A9.7010108@jp.fujitsu.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Kamezawa Hiroyuki Cc: Andrew Morton , nao.horiguchi@gmail.com, Yinghai Lu , "H. Peter Anvin" , Thomas Gleixner , mingo@elte.hu, Xiexiuqi , Hanjun Guo , "Luck, Tony" , Linux MM , LKML On 2015/6/10 11:06, Kamezawa Hiroyuki wrote: > On 2015/06/09 19:04, Xishi Qiu wrote: >> On 2015/6/9 15:12, Kamezawa Hiroyuki wrote: >> >>> On 2015/06/04 22:04, Xishi Qiu wrote: >>>> Add the buddy system interface for address range mirroring feature. >>>> Allocate mirrored pages in MIGRATE_MIRROR list. If there is no mirrored pages >>>> left, use other types pages. >>>> >>>> Signed-off-by: Xishi Qiu >>>> --- >>>> mm/page_alloc.c | 40 +++++++++++++++++++++++++++++++++++++++- >>>> 1 file changed, 39 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >>>> index d4d2066..0fb55288 100644 >>>> --- a/mm/page_alloc.c >>>> +++ b/mm/page_alloc.c >>>> @@ -599,6 +599,26 @@ static inline bool is_mirror_pfn(unsigned long pfn) >>>> >>>> return false; >>>> } >>>> + >>>> +static inline bool change_to_mirror(gfp_t gfp_flags, int high_zoneidx) >>>> +{ >>>> + /* >>>> + * Do not alloc mirrored memory below 4G, because 0-4G is >>>> + * all mirrored by default, and the list is always empty. >>>> + */ >>>> + if (high_zoneidx < ZONE_NORMAL) >>>> + return false; >>>> + >>>> + /* Alloc mirrored memory for only kernel */ >>>> + if (gfp_flags & __GFP_MIRROR) >>>> + return true; >>> >>> GFP_KERNEL itself should imply mirror, I think. >>> >> >> Hi Kame, >> >> How about like this: #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_MIRROR) ? >> > > Hm.... it cannot cover GFP_ATOMIC at el. > > I guess, mirrored memory should be allocated if !__GFP_HIGHMEM or !__GFP_MOVABLE Hi Kame, Can we distinguish allocations form user or kernel only by GFP flags? Thanks, Xishi Qiu -- 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