From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757277AbaAIJXd (ORCPT ); Thu, 9 Jan 2014 04:23:33 -0500 Received: from mail-wg0-f45.google.com ([74.125.82.45]:61121 "EHLO mail-wg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753033AbaAIJWM (ORCPT ); Thu, 9 Jan 2014 04:22:12 -0500 From: Michal Nazarewicz To: Joonsoo Kim , Andrew Morton Cc: "Kirill A. Shutemov" , Rik van Riel , Jiang Liu , Mel Gorman , Cody P Schafer , Johannes Weiner , Michal Hocko , Minchan Kim , Andi Kleen , Wei Yongjun , Tang Chen , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim , Joonsoo Kim Subject: Re: [PATCH 7/7] mm/page_alloc: don't merge MIGRATE_(CMA|ISOLATE) pages on buddy In-Reply-To: <1389251087-10224-8-git-send-email-iamjoonsoo.kim@lge.com> Organization: http://mina86.com/ References: <1389251087-10224-1-git-send-email-iamjoonsoo.kim@lge.com> <1389251087-10224-8-git-send-email-iamjoonsoo.kim@lge.com> User-Agent: Notmuch/0.17+15~gb65ca8e (http://notmuchmail.org) Emacs/24.3.50.1 (x86_64-unknown-linux-gnu) X-Face: PbkBB1w#)bOqd`iCe"Ds{e+!C7`pkC9a|f)Qo^BMQvy\q5x3?vDQJeN(DS?|-^$uMti[3D*#^_Ts"pU$jBQLq~Ud6iNwAw_r_o_4]|JO?]}P_}Nc&"p#D(ZgUb4uCNPe7~a[DbPG0T~!&c.y$Ur,=N4RT>]dNpd;KFrfMCylc}gc??'U2j,!8%xdD Face: 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 X-PGP: 50751FF4 X-PGP-FP: AC1F 5F5C D418 88F8 CC84 5858 2060 4012 5075 1FF4 X-Hashcash: 1:20:140109:linux-kernel@vger.kernel.org::RphoQIjoM9LV07R7:00000000000000000000000000000000001uQ X-Hashcash: 1:20:140109:yongjun_wei@trendmicro.com.cn::tM99tOQzUZnsyqFE:000000000000000000000000000000000alT X-Hashcash: 1:20:140109:iamjoonsoo.kim@lge.com::ntUPk1ED9BEr0jR0:0000000000000000000000000000000000000000ZlG X-Hashcash: 1:20:140109:kirill.shutemov@linux.intel.com::7S4QXEFQuWmEKaQn:0000000000000000000000000000000uVt X-Hashcash: 1:20:140109:mgorman@suse.de::K6Mi2fkhcTS57C41:001AxB X-Hashcash: 1:20:140109:tangchen@cn.fujitsu.com::7Bmj3k0WMeftAk0y:000000000000000000000000000000000000000wTZ X-Hashcash: 1:20:140109:linux-mm@kvack.org::DXFig+S22B+Met13:00000000000000000000000000000000000000000001MV5 X-Hashcash: 1:20:140109:mhocko@suse.cz::AVmyIBA53MtRjjKZ:0001dJ5 X-Hashcash: 1:20:140109:hannes@cmpxchg.org::bRNNbzh9RX3asE7l:000000000000000000000000000000000000000000028yE X-Hashcash: 1:20:140109:riel@redhat.com::MZArinu+/RqB/MTE:002ePB X-Hashcash: 1:20:140109:cody@linux.vnet.ibm.com::jF52nVIYGz15UdYm:000000000000000000000000000000000000002PRT X-Hashcash: 1:20:140109:jiang.liu@huawei.com::ddw91mKCrgvO5Bt0:000000000000000000000000000000000000000003WHz X-Hashcash: 1:20:140109:iamjoonsoo.kim@lge.com::l1gKuEYbzO9FhfBe:0000000000000000000000000000000000000005wFY X-Hashcash: 1:20:140109:js1304@gmail.com::m9dJbwiwe0CI8+c/:092Ja X-Hashcash: 1:20:140109:ak@linux.intel.com::7HhRCNIBMW5v05Cq:00000000000000000000000000000000000000000009QGo X-Hashcash: 1:20:140109:akpm@linux-foundation.org::thunFytmzktdiFdK:000000000000000000000000000000000000BvWc X-Hashcash: 1:20:140109:minchan@kernel.org::IEJyJ+tatijw71Sm:0000000000000000000000000000000000000000000Ef+u Date: Thu, 09 Jan 2014 10:22:02 +0100 Message-ID: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="=-=-=" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Thu, Jan 09 2014, Joonsoo Kim wrote: > If (MAX_ORDER-1) is greater than pageblock order, there is a possibility > to merge different migratetype pages and to be linked in unintended > freelist. > > While I test CMA, CMA pages are merged and linked into MOVABLE freelist > by above issue and then, the pages change their migratetype to UNMOVABLE = by > try_to_steal_freepages(). After that, CMA to this region always fail. > > To prevent this, we should not merge the page on MIGRATE_(CMA|ISOLATE) > freelist. This is strange. CMA regions are always multiplies of max-pages (or pageblocks whichever is larger), so MOVABLE free pages should never be inside of a CMA region. If what you're describing happens, it looks like an issue somewhere else. > Signed-off-by: Joonsoo Kim > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 2548b42..ea99cee 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -581,6 +581,15 @@ static inline void __free_one_page(struct page *page, > __mod_zone_freepage_state(zone, 1 << order, > migratetype); > } else { > + int buddy_mt =3D get_buddy_migratetype(buddy); > + > + /* We don't want to merge cma, isolate pages */ > + if (unlikely(order >=3D pageblock_order) && > + migratetype !=3D buddy_mt && > + (migratetype >=3D MIGRATE_PCPTYPES || > + buddy_mt >=3D MIGRATE_PCPTYPES)) { > + break; > + } > list_del(&buddy->lru); > zone->free_area[order].nr_free--; > rmv_page_order(buddy); > --=20 > 1.7.9.5 > --=20 Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=3D./ `o ..o | Computer Science, Micha=C5=82 =E2=80=9Cmina86=E2=80=9D Nazarewicz = (o o) ooo +------ooO--(_)--Ooo-- --=-=-= Content-Type: multipart/signed; boundary="==-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" --==-=-= Content-Type: text/plain --==-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBAgAGBQJSzmo6AAoJECBgQBJQdR/0hXcP+gNcSKtRGUP6Z1/0L4u+rMIp oJqXjZ1M6kSzqPYeTEZhHqJLOMLYJfEmDAzUkP3xeVvnqv0HatHjcn5JDklkv9PT gOQ1sflANnIwIw930rVLQQM5s0QhR4gic+CnJ7Sc9YPadopn1l+JQHy/93ylXruU /+g23QCFS+uQoQZ6HqhJS2AXXworLMTi9IA/YA1PuMXLDpnlhLFh9tkeJeWIR+rX Frr7U35NeZtWyKbHSZttULJGFAtscD0mdHP79Bnqzosyqi92HyjSoIjzOCe4ptkM FMie0i9Rx/NiRVRNOzQrsI7ryr1RR/lXhbcmTYyvMfxBuzbXW3/r1gQEIuJvDpJ/ Us9zl2ayWpFvjgBE9m/4vawZO/+PGVsv74iVcL60KgEuftAPyYHqkYeAf8cI8WOh CgKpR6oyUOFp81kX0GeEJ2b5JJh+lOzmufg4Ow1eLgQWpBY/u02hQ/sLyEpHgqiu ZfgYBNP5horayy6VqIrnw1/oIBg2CUp31RQtJ5sB+AaGHTtd7cw1X8PblLWRJvsn ErdJKRJV1fe/bnwD3EEt5iI8Y9oCOB6mTI5pHWhdIunBEG0//J8qYpqk+U9jfB6Q BsLwO55NOyC5MzRmaXLcLGmmn+ENfPDrcugtmwqOK1SNKK2NOKN6Q0cGuu0Sa+8Z 2fcUX72K8i+6h1sDR1vt =vPh+ -----END PGP SIGNATURE----- --==-=-=-- --=-=-=--