From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72D1AC43331 for ; Fri, 27 Mar 2020 17:34:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2D22E21D7E for ; Fri, 27 Mar 2020 17:34:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="ebzslUKX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2D22E21D7E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C8BF56B000E; Fri, 27 Mar 2020 13:34:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C3BDC6B0037; Fri, 27 Mar 2020 13:34:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B04366B006C; Fri, 27 Mar 2020 13:34:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0026.hostedemail.com [216.40.44.26]) by kanga.kvack.org (Postfix) with ESMTP id 94D246B000E for ; Fri, 27 Mar 2020 13:34:30 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 89A582C14 for ; Fri, 27 Mar 2020 17:34:30 +0000 (UTC) X-FDA: 76641841500.14.bat11_446b340a1551f X-HE-Tag: bat11_446b340a1551f X-Filterd-Recvd-Size: 5109 Received: from hqnvemgate24.nvidia.com (hqnvemgate24.nvidia.com [216.228.121.143]) by imf28.hostedemail.com (Postfix) with ESMTP for ; Fri, 27 Mar 2020 17:34:29 +0000 (UTC) Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate24.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Fri, 27 Mar 2020 10:32:50 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Fri, 27 Mar 2020 10:34:23 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Fri, 27 Mar 2020 10:34:23 -0700 Received: from [10.2.174.211] (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 27 Mar 2020 17:34:22 +0000 From: Zi Yan To: "Kirill A. Shutemov" CC: , Andrea Arcangeli , , , "Kirill A. Shutemov" Subject: Re: [PATCH 3/7] khugepaged: Drain LRU add pagevec to get rid of extra pins Date: Fri, 27 Mar 2020 13:34:20 -0400 X-Mailer: MailMate (1.13.1r5680) Message-ID: In-Reply-To: <20200327170601.18563-4-kirill.shutemov@linux.intel.com> References: <20200327170601.18563-1-kirill.shutemov@linux.intel.com> <20200327170601.18563-4-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL105.nvidia.com (172.20.187.12) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: multipart/signed; boundary="=_MailMate_E59B323E-9281-4760-BAF4-CA84DE210BFD_="; micalg=pgp-sha512; protocol="application/pgp-signature" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1585330370; bh=1Kx7XFAxdNBJeQ7qXAogTDkyGlkntLnrYXkf/zEAh0A=; h=X-PGP-Universal:From:To:CC:Subject:Date:X-Mailer:Message-ID: In-Reply-To:References:MIME-Version:X-Originating-IP: X-ClientProxiedBy:Content-Type; b=ebzslUKXeeikdCK/q6yyaqLJUTvJHGnx/huzwE71+D46UVasN0UiglnTkNc9RMWF7 0IZzqlllFfd82qjM51OZDHSclcUH0nFSJ4euMIxFo8YPY1O28WenjLVwXpaE6t1L5i JJDzElt3FdRPgHLUUChazgLCr9Q5Ci8N7QPv/qT9tBans+GCdK4yEbB5YQtDziv1kX y39BMgS7zQMGpPWwFkjg0y3Pv8WMnXu7BELHKywHblUppzGzBauVw25iudM/LPyzvL rQlL012T+iRuUZhrc9ibYB93uZYCcrFjxRUAfs8byZZ9Ug0RjAxw1d/CJKMlHjk49f 3BsE70JBT+3kQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --=_MailMate_E59B323E-9281-4760-BAF4-CA84DE210BFD_= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On 27 Mar 2020, at 13:05, Kirill A. Shutemov wrote: > __collapse_huge_page_isolate() may fail due to extra pin in the LRU add= > pagevec. It's petty common for swapin case: we swap in pages just to > fail due to the extra pin. > > Signed-off-by: Kirill A. Shutemov > --- > mm/khugepaged.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 14d7afc90786..39e0994abeb8 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -585,11 +585,19 @@ static int __collapse_huge_page_isolate(struct vm= _area_struct *vma, > * The page must only be referenced by the scanned process > * and page swap cache. > */ > + if (page_count(page) !=3D 1 + PageSwapCache(page)) { > + /* > + * Drain pagevec and retry just in case we can get rid > + * of the extra pin, like in swapin case. > + */ > + lru_add_drain(); > + } > if (page_count(page) !=3D 1 + PageSwapCache(page)) { > unlock_page(page); > result =3D SCAN_PAGE_COUNT; > goto out; > } > + > if (pte_write(pteval)) { > writable =3D true; > } else { > -- = > 2.26.0 Looks good to me. Is the added empty line intentional? Reviewed-by: Zi Yan =E2=80=94 Best Regards, Yan Zi --=_MailMate_E59B323E-9281-4760-BAF4-CA84DE210BFD_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEEh7yFAW3gwjwQ4C9anbJR82th+ooFAl5+ORwPHHppeUBudmlk aWEuY29tAAoJEJ2yUfNrYfqK9MMP/1nsFKGD1peS8idFNCM1mo3r5sZA9Kf8jcYH MIQYUcwgprJn9PVaL9DI605sISqVsS8D6LrlVKfv14MerGlOYJ4360QvjUNJrgeb GhNjVjzpP0AB0BcDtAemFW/ECT3x2/rP4+sVfr2iceJmbj5cybqb0GwAbvOcC3Dg E2a73gBMuXV8nEyXsl5h/Za2PU31aX5z2A42/67dMJVFTXpPppQNzvXsXHjxEoBL AzX9Y8B3SE+OY7mnchWcDWRmtGL4jDOpChdIhZE6lfebmDFzk9+59nEo8+QPQwpP pjFKq04kkwgALNp4aoAJp6DFpGDhJoN+xHYAxUQWxmVCCEJqg4QSHOL/rpaIDZ8m 0z4KdWe36F+ligELPjh1C5lKcprk6y2HJCJ9ET3OeSEfd+j6Ngdblzv4CFI16fU8 A36VAiEHu3rEW0Z2MpGy4c5LGndKBiByo1pblaZha0gwNQ0QM6FYc4nHHj9Kvv/6 gAs1JEasDtEEKqw+gUYtp/yD9c9xgY3FJLXMszXhw9l0KV7X2TtKbasYF3VrANDM R1BN7sVngTJZghkU6uhFZQpbFzBEpQ+nMp9hZfQmpP4pJR5NNJBYcg3aWrFPsRu8 xYy6W84AystU6VYzcpI5Q0r36acVOOa6Mmlm/H/92i5PB8LDBYs033Nkr4cLNV2B I2iJHWwr =HkBS -----END PGP SIGNATURE----- --=_MailMate_E59B323E-9281-4760-BAF4-CA84DE210BFD_=--