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=-8.4 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, USER_AGENT_SANE_1 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 7EB72C3F2D8 for ; Thu, 5 Mar 2020 22:30:04 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 423EE206E6 for ; Thu, 5 Mar 2020 22:30:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="RSHxAgBT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 423EE206E6 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 ACD9B6B0005; Thu, 5 Mar 2020 17:30:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A7DAA6B0006; Thu, 5 Mar 2020 17:30:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 945226B0007; Thu, 5 Mar 2020 17:30:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0160.hostedemail.com [216.40.44.160]) by kanga.kvack.org (Postfix) with ESMTP id 7A7A66B0005 for ; Thu, 5 Mar 2020 17:30:03 -0500 (EST) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 38197181AC9B6 for ; Thu, 5 Mar 2020 22:30:03 +0000 (UTC) X-FDA: 76562752686.29.sense28_3a954b3de8c4f X-HE-Tag: sense28_3a954b3de8c4f X-Filterd-Recvd-Size: 5465 Received: from hqnvemgate24.nvidia.com (hqnvemgate24.nvidia.com [216.228.121.143]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Thu, 5 Mar 2020 22:30:02 +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 ; Thu, 05 Mar 2020 14:28:35 -0800 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Thu, 05 Mar 2020 14:30:00 -0800 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Thu, 05 Mar 2020 14:30:00 -0800 Received: from [10.110.48.28] (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 5 Mar 2020 22:30:00 +0000 Subject: Re: [PATCH v3 1/2] mm/gup: fixup for 9947ea2c1e608e32 "mm/gup: track FOLL_PIN pages" To: Claudio Imbrenda , , , , CC: , , , , , , , References: <20200304130655.462517-1-imbrenda@linux.ibm.com> <20200304130655.462517-2-imbrenda@linux.ibm.com> From: John Hubbard X-Nvconfidentiality: public Message-ID: <09e0d5ec-c799-be0b-b85e-39c1c5d2c3cd@nvidia.com> Date: Thu, 5 Mar 2020 14:29:59 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200304130655.462517-2-imbrenda@linux.ibm.com> X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL111.nvidia.com (172.20.187.18) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1583447315; bh=G0GpTxxXqdbtdW7cvxOSO9IvDVSA9OIAX1/SJBkdy8s=; h=X-PGP-Universal:Subject:To:CC:References:From:X-Nvconfidentiality: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=RSHxAgBTLKqlsZQt0fTf/84P0PyKMR6VEDO7qYpR5iLwVoHGHmSOrhs3OZP1atZ25 lMA2bwFQiucKM67o/Rz2ZB/KPh26k7wlfcEaFGyhqpsph8Cnq2PMqiiJprHKlfkZYU DpNRPLh6+a3VpKTd8ZEeUNmZcC/DC1/OWB+8T+dRtWftUOJ7NkQFEgJ8rfL25QTQq6 qp0jpqcukDDh+9aNcOrQEE5Lhn5aKcLYyRIUS0jyuBJu4Scn98swF+zLKEIpESexuJ GdUWFCloHvAKcsZ63yopSJbeZNM2N+t4Psmg2H6Wt6a/+E6oePSZ8nHrQDG0Arv82i q6qgwq1M/unkA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 3/4/20 5:06 AM, Claudio Imbrenda wrote: > In case pin fails, we need to unpin, a simple put_page will not be enough > > fixup for commit 9947ea2c1e608e32 ("mm/gup: track FOLL_PIN pages") > > it can be simply squashed in > > Signed-off-by: Claudio Imbrenda > --- Although it won't show up anywhere, in case this helps Andrew sort out what has been looked at, you can add: Reviewed-by: John Hubbard thanks, -- John Hubbard NVIDIA > mm/gup.c | 46 +++++++++++++++++++++++----------------------- > 1 file changed, 23 insertions(+), 23 deletions(-) > > diff --git a/mm/gup.c b/mm/gup.c > index f589299b0d4a..81a95fbe9901 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -116,6 +116,28 @@ static __maybe_unused struct page *try_grab_compound_head(struct page *page, > return NULL; > } > > +static void put_compound_head(struct page *page, int refs, unsigned int flags) > +{ > + if (flags & FOLL_PIN) { > + mod_node_page_state(page_pgdat(page), NR_FOLL_PIN_RELEASED, > + refs); > + > + if (hpage_pincount_available(page)) > + hpage_pincount_sub(page, refs); > + else > + refs *= GUP_PIN_COUNTING_BIAS; > + } > + > + VM_BUG_ON_PAGE(page_ref_count(page) < refs, page); > + /* > + * Calling put_page() for each ref is unnecessarily slow. Only the last > + * ref needs a put_page(). > + */ > + if (refs > 1) > + page_ref_sub(page, refs - 1); > + put_page(page); > +} > + > /** > * try_grab_page() - elevate a page's refcount by a flag-dependent amount > * > @@ -2134,7 +2156,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, > goto pte_unmap; > > if (unlikely(pte_val(pte) != pte_val(*ptep))) { > - put_page(head); > + put_compound_head(head, 1, flags); > goto pte_unmap; > } > > @@ -2267,28 +2289,6 @@ static int record_subpages(struct page *page, unsigned long addr, > return nr; > } > > -static void put_compound_head(struct page *page, int refs, unsigned int flags) > -{ > - if (flags & FOLL_PIN) { > - mod_node_page_state(page_pgdat(page), NR_FOLL_PIN_RELEASED, > - refs); > - > - if (hpage_pincount_available(page)) > - hpage_pincount_sub(page, refs); > - else > - refs *= GUP_PIN_COUNTING_BIAS; > - } > - > - VM_BUG_ON_PAGE(page_ref_count(page) < refs, page); > - /* > - * Calling put_page() for each ref is unnecessarily slow. Only the last > - * ref needs a put_page(). > - */ > - if (refs > 1) > - page_ref_sub(page, refs - 1); > - put_page(page); > -} > - > #ifdef CONFIG_ARCH_HAS_HUGEPD > static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end, > unsigned long sz) >