From patchwork Tue Mar 8 14:14:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12773878 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF870C433EF for ; Tue, 8 Mar 2022 14:18:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 790308D0014; Tue, 8 Mar 2022 09:18:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7183D8D0001; Tue, 8 Mar 2022 09:18:19 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 591D28D0014; Tue, 8 Mar 2022 09:18:19 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0161.hostedemail.com [216.40.44.161]) by kanga.kvack.org (Postfix) with ESMTP id 4A9FA8D0001 for ; Tue, 8 Mar 2022 09:18:19 -0500 (EST) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0F1751828B5DD for ; Tue, 8 Mar 2022 14:18:19 +0000 (UTC) X-FDA: 79221423918.17.F94FE0D Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf17.hostedemail.com (Postfix) with ESMTP id 93E0F4000E for ; Tue, 8 Mar 2022 14:18:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646749098; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=E2n5YxPaBAt4DbQTg1N/HEvM7OHIbsuhh5l7jJDC7c0=; b=c/Qjm2GvywfYKMgbXq0Vja2yX3wEac1WSwZhbPEwtVQNtPmGvg2+NH3a8vT97jHzwN1tBY siTVzgE1w5q3vtvo7VcRhiYFLC7FgYNRU14x4v0ZGGhSUYePUyDWtIlDXVRb3D20INm2y9 QE7gwoVPc6akMRBcZ5iZMJ9XV0zFGXE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-408-unSRJ_ClNwqMzqeAOFxPAw-1; Tue, 08 Mar 2022 09:18:15 -0500 X-MC-Unique: unSRJ_ClNwqMzqeAOFxPAw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DA0961800D50; Tue, 8 Mar 2022 14:18:11 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.195.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4E8A77886E; Tue, 8 Mar 2022 14:18:05 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: Andrew Morton , Hugh Dickins , Linus Torvalds , David Rientjes , Shakeel Butt , John Hubbard , Jason Gunthorpe , Mike Kravetz , Mike Rapoport , Yang Shi , "Kirill A . Shutemov" , Matthew Wilcox , Vlastimil Babka , Jann Horn , Michal Hocko , Nadav Amit , Rik van Riel , Roman Gushchin , Andrea Arcangeli , Peter Xu , Donald Dutile , Christoph Hellwig , Oleg Nesterov , Jan Kara , Liang Zhang , Pedro Gomes , Oded Gabbay , linux-mm@kvack.org, David Hildenbrand Subject: [PATCH v1 09/15] mm/rmap: use page_move_anon_rmap() when reusing a mapped PageAnon() page exclusively Date: Tue, 8 Mar 2022 15:14:31 +0100 Message-Id: <20220308141437.144919-10-david@redhat.com> In-Reply-To: <20220308141437.144919-1-david@redhat.com> References: <20220308141437.144919-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Rspamd-Queue-Id: 93E0F4000E X-Stat-Signature: p4cx67dz9qu5mmduex3z4h5sjdy4xa7o X-Rspam-User: Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="c/Qjm2Gv"; spf=none (imf17.hostedemail.com: domain of david@redhat.com has no SPF policy when checking 170.10.133.124) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Rspamd-Server: rspam07 X-HE-Tag: 1646749098-101370 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: We want to mark anonymous pages exclusive, and when using page_move_anon_rmap() we know that we are the exclusive user, as properly documented. This is a preparation for marking anonymous pages exclusive in page_move_anon_rmap(). In both instances, we're holding page lock and are sure that we're the exclusive owner (page_count() == 1). hugetlb already properly uses page_move_anon_rmap() in the write fault handler. Note that in case of a PTE-mapped THP, we'll only end up calling this function if the whole THP is only referenced by the single PTE mapping a single subpage (page_count() == 1); consequently, it's fine to modify the compound page mapping inside page_move_anon_rmap(). Signed-off-by: David Hildenbrand --- mm/huge_memory.c | 2 ++ mm/memory.c | 1 + 2 files changed, 3 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index c1f7eaba23ff..0b6fb409b9e4 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1317,6 +1317,8 @@ vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf) try_to_free_swap(page); if (page_count(page) == 1) { pmd_t entry; + + page_move_anon_rmap(page, vma); entry = pmd_mkyoung(orig_pmd); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); if (pmdp_set_access_flags(vma, haddr, vmf->pmd, entry, 1)) diff --git a/mm/memory.c b/mm/memory.c index 00c45b3a9576..7b32f422798d 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3307,6 +3307,7 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf) * and the page is locked, it's dark out, and we're wearing * sunglasses. Hit it. */ + page_move_anon_rmap(page, vma); unlock_page(page); wp_page_reuse(vmf); return VM_FAULT_WRITE;