From nobody Mon Feb 9 05:52:38 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E349C7EE23 for ; Mon, 22 May 2023 05:03:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231681AbjEVFDP (ORCPT ); Mon, 22 May 2023 01:03:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231674AbjEVFDL (ORCPT ); Mon, 22 May 2023 01:03:11 -0400 Received: from mail-yb1-xb2a.google.com (mail-yb1-xb2a.google.com [IPv6:2607:f8b0:4864:20::b2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8433E9 for ; Sun, 21 May 2023 22:03:10 -0700 (PDT) Received: by mail-yb1-xb2a.google.com with SMTP id 3f1490d57ef6-ba86ea269e0so7904390276.1 for ; Sun, 21 May 2023 22:03:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1684731790; x=1687323790; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=W3t6elq9R4Rh1GonIcnIp9HMVNr0t0fb96tM78h+6lY=; b=Kc//GQWtdcYt13ahGjffwsLxy+Q5bVB6WROYwiSc3JojtgWwDe3izjSyHuE6U0IG/O 5Fry5zLgCWeTO19pC/0eYwlnvGNsyrmto6ZIBbyVNO56nsRvrMOAOUvYspI147xhZOi+ xqdX2iixj9Eo1KLPuK7IDQx9rj9ZoPh6D5XKx6tya/9I/bhzim+Yk6xTIzKBifA2beI4 8qMCGwFCGRwoHjLeW/d0tZsZvr4CJThANuX9SXUFpqX1pEid4ilFDqnQwxhHJZTeMBQb PwATHquSI9R4s4VAZXrMlE6dKgd4X76gX9zjTUT4KksMHQf4ahMKcn/OqGVTbmF1mVyt 4G7w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684731790; x=1687323790; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=W3t6elq9R4Rh1GonIcnIp9HMVNr0t0fb96tM78h+6lY=; b=IN6gI94sVKJiUeDaC112dAJZ5TO/WkIGwL46DZwmZdrFTSkTu+fufGXiAEXOFKW06g VhjUss3ciLF9Y38n+dvjZgRLltne/dGeLO7SUmv8s/xyQk/vwcFMQBT70+Dbxk87gYaV AM1J9gm8EL4GofkwVNRV1G8wq5ZU+E/EWdQkSShy8wv+nY0DeYUHnq8XyhB6QJffDeS+ yTJlr11aGB1dtMKZmvWZikIW5uEJuYPeib/ESWCC0z6yhbhAfzTvfOVh7fEpLDszPObt SB4GxVZbOPZkCahO71apgufy6uiBdRIdBRlosUZbC31Qo3toAVmSLjfw9/cjII2r+RE+ f2SA== X-Gm-Message-State: AC+VfDyX33BbhhZOChB31JfOJhlTgNQX6RX50bFffpVUrx4WkYsg45ox nEEvhoBeY5bFad1pJgsiAnaW3Q== X-Google-Smtp-Source: ACHHUZ6OdnTYy1GhoQl2g/GfXGTjIkyQzrSYRsCypiToKGf2HILo2risNfGACl3kmPaMyL1d5bYIVQ== X-Received: by 2002:a25:aaac:0:b0:bab:eb8b:c484 with SMTP id t41-20020a25aaac000000b00babeb8bc484mr2926154ybi.14.1684731789855; Sun, 21 May 2023 22:03:09 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id e6-20020a25b046000000b00ba73c26f0d6sm1322602ybj.15.2023.05.21.22.03.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 21 May 2023 22:03:09 -0700 (PDT) Date: Sun, 21 May 2023 22:03:06 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Andrew Morton cc: Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , Matthew Wilcox , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Yang Shi , Mel Gorman , Peter Xu , Peter Zijlstra , Will Deacon , Yu Zhao , Alistair Popple , Ralph Campbell , Ira Weiny , Steven Price , SeongJae Park , Naoya Horiguchi , Christophe Leroy , Zack Rusin , Jason Gunthorpe , Axel Rasmussen , Anshuman Khandual , Pasha Tatashin , Miaohe Lin , Minchan Kim , Christoph Hellwig , Song Liu , Thomas Hellstrom , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 11/31] mm/vmwgfx: simplify pmd & pud mapping dirty helpers In-Reply-To: <68a97fbe-5c1e-7ac6-72c-7b9c6290b370@google.com> Message-ID: References: <68a97fbe-5c1e-7ac6-72c-7b9c6290b370@google.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" wp_clean_pmd_entry() need not check pmd_trans_unstable() or pmd_none(), wp_clean_pud_entry() need not check pud_trans_unstable() or pud_none(): it's just the ACTION_CONTINUE when trans_huge or devmap that's needed to prevent splitting, and we're hoping to remove pmd_trans_unstable(). Is that PUD #ifdef necessary? Maybe some configs are missing a stub. Signed-off-by: Hugh Dickins --- mm/mapping_dirty_helpers.c | 34 +++++++++------------------------- 1 file changed, 9 insertions(+), 25 deletions(-) diff --git a/mm/mapping_dirty_helpers.c b/mm/mapping_dirty_helpers.c index e1eb33f49059..87b4beeda4fa 100644 --- a/mm/mapping_dirty_helpers.c +++ b/mm/mapping_dirty_helpers.c @@ -128,19 +128,11 @@ static int wp_clean_pmd_entry(pmd_t *pmd, unsigned lo= ng addr, unsigned long end, { pmd_t pmdval =3D pmdp_get_lockless(pmd); =20 - if (!pmd_trans_unstable(&pmdval)) - return 0; - - if (pmd_none(pmdval)) { - walk->action =3D ACTION_AGAIN; - return 0; - } - - /* Huge pmd, present or migrated */ - walk->action =3D ACTION_CONTINUE; - if (pmd_trans_huge(pmdval) || pmd_devmap(pmdval)) + /* Do not split a huge pmd, present or migrated */ + if (pmd_trans_huge(pmdval) || pmd_devmap(pmdval)) { WARN_ON(pmd_write(pmdval) || pmd_dirty(pmdval)); - + walk->action =3D ACTION_CONTINUE; + } return 0; } =20 @@ -156,23 +148,15 @@ static int wp_clean_pmd_entry(pmd_t *pmd, unsigned lo= ng addr, unsigned long end, static int wp_clean_pud_entry(pud_t *pud, unsigned long addr, unsigned lon= g end, struct mm_walk *walk) { +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD pud_t pudval =3D READ_ONCE(*pud); =20 - if (!pud_trans_unstable(&pudval)) - return 0; - - if (pud_none(pudval)) { - walk->action =3D ACTION_AGAIN; - return 0; - } - -#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD - /* Huge pud */ - walk->action =3D ACTION_CONTINUE; - if (pud_trans_huge(pudval) || pud_devmap(pudval)) + /* Do not split a huge pud */ + if (pud_trans_huge(pudval) || pud_devmap(pudval)) { WARN_ON(pud_write(pudval) || pud_dirty(pudval)); + walk->action =3D ACTION_CONTINUE; + } #endif - return 0; } =20 --=20 2.35.3