From patchwork Tue Mar 8 23:47:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yu Zhao X-Patchwork-Id: 12774495 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 36A8EC433EF for ; Tue, 8 Mar 2022 23:50:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=Gm/95t16MgUMAmf8l/oRi1urztMxytCFQP6XoRnyZqc=; b=A/qkVFCjg1wv02dUtRbFz+bIim GR/cPDtXEXrQowj08e+ApfIk8Lz2C4/eAwrnccPOIfTSOd98PZQ0ygoz431u6ZjdT3PoFdH1EzxFx rR2g7os0R/Su+y9evPH6GWCDfcGkMmpGohAKXCSpe2SVCaBtQAZJiDp0BcohQs7mrAHrAt7Paj9md VbaJSn6G0lbgPirHo8Aw0pLg7ZhTn3iVLhZZSyfWI+APY7wRKxzzCfsm4hyWrGoP3L09Y9Rjj2c43 Iul0ZboXJbqwf7SXQHIT3c+7h3vhOLfFuJOs9bXo6dI+M6mr4iAQh+tdY2bXhF1dolD8bzo6OAHtH zC/5QqVg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nRjZm-006acE-AQ; Tue, 08 Mar 2022 23:49:10 +0000 Received: from mail-yb1-xb4a.google.com ([2607:f8b0:4864:20::b4a]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nRjZ6-006aIA-SV for linux-arm-kernel@lists.infradead.org; Tue, 08 Mar 2022 23:48:30 +0000 Received: by mail-yb1-xb4a.google.com with SMTP id 190-20020a2505c7000000b00629283fec72so431786ybf.5 for ; Tue, 08 Mar 2022 15:48:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc:content-transfer-encoding; bh=Tgx8ae//L5IA0Yqg+D9TLCaQ78LCepfaB8sQmorTCkw=; b=VOKPAsZMw2EV5dnaXWEgHzcI5T7bLhbnjoKi9m50b58E08xYQ7AQ9wyvJWF/iwQD2i aBXNXX/+p5kssXAP/xEEA3iE4zfOV/rH1m4zIE6673YDm2JTUpG3vhISAhVnVF10BZDA er/lKNdTchIWlOMT8Mla52KvQtNMtEt9wsIyC6NF+oclvaI3bW05E/B9XEX9wmL4iINU f0EG9As4WkKNuXXMbHqrhPU6ANTfBbNNev1NL0Mo1YxqfJqgwfQb3+vzaKCEGigpkhUM 7XDGWwezEmMQZpnvkAmwolSIauMUP6Qkdgy7xp0FCmDnQsCgZGbAPTtAnZlTffldFHoW 8SkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc:content-transfer-encoding; bh=Tgx8ae//L5IA0Yqg+D9TLCaQ78LCepfaB8sQmorTCkw=; b=2Hlh5+xfJwem9t+nQlanjJ2yhCAbdB6oPtEkl4wjrNLBp26Fj2yVu+SxYEjID4QXml ojxAWV9HmI1MF2v7qOQ0swGzS7JoBCu2JFVzIH4HutBHPZrP86a7BZ8Jp58IWzujr+EQ V9FfbMs34Xioa5ScjUBAAFJH0lsyQ8wEkyGXPquvlaWT3yNCU4hnYFRowz65NiqdiJUT 4QjpQFFqJrXyZtLUUsCzIIFIOrKuL+J7hyPKagD17jX1rmUOEbRhp16uCOix4panCGe3 NcaaLcEd7JlKYVW869ngYWWkzPixu+H5m2DCqWYybTlmQ71PuycQ05uDWTBvx7iM3xfF hpNw== X-Gm-Message-State: AOAM531gWU/V8rl+LZ+Jj3QXRNT7McIM591XGcLxSuiugpAOUrF27mr2 DxGvvclbHhhqYLIcnGPvQNFDdKwQpDs= X-Google-Smtp-Source: ABdhPJzr/LkGrf4zyQbWc/3GKFRSRZHS+D+1l8yz6GSzSf+zXSNr/RBGB8TIrC/rAfzru4/+7Vn4wNwfMpY= X-Received: from yuzhao.bld.corp.google.com ([2620:15c:183:200:57a6:54a6:aad1:c0a8]) (user=yuzhao job=sendgmr) by 2002:a25:dd87:0:b0:628:e822:bd with SMTP id u129-20020a25dd87000000b00628e82200bdmr13462896ybg.505.1646783306798; Tue, 08 Mar 2022 15:48:26 -0800 (PST) Date: Tue, 8 Mar 2022 16:47:12 -0700 In-Reply-To: <20220308234723.3834941-1-yuzhao@google.com> Message-Id: <20220308234723.3834941-3-yuzhao@google.com> Mime-Version: 1.0 References: <20220308234723.3834941-1-yuzhao@google.com> X-Mailer: git-send-email 2.35.1.616.g0bdcbb4464-goog Subject: [PATCH v8 02/14] mm: x86: add CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG From: Yu Zhao To: Andrew Morton Cc: Andi Kleen , Aneesh Kumar , Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Linus Torvalds , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Mike Rapoport , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, x86@kernel.org, Yu Zhao , Brian Geffon , Jan Alexander Steffens , Oleksandr Natalenko , Steven Barrett , Suleiman Souhlal , Daniel Byrne , Donald Carr , " =?utf-8?q?Holger_Hoffst=C3=A4tte?= " , Konstantin Kharlamov , Shuang Zhai , Sofia Trinh , Vaibhav Jain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220308_154828_965344_8A8FA2FE X-CRM114-Status: GOOD ( 17.95 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Some architectures support the accessed bit in non-leaf PMD entries, e.g., x86 sets the accessed bit in a non-leaf PMD entry when using it as part of linear address translation [1]. Page table walkers that clear the accessed bit may use this capability to reduce their search space. Note that: 1. Although an inline function is preferable, this capability is added as a configuration option for consistency with the existing macros. 2. Due to the little interest in other varieties, this capability was only tested on Intel and AMD CPUs. [1]: Intel 64 and IA-32 Architectures Software Developer's Manual Volume 3 (June 2021), section 4.8 Signed-off-by: Yu Zhao Acked-by: Brian Geffon Acked-by: Jan Alexander Steffens (heftig) Acked-by: Oleksandr Natalenko Acked-by: Steven Barrett Acked-by: Suleiman Souhlal Tested-by: Daniel Byrne Tested-by: Donald Carr Tested-by: Holger Hoffstätte Tested-by: Konstantin Kharlamov Tested-by: Shuang Zhai Tested-by: Sofia Trinh Tested-by: Vaibhav Jain --- arch/Kconfig | 9 +++++++++ arch/x86/Kconfig | 1 + arch/x86/include/asm/pgtable.h | 3 ++- arch/x86/mm/pgtable.c | 5 ++++- include/linux/pgtable.h | 4 ++-- 5 files changed, 18 insertions(+), 4 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 678a80713b21..f9c59ecadbbb 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1322,6 +1322,15 @@ config DYNAMIC_SIGFRAME config HAVE_ARCH_NODE_DEV_GROUP bool +config ARCH_HAS_NONLEAF_PMD_YOUNG + bool + depends on PGTABLE_LEVELS > 2 + help + Architectures that select this option are capable of setting the + accessed bit in non-leaf PMD entries when using them as part of linear + address translations. Page table walkers that clear the accessed bit + may use this capability to reduce their search space. + source "kernel/gcov/Kconfig" source "scripts/gcc-plugins/Kconfig" diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 9f5bd41bf660..e787b7fc75be 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -85,6 +85,7 @@ config X86 select ARCH_HAS_PMEM_API if X86_64 select ARCH_HAS_PTE_DEVMAP if X86_64 select ARCH_HAS_PTE_SPECIAL + select ARCH_HAS_NONLEAF_PMD_YOUNG select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 select ARCH_HAS_COPY_MC if X86_64 select ARCH_HAS_SET_MEMORY diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 60b6ce45c2e3..f973788f6b21 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -819,7 +819,8 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) static inline int pmd_bad(pmd_t pmd) { - return (pmd_flags(pmd) & ~_PAGE_USER) != _KERNPG_TABLE; + return (pmd_flags(pmd) & ~(_PAGE_USER | _PAGE_ACCESSED)) != + (_KERNPG_TABLE & ~_PAGE_ACCESSED); } static inline unsigned long pages_to_mb(unsigned long npg) diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 3481b35cb4ec..a224193d84bf 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -550,7 +550,7 @@ int ptep_test_and_clear_young(struct vm_area_struct *vma, return ret; } -#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG) int pmdp_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmdp) { @@ -562,6 +562,9 @@ int pmdp_test_and_clear_young(struct vm_area_struct *vma, return ret; } +#endif + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE int pudp_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pud_t *pudp) { diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 79f64dcff07d..743e7fc4afda 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -212,7 +212,7 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, #endif #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG -#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG) static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp) @@ -233,7 +233,7 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, BUILD_BUG(); return 0; } -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */ #endif #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH