From patchwork Thu Apr 7 03:15:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yu Zhao X-Patchwork-Id: 12804403 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 C7614C433EF for ; Thu, 7 Apr 2022 03:24:36 +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=12oq7N04isD9e/yVfvYCcOfZt4/AMbW7ZHxZnR2FnB0=; b=mHFpHm83hpsvF/a1wOee0qwGEz FcSWYt8fPWzNp7bNACNmv5reCgMkJqTR9spFd0qoZTcnqrjHHNcC8tTsMjw3kOqQ2oaJT74YIMt74 L7sD1SJZYGZqH6Vg9tue7w6/stRuxtAaIew2jGg3iDuOv1qmZmTbu8PhizWS5hrQRkbJMSbyz452i k588qBpVoDAf5Tzw8jnclcKt9Yy0iwxGKlRo/hyTuZcnJnBQE1SmcGQ0uIU1707KpsMOi0L7GnCqN qlK5i6uIOqlJMKRIK774PuOo04Gfkz1wpGB6Zv5O4XlSKdiqZBedM4+T0CR7OnHj+ihY+wnjyQu+a oC2UJYzQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncIjU-0094D4-Hs; Thu, 07 Apr 2022 03:22:55 +0000 Received: from mail-yw1-x114a.google.com ([2607:f8b0:4864:20::114a]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncIcs-0091WU-8g for linux-arm-kernel@lists.infradead.org; Thu, 07 Apr 2022 03:16:05 +0000 Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2eba0a01619so38762857b3.3 for ; Wed, 06 Apr 2022 20:16:00 -0700 (PDT) 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=FWe6u7OxGl8de8Vu9oRQ5PKRSCE2puMlG1t8w1/uDnQ=; b=WR93aD7X9rdrM1L549SFrOF0eKr4CYwr8DK3+q/aNPDgM028OE8yMRDfWaIY1X02As iAQj6E791rgRA8Orr2aYSowVc6Ub7MmTt6d7k7Xx6EAkCaLAR9KF0X6/TC3QqB0XUasl kGS2p7Cx6tuCGpH2Bpz+CHPEmGW75jNKLdjFgtW5Fr6fGTcgOLWRjAdOaMHHZHoK0L+/ 9TiSjCffsSo2iwCpxtWQt22GgS35HuPzP70A2SjNuBUvv9GPZmlGqI7+nutLoEOQhITR hFoCdTFWD4TkrkC/gAfRvEjyCvwcUe922Sn+qzecfrb8ollYEo9XR0wsG/7wR4OOia7X H9Zg== 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=FWe6u7OxGl8de8Vu9oRQ5PKRSCE2puMlG1t8w1/uDnQ=; b=5WadDFbDM81/bhujTGAwaX9ZtHpa8+8+Ld+PRq1BIXQLmgja+6iFsEtw2w9ijbH+DS vE5V2gOm8Y20TVISNYIFKlWGuPy1t4rWN+Xd46EJuGczcFt5tz0cKWRS6EvJyCw/1CEz 9OnQBogAftXITc2KrJytnuRvlJCIvjIWnQQ0ZeI7W853kcFBzjhD1N8uEeWxS2xSsQjc 6vKHpI1e++Lotwz9//l5T3fnRRd5d6h1tQi2BqKNzJJSRTCf+eIu5BZna2Lp/BywrBFG Mik5z0Azh52io2CmTyWF2YonQyX74SxdlY1uSQ6R/a1hCoD/WgFoKwpT5q/5EkWZrYUU 0uMg== X-Gm-Message-State: AOAM530Q6njiqnGJ5xRtwERUNtv7PNSPWAUkjK277HghfgnyShM/YdT6 GjONTT6mem20XvFvpQMhUj/VBX05pSQ= X-Google-Smtp-Source: ABdhPJxxlAyKVArEY6lk1OhN84/NsJ+dG+rwxEtEW1ed206icTMUhyuixuUuC/TYxkExcsV++1O/an7s52g= X-Received: from yuzhao.bld.corp.google.com ([2620:15c:183:200:9ea2:c755:ae22:6862]) (user=yuzhao job=sendgmr) by 2002:a25:6642:0:b0:633:b9f4:b57d with SMTP id z2-20020a256642000000b00633b9f4b57dmr8465254ybm.394.1649301359983; Wed, 06 Apr 2022 20:15:59 -0700 (PDT) Date: Wed, 6 Apr 2022 21:15:14 -0600 In-Reply-To: <20220407031525.2368067-1-yuzhao@google.com> Message-Id: <20220407031525.2368067-3-yuzhao@google.com> Mime-Version: 1.0 References: <20220407031525.2368067-1-yuzhao@google.com> X-Mailer: git-send-email 2.35.1.1094.g7c7d902a7c-goog Subject: [PATCH v10 02/14] mm: x86: add CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG From: Yu Zhao To: Stephen Rothwell , linux-mm@kvack.org Cc: Andi Kleen , Andrew Morton , Aneesh Kumar , Barry Song <21cnbao@gmail.com>, 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, page-reclaim@google.com, x86@kernel.org, Yu Zhao , Barry Song , 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-20220406_201602_441386_3C8FD0DB X-CRM114-Status: GOOD ( 16.82 ) 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 Reviewed-by: Barry Song 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 29b0167c088b..c626bed3553d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1378,6 +1378,15 @@ 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 b0142e01002e..42c84e1ad73f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -86,6 +86,7 @@ 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 016606a0cf20..9cb3cf4cf6dd 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -820,7 +820,8 @@ 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