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 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 44EB5C7EE32 for ; Sat, 28 Jun 2025 11:47:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=V4dn6eClqZku968XieTCYkQsYAcGmcWWR4z8tKm4Ym8=; b=WmOY2DzrYzGhdfZ3g154Uzjmo0 B6QD0fOGMrCUuWX3KbEzaPEz/wP+QA8IVtO4LoqSpBTrSiZ1ffsrwZ9TtmIoaWjyiZLxJLOtZZTuC u4EFNIa2hvipw1mTr0WH8bL01DtBVGqIJRx111+CnxmJ8vP0+7oeAztmbzqKSJZi6foxCIbjjmUUE k8SDUkwlMu5WVVTLLGGxewhuiTCtvBkKb7yR+UWFEhdRkzKfL75mZzGj33ifq3bDcrwuDcJ13METc F/2r2+4IK6Wo0SiZ9zQRA7D+soHSnxKAqVJhVzJ5XVbr1nCQlbNTOvmcINwCNLt5BfdYu6p5LT4qz NT3tGPrw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uVU1H-0000000Gk01-3T4E; Sat, 28 Jun 2025 11:46:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uVTqL-0000000GjK8-0L5g for linux-arm-kernel@lists.infradead.org; Sat, 28 Jun 2025 11:35:38 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CF0401BD0; Sat, 28 Jun 2025 04:35:19 -0700 (PDT) Received: from MacBook-Pro.blr.arm.com (MacBook-Pro.blr.arm.com [10.164.18.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id F31033F762; Sat, 28 Jun 2025 04:35:28 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org Cc: ryan.roberts@arm.com, david@redhat.com, willy@infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, will@kernel.org, Liam.Howlett@oracle.com, lorenzo.stoakes@oracle.com, vbabka@suse.cz, jannh@google.com, anshuman.khandual@arm.com, peterx@redhat.com, joey.gouly@arm.com, ioworker0@gmail.com, baohua@kernel.org, kevin.brodsky@arm.com, quic_zhenhuah@quicinc.com, christophe.leroy@csgroup.eu, yangyicong@hisilicon.com, linux-arm-kernel@lists.infradead.org, hughd@google.com, yang@os.amperecomputing.com, ziy@nvidia.com, Dev Jain Subject: [PATCH v4 4/4] arm64: Add batched versions of ptep_modify_prot_start/commit Date: Sat, 28 Jun 2025 17:04:35 +0530 Message-Id: <20250628113435.46678-5-dev.jain@arm.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20250628113435.46678-1-dev.jain@arm.com> References: <20250628113435.46678-1-dev.jain@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250628_043537_234669_20C4DDBB X-CRM114-Status: GOOD ( 14.38 ) 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 Override the generic definition of modify_prot_start_ptes() to use get_and_clear_full_ptes(). This helper does a TLBI only for the starting and ending contpte block of the range, whereas the current implementation will call ptep_get_and_clear() for every contpte block, thus doing a TLBI on every contpte block. Therefore, we have a performance win. The arm64 definition of pte_accessible() allows us to batch in the errata specific case: #define pte_accessible(mm, pte) \ (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte)) All ptes are obviously present in the folio batch, and they are also valid. Override the generic definition of modify_prot_commit_ptes() to simply use set_ptes() to map the new ptes into the pagetable. Signed-off-by: Dev Jain --- arch/arm64/include/asm/pgtable.h | 10 ++++++++++ arch/arm64/mm/mmu.c | 28 +++++++++++++++++++++++----- 2 files changed, 33 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index ba63c8736666..abd2dee416b3 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -1643,6 +1643,16 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t old_pte, pte_t new_pte); +#define modify_prot_start_ptes modify_prot_start_ptes +extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + unsigned int nr); + +#define modify_prot_commit_ptes modify_prot_commit_ptes +extern void modify_prot_commit_ptes(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep, pte_t old_pte, pte_t pte, + unsigned int nr); + #ifdef CONFIG_ARM64_CONTPTE /* diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 3d5fb37424ab..38325616f467 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -1524,24 +1525,41 @@ static int __init prevent_bootmem_remove_init(void) early_initcall(prevent_bootmem_remove_init); #endif -pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) +pte_t modify_prot_start_ptes(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep, unsigned int nr) { + pte_t pte = get_and_clear_full_ptes(vma->vm_mm, addr, ptep, nr, 0); + if (alternative_has_cap_unlikely(ARM64_WORKAROUND_2645198)) { /* * Break-before-make (BBM) is required for all user space mappings * when the permission changes from executable to non-executable * in cases where cpu is affected with errata #2645198. */ - if (pte_user_exec(ptep_get(ptep))) - return ptep_clear_flush(vma, addr, ptep); + if (pte_accessible(vma->vm_mm, pte) && pte_user_exec(pte)) + __flush_tlb_range(vma, addr, nr * PAGE_SIZE, + PAGE_SIZE, true, 3); } - return ptep_get_and_clear(vma->vm_mm, addr, ptep); + + return pte; +} + +pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) +{ + return modify_prot_start_ptes(vma, addr, ptep, 1); +} + +void modify_prot_commit_ptes(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep, pte_t old_pte, pte_t pte, + unsigned int nr) +{ + set_ptes(vma->vm_mm, addr, ptep, pte, nr); } void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t old_pte, pte_t pte) { - set_pte_at(vma->vm_mm, addr, ptep, pte); + modify_prot_commit_ptes(vma, addr, ptep, old_pte, pte, 1); } /* -- 2.30.2