From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E72F148123D for ; Wed, 29 Jul 2026 12:25:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785327945; cv=none; b=JzhuLIx5tkR5jl2GTaoYmqrociElqyj/UIS/bY49iS4hCCGiNCvozR0OvbN8sXtiwCFZUJipWE1yEDcnsNntfOWb57D4+wWx46ptdK0q7MFnSefUQIgrJmAuH+C6BVdoEJt65lMOU6ND9JjtLXIX0nRk33aVpmlcnnnWn1gXYiI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785327945; c=relaxed/simple; bh=D8njUR+w2v+ndiG5KM/iOINKA++RZQNA50z7qf0KbP8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mXXUAJbPgQibh9xXDlJIQXrHbzwqU2siz1BLn0lsbuIavxebFXaXU9KYxskD+SB6gbUn0aofTGdx14ZULUB8QIveD4GPJgfRjg+2BIZTzLH1Z8Hhzgj27pvalAx4L39DIcyODVeFp3PMcaHef3Pn2ScxpQnJjEVYZQBkAzcV038= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=q69ENXoq; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="q69ENXoq" 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 3B0FC1688; Wed, 29 Jul 2026 05:25:38 -0700 (PDT) Received: from a085714.blr.arm.com (a085714.arm.com [10.164.19.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B7CA03F66F; Wed, 29 Jul 2026 05:25:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1785327942; bh=D8njUR+w2v+ndiG5KM/iOINKA++RZQNA50z7qf0KbP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q69ENXoqiIBHn6/l0E0y3VJVTEIxcaEzGpXLTpzhhxWEKiil8Yl0wkGY729L3ibAE sTDaFsU7xMGX3Dm+zHJOAIH7WcqYS+s+vXMCmS28R43/go9/2y2fkWdkIKAmC5s7KO Y4yezjZos5Gr+KnmpMA+33p7DaNp9fDrFTbev4xc= From: Anshuman Khandual To: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Ryan Roberts , Mark Rutland , Lorenzo Stoakes , Andrew Morton , David Hildenbrand , Mike Rapoport , Linu Cherian , linux-kernel@vger.kernel.org Subject: [PATCH 08/17] arm64/mm: Route all pgtable atomics to central helpers Date: Wed, 29 Jul 2026 17:54:43 +0530 Message-ID: <20260729122452.3797443-9-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260729122452.3797443-1-anshuman.khandual@arm.com> References: <20260729122452.3797443-1-anshuman.khandual@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Route all cmpxchg() operations performed on various page table entries to a new ptval_cmpxchg_relaxed() helper. Similarly route all xchg() operations performed on page table entries to a new ptval_xchg_relaxed() helper. Currently these helpers just forward to the same APIs that were previously called direct, but in future we will change the routing for D128 which is too long to use the standard APIs. Cc: Catalin Marinas Cc: Will Deacon Cc: Ryan Roberts Cc: Mark Rutland Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- arch/arm64/include/asm/pgtable.h | 26 +++++++++++++++++++------- arch/arm64/mm/fault.c | 2 +- 2 files changed, 20 insertions(+), 8 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 1106977e0ef0..4efcacec6f01 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -87,6 +87,17 @@ static inline void arch_leave_lazy_mmu_mode(void) #define ptval_get(x) READ_ONCE(x) #define ptval_set(x, val) WRITE_ONCE(x, val) +static inline ptval_t ptval_cmpxchg_relaxed(ptval_t *ptep, ptval_t old, + ptval_t new) +{ + return cmpxchg_relaxed(ptep, old, new); +} + +static inline ptval_t ptval_xchg_relaxed(ptval_t *ptep, ptval_t new) +{ + return xchg_relaxed(ptep, new); +} + #define pmdp_get pmdp_get static inline pmd_t pmdp_get(pmd_t *pmdp) { @@ -1340,8 +1351,8 @@ static inline bool __ptep_test_and_clear_young(struct vm_area_struct *vma, do { old_pte = pte; pte = pte_mkold(pte); - pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), - pte_val(old_pte), pte_val(pte)); + pte_val(pte) = ptval_cmpxchg_relaxed(&pte_val(*ptep), + pte_val(old_pte), pte_val(pte)); } while (pte_val(pte) != pte_val(old_pte)); return pte_young(pte); @@ -1383,7 +1394,7 @@ static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm, pte_t *ptep, unsigned long pgsize) { - pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0)); + pte_t pte = __pte(ptval_xchg_relaxed(&pte_val(*ptep), 0)); switch (pgsize) { case PAGE_SIZE: @@ -1459,7 +1470,7 @@ static inline void ___ptep_set_wrprotect(struct mm_struct *mm, do { old_pte = pte; pte = pte_wrprotect(pte); - pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), + pte_val(pte) = ptval_cmpxchg_relaxed(&pte_val(*ptep), pte_val(old_pte), pte_val(pte)); } while (pte_val(pte) != pte_val(old_pte)); } @@ -1497,7 +1508,7 @@ static inline void __clear_young_dirty_pte(struct vm_area_struct *vma, if (flags & CYDP_CLEAR_DIRTY) pte = pte_mkclean(pte); - pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), + pte_val(pte) = ptval_cmpxchg_relaxed(&pte_val(*ptep), pte_val(old_pte), pte_val(pte)); } while (pte_val(pte) != pte_val(old_pte)); } @@ -1536,7 +1547,7 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp, pmd_t pmd) { page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd); - return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); + return __pmd(ptval_xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); } #endif @@ -1863,7 +1874,8 @@ static inline bool ptep_try_set(pte_t *ptep, pte_t new_pte) { pteval_t old = 0; - if (!try_cmpxchg(&pte_val(*ptep), &old, pte_val(new_pte))) + old = ptval_cmpxchg_relaxed(&pte_val(*ptep), old, pte_val(new_pte)); + if (old != 0) return false; /* diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index fca716ed4513..7aff70c5479e 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -234,7 +234,7 @@ int __ptep_set_access_flags_anysz(struct vm_area_struct *vma, pteval ^= PTE_RDONLY; pteval |= pte_val(entry); pteval ^= PTE_RDONLY; - pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); + pteval = ptval_cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); } while (pteval != old_pteval); /* -- 2.43.0