From nobody Sun Apr 5 21:17:38 2026 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E6209371D02 for ; Fri, 6 Mar 2026 06:44:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.130 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772779458; cv=none; b=pw6Omj+PbBaPuhZEKnbLvB3P39gFjhcvfbQV1I45PaG85NhmYZIvwN9qvbqnPlZQYijjOj5m6EhzeEE8FAHKG8Hr+YxoyInbs3jpgFtmEYGyTHkHJptUz4BvpESdxzbhSAlERLNoGymz2UBQONcB/I+/9xj/d+6/EY4rl0vPx68= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772779458; c=relaxed/simple; bh=xQSoH8Ux9Ilv+cYOKrx/tHuqnVK+e+Pu2dYDUnQwH7c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hZfBV82EXeJpVFBvx+YStVW9ZCqDYXBdBc1vcaxlpQ9/ftNhgY8t/VYLKYP1gQPT2wd8ZdlzPleFIKLC/2TGLI2cTRxvKq3r5VObC2o3L/IXzcd9utoLn9tPpmQ29gvicfv2ZErTg1SOuahmaqjY8LxqL30Z0hHJcqgb3l8M8Uk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=ldKEC1ku; arc=none smtp.client-ip=115.124.30.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="ldKEC1ku" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1772779449; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=Z89VjCPOsBTAMzdOkBmmkyGLdD2D9prjOEPgmVbdWLg=; b=ldKEC1kuEPefnGMQ0yMTEQcsEED3mzCE7wZNbXSwW1u68p0NJHbxPyti4ErvsJCWWhefAlAODcEbZCNX4j/CFim370d0SPCIFr9n0IUIyL1FOabEkiX00obEKXDTp0QE3TC1+qtXfQbd+KQ1FthHOj4zDeAKmZK5wiHG4IoC0eM= Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0X-MLT6U_1772779446 cluster:ay36) by smtp.aliyun-inc.com; Fri, 06 Mar 2026 14:44:07 +0800 From: Baolin Wang To: akpm@linux-foundation.org, david@kernel.org Cc: catalin.marinas@arm.com, will@kernel.org, lorenzo.stoakes@oracle.com, ryan.roberts@arm.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, riel@surriel.com, harry.yoo@oracle.com, jannh@google.com, willy@infradead.org, baohua@kernel.org, dev.jain@arm.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, hannes@cmpxchg.org, zhengqi.arch@bytedance.com, shakeel.butt@linux.dev, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 6/6] arm64: mm: implement the architecture-specific test_and_clear_young_ptes() Date: Fri, 6 Mar 2026 14:43:42 +0800 Message-ID: <7f891d42a720cc2e57862f3b79e4f774404f313c.1772778858.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Implement the Arm64 architecture-specific test_and_clear_young_ptes() to en= able batched checking of young flags, improving performance during large folio reclamation when MGLRU is enabled. While we're at it, simplify ptep_test_and_clear_young() by calling test_and_clear_young_ptes(). Since callers guarantee that PTEs are present before calling these functions, we can use pte_cont() to check the CONT_PTE flag instead of pte_valid_cont(). Performance testing: Enable MGLRU, then allocate 10G clean file-backed folios by mmap() in a mem= ory cgroup, and try to reclaim 8G file-backed folios via the memory.reclaim int= erface. I can observe 60%+ performance improvement on my Arm64 32-core server (and = about 15% improvement on my X86 machine). W/o patchset: real 0m0.470s user 0m0.000s sys 0m0.470s W/ patchset: real 0m0.180s user 0m0.001s sys 0m0.179s Reviewed-by: Rik van Riel Signed-off-by: Baolin Wang Reviewed-by: David Hildenbrand (Arm) --- arch/arm64/include/asm/pgtable.h | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgta= ble.h index aa4b13da6371..ab451d20e4c5 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -1812,16 +1812,22 @@ static inline pte_t ptep_get_and_clear(struct mm_st= ruct *mm, return __ptep_get_and_clear(mm, addr, ptep); } =20 +#define test_and_clear_young_ptes test_and_clear_young_ptes +static inline int test_and_clear_young_ptes(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + unsigned int nr) +{ + if (likely(nr =3D=3D 1 && !pte_cont(__ptep_get(ptep)))) + return __ptep_test_and_clear_young(vma, addr, ptep); + + return contpte_test_and_clear_young_ptes(vma, addr, ptep, nr); +} + #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { - pte_t orig_pte =3D __ptep_get(ptep); - - if (likely(!pte_valid_cont(orig_pte))) - return __ptep_test_and_clear_young(vma, addr, ptep); - - return contpte_test_and_clear_young_ptes(vma, addr, ptep, 1); + return test_and_clear_young_ptes(vma, addr, ptep, 1); } =20 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH --=20 2.47.3