From nobody Fri Dec 19 22:01:04 2025 Received: from mail-pf1-f173.google.com (mail-pf1-f173.google.com [209.85.210.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A05BC2375A for ; Thu, 18 Jan 2024 11:12:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705576367; cv=none; b=RJgC0rIF93fU42aT+Oi5zdcXf4L4+8hOHo/CktlHkMjE+erljvDi/LbvNidHwUQg/dlH+opSvsp+J3sUOCfCnb8gCBJa9xdg1PUdIMd3nZTIdLxMI1vXDlK8B1H/dYfKgJ1sPobCFGXuowi/+5efJBOCnqzsMs2XD93qTy4QQmw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705576367; c=relaxed/simple; bh=2rkgrzFdO6JMP0Th3YTAsnG21pW/6krZABLQ6XKuipI=; h=Received:DKIM-Signature:X-Google-DKIM-Signature: X-Gm-Message-State:X-Google-Smtp-Source:X-Received:Received:From: To:Cc:Subject:Date:Message-Id:X-Mailer:In-Reply-To:References: MIME-Version:Content-Transfer-Encoding; b=H2yZcbwUsFKHxfBzQJAGXrShR2lcX11zyrNW5UogYU+eSFysELfpKxSdg/hyseNcbG0xXOEhvO/SsrUI4LtnaaU0rwt4tJ1qUx0rHsptY+gAMVzuEH9LIdTyT9HrCTfHpJ1JwaszoCFMVVX1kHIwWhn306Lji5gejztX59noONs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=E6Zc89DB; arc=none smtp.client-ip=209.85.210.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="E6Zc89DB" Received: by mail-pf1-f173.google.com with SMTP id d2e1a72fcca58-6d9b37f4804so393869b3a.1 for ; Thu, 18 Jan 2024 03:12:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1705576365; x=1706181165; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=jPRbXml8IYd9XMbGDp/b9xmA+KUiJTFI45JekYQVHFk=; b=E6Zc89DB+LpEirh8qGL7egVvFVf7h8DvkEwutnAf+0Fa9stFOkmSFxbMEW5O1I5F4C VShy7uqCZiqqlM9w3mIBVWZYBhne1utH6uXxipBQKWElab1S3uwpbrVcO6InSP3qKEMm kizI+eeZmgKoOu0TetJaDBXqTNy22gzzfR/5fhON3uVRzP9trVTuzGOOcb8ta+YzDIpF MxJgvLbTQDUoz/WvJ8P9Vj6HfJyJaGenWJMnmwWwW484RXKSk+28I8Gh6w4lVscv8SdP 8ly1Is6DW7toDfqXVVHNodEHmdhgR0D2I/zumcaRcjSG7BrNMndbT7bveHb7jofZX+Hd m6jQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705576365; x=1706181165; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=jPRbXml8IYd9XMbGDp/b9xmA+KUiJTFI45JekYQVHFk=; b=Z7M5d4TN3dnu6kp+k8SQ2XowM762Aeo8sW0dcEbfo7pZf9vvjtXeeiMlgcwSUc/4mI j+InCj1j6t1i6rHjzrPYZdHYBCIykt5KKYY+aPHDs0WSBttQ1ds3r1WRuazmGSgjQlUi nbITmVed1QeatevGFRAe7b+rzEc+wNzRO2qBkUT5xhz4WHewSXFYDmBoV4/eregi7Uq/ fGv9HfKsmGiB1EgOfo507AH2XUR+q7opcECW8WCPv1QWv1WfsFENzGrJXwMlg9/+2I99 YlH47xKmV148OFJQ65CgeRCiBgVbbJtv5DRm6+YoIF9DrPjtB2rW0dTXW9ktOrWq+wbN 9JGw== X-Gm-Message-State: AOJu0YxPMCh6ue8UGID98rWVvn+mbXe3quvwBewVigokPNsDAIRwWydI Cb1YfEsmT08vFomEparx+lbr4ri/+aUzwv1h+13yzsJVJs+bLZEq X-Google-Smtp-Source: AGHT+IHPb2V5o+Kp/DcFse2JrVkm3MDRb3SQdSn4vIY2cU1g3ZhVG+tEV+84Z29sP1LjBn1UyzwA9g== X-Received: by 2002:a05:6a20:548b:b0:19a:fbfa:b16a with SMTP id i11-20020a056a20548b00b0019afbfab16amr1121941pzk.30.1705576364885; Thu, 18 Jan 2024 03:12:44 -0800 (PST) Received: from barry-desktop.. (143.122.224.49.dyn.cust.vf.net.nz. [49.224.122.143]) by smtp.gmail.com with ESMTPSA id t19-20020a056a0021d300b006d9be753ac7sm3039107pfj.108.2024.01.18.03.12.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Jan 2024 03:12:44 -0800 (PST) From: Barry Song <21cnbao@gmail.com> To: ryan.roberts@arm.com, akpm@linux-foundation.org, david@redhat.com, linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, mhocko@suse.com, shy828301@gmail.com, wangkefeng.wang@huawei.com, willy@infradead.org, xiang@kernel.org, ying.huang@intel.com, yuzhao@google.com, surenb@google.com, steven.price@arm.com, Chuanhua Han , Barry Song Subject: [PATCH RFC 6/6] mm: madvise: don't split mTHP for MADV_PAGEOUT Date: Fri, 19 Jan 2024 00:10:36 +1300 Message-Id: <20240118111036.72641-7-21cnbao@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240118111036.72641-1-21cnbao@gmail.com> References: <20231025144546.577640-1-ryan.roberts@arm.com> <20240118111036.72641-1-21cnbao@gmail.com> 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" From: Chuanhua Han MADV_PAGEOUT and MADV_FREE are common cases in Android. Ryan's patchset has supported swapping large folios out as a whole for vmscan case. This patch extends the feature to madvise. If madvised range covers the whole large folio, we don't split it. Otherwis= e, we still need to split it. This patch doesn't depend on ARM64's CONT-PTE, alternatively, it defines one helper named pte_range_cont_mapped() to check if all PTEs are contiguously mapped to a large folio. Signed-off-by: Chuanhua Han Co-developed-by: Barry Song Signed-off-by: Barry Song --- include/asm-generic/tlb.h | 10 +++++++ include/linux/pgtable.h | 60 +++++++++++++++++++++++++++++++++++++++ mm/madvise.c | 48 +++++++++++++++++++++++++++++++ 3 files changed, 118 insertions(+) diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 129a3a759976..f894e22da5d6 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -608,6 +608,16 @@ static inline void tlb_flush_p4d_range(struct mmu_gath= er *tlb, __tlb_remove_tlb_entry(tlb, ptep, address); \ } while (0) =20 +#define tlb_remove_nr_tlb_entry(tlb, ptep, address, nr) \ + do { \ + int i; \ + tlb_flush_pte_range(tlb, address, \ + PAGE_SIZE * nr); \ + for (i =3D 0; i < nr; i++) \ + __tlb_remove_tlb_entry(tlb, ptep + i, \ + address + i * PAGE_SIZE); \ + } while (0) + #define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \ do { \ unsigned long _sz =3D huge_page_size(h); \ diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 37fe83b0c358..da0c1cf447e3 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -320,6 +320,42 @@ static inline pgd_t pgdp_get(pgd_t *pgdp) } #endif =20 +#ifndef pte_range_cont_mapped +static inline bool pte_range_cont_mapped(unsigned long start_pfn, + pte_t *start_pte, + unsigned long start_addr, + int nr) +{ + int i; + pte_t pte_val; + + for (i =3D 0; i < nr; i++) { + pte_val =3D ptep_get(start_pte + i); + + if (pte_none(pte_val)) + return false; + + if (pte_pfn(pte_val) !=3D (start_pfn + i)) + return false; + } + + return true; +} +#endif + +#ifndef pte_range_young +static inline bool pte_range_young(pte_t *start_pte, int nr) +{ + int i; + + for (i =3D 0; i < nr; i++) + if (pte_young(ptep_get(start_pte + i))) + return true; + + return false; +} +#endif + #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long address, @@ -580,6 +616,23 @@ static inline pte_t ptep_get_and_clear_full(struct mm_= struct *mm, } #endif =20 +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_RANGE_FULL +static inline pte_t ptep_get_and_clear_range_full(struct mm_struct *mm, + unsigned long start_addr, + pte_t *start_pte, + int nr, int full) +{ + int i; + pte_t pte; + + pte =3D ptep_get_and_clear_full(mm, start_addr, start_pte, full); + + for (i =3D 1; i < nr; i++) + ptep_get_and_clear_full(mm, start_addr + i * PAGE_SIZE, + start_pte + i, full); + + return pte; +} =20 /* * If two threads concurrently fault at the same page, the thread that @@ -995,6 +1048,13 @@ static inline void arch_swap_restore(swp_entry_t entr= y, struct folio *folio) }) #endif =20 +#ifndef pte_nr_addr_end +#define pte_nr_addr_end(addr, size, end) \ +({ unsigned long __boundary =3D ((addr) + size) & (~(size - 1)); \ + (__boundary - 1 < (end) - 1)? __boundary: (end); \ +}) +#endif + /* * When walking page tables, we usually want to skip any p?d_none entries; * and any p?d_bad entries - reporting the error before resetting to none. diff --git a/mm/madvise.c b/mm/madvise.c index 912155a94ed5..262460ac4b2e 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -452,6 +452,54 @@ static int madvise_cold_or_pageout_pte_range(pmd_t *pm= d, if (folio_test_large(folio)) { int err; =20 + if (!folio_test_pmd_mappable(folio)) { + int nr_pages =3D folio_nr_pages(folio); + unsigned long folio_size =3D PAGE_SIZE * nr_pages; + unsigned long start_addr =3D ALIGN_DOWN(addr, nr_pages * PAGE_SIZE);; + unsigned long start_pfn =3D page_to_pfn(folio_page(folio, 0)); + pte_t *start_pte =3D pte - (addr - start_addr) / PAGE_SIZE; + unsigned long next =3D pte_nr_addr_end(addr, folio_size, end); + + if (!pte_range_cont_mapped(start_pfn, start_pte, start_addr, nr_pages)) + goto split; + + if (next - addr !=3D folio_size) { + goto split; + } else { + /* Do not interfere with other mappings of this page */ + if (folio_estimated_sharers(folio) !=3D 1) + goto skip; + + VM_BUG_ON(addr !=3D start_addr || pte !=3D start_pte); + + if (pte_range_young(start_pte, nr_pages)) { + ptent =3D ptep_get_and_clear_range_full(mm, start_addr, start_pte, + nr_pages, tlb->fullmm); + ptent =3D pte_mkold(ptent); + + set_ptes(mm, start_addr, start_pte, ptent, nr_pages); + tlb_remove_nr_tlb_entry(tlb, start_pte, start_addr, nr_pages); + } + + folio_clear_referenced(folio); + folio_test_clear_young(folio); + if (pageout) { + if (folio_isolate_lru(folio)) { + if (folio_test_unevictable(folio)) + folio_putback_lru(folio); + else + list_add(&folio->lru, &folio_list); + } + } else + folio_deactivate(folio); + } +skip: + pte +=3D (next - PAGE_SIZE - (addr & PAGE_MASK))/PAGE_SIZE; + addr =3D next - PAGE_SIZE; + continue; + + } +split: if (folio_estimated_sharers(folio) !=3D 1) break; if (pageout_anon_only_filter && !folio_test_anon(folio)) --=20 2.34.1