From: Will Deacon <will@kernel.org> To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, Will Deacon <will@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Jan Kara <jack@suse.cz>, Minchan Kim <minchan@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Linus Torvalds <torvalds@linux-foundation.org>, Vinayak Menon <vinmenon@codeaurora.org>, Hugh Dickins <hughd@google.com>, Nick Desaulniers <ndesaulniers@google.com>, kernel-team@android.com Subject: [PATCH v4 6/8] mm: Avoid modifying vmf.address in __collapse_huge_page_swapin() Date: Wed, 20 Jan 2021 17:36:10 +0000 [thread overview] Message-ID: <20210120173612.20913-7-will@kernel.org> (raw) In-Reply-To: <20210120173612.20913-1-will@kernel.org> In preparation for const-ifying the anonymous struct field of 'struct vm_fault', rework __collapse_huge_page_swapin() to avoid continuously updating vmf.address and instead populate a new 'struct vm_fault' on the stack for each page being processed. Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will@kernel.org> --- mm/khugepaged.c | 37 ++++++++++++++++++------------------- 1 file changed, 18 insertions(+), 19 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 67ab391a5373..fb0fdaec34d5 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -991,38 +991,41 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address, static bool __collapse_huge_page_swapin(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, pmd_t *pmd, + unsigned long haddr, pmd_t *pmd, int referenced) { int swapped_in = 0; vm_fault_t ret = 0; - struct vm_fault vmf = { - .vma = vma, - .address = address, - .flags = FAULT_FLAG_ALLOW_RETRY, - .pmd = pmd, - .pgoff = linear_page_index(vma, address), - }; - - vmf.pte = pte_offset_map(pmd, address); - for (; vmf.address < address + HPAGE_PMD_NR*PAGE_SIZE; - vmf.pte++, vmf.address += PAGE_SIZE) { + unsigned long address, end = haddr + (HPAGE_PMD_NR * PAGE_SIZE); + + for (address = haddr; address < end; address += PAGE_SIZE) { + struct vm_fault vmf = { + .vma = vma, + .address = address, + .pgoff = linear_page_index(vma, haddr), + .flags = FAULT_FLAG_ALLOW_RETRY, + .pmd = pmd, + }; + + vmf.pte = pte_offset_map(pmd, address); vmf.orig_pte = *vmf.pte; - if (!is_swap_pte(vmf.orig_pte)) + if (!is_swap_pte(vmf.orig_pte)) { + pte_unmap(vmf.pte); continue; + } swapped_in++; ret = do_swap_page(&vmf); /* do_swap_page returns VM_FAULT_RETRY with released mmap_lock */ if (ret & VM_FAULT_RETRY) { mmap_read_lock(mm); - if (hugepage_vma_revalidate(mm, address, &vmf.vma)) { + if (hugepage_vma_revalidate(mm, haddr, &vma)) { /* vma is no longer available, don't continue to swapin */ trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } /* check if the pmd is still valid */ - if (mm_find_pmd(mm, address) != pmd) { + if (mm_find_pmd(mm, haddr) != pmd) { trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } @@ -1031,11 +1034,7 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } - /* pte is unmapped now, we need to map it */ - vmf.pte = pte_offset_map(pmd, vmf.address); } - vmf.pte--; - pte_unmap(vmf.pte); /* Drain LRU add pagevec to remove extra pin on the swapped in pages */ if (swapped_in) -- 2.30.0.284.gd98b1dd5eaa7-goog
WARNING: multiple messages have this Message-ID (diff)
From: Will Deacon <will@kernel.org> To: linux-kernel@vger.kernel.org Cc: Nick Desaulniers <ndesaulniers@google.com>, kernel-team@android.com, Jan Kara <jack@suse.cz>, Minchan Kim <minchan@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Linus Torvalds <torvalds@linux-foundation.org>, Hugh Dickins <hughd@google.com>, linux-mm@kvack.org, Vinayak Menon <vinmenon@codeaurora.org>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Andrew Morton <akpm@linux-foundation.org>, Will Deacon <will@kernel.org>, linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 6/8] mm: Avoid modifying vmf.address in __collapse_huge_page_swapin() Date: Wed, 20 Jan 2021 17:36:10 +0000 [thread overview] Message-ID: <20210120173612.20913-7-will@kernel.org> (raw) In-Reply-To: <20210120173612.20913-1-will@kernel.org> In preparation for const-ifying the anonymous struct field of 'struct vm_fault', rework __collapse_huge_page_swapin() to avoid continuously updating vmf.address and instead populate a new 'struct vm_fault' on the stack for each page being processed. Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will@kernel.org> --- mm/khugepaged.c | 37 ++++++++++++++++++------------------- 1 file changed, 18 insertions(+), 19 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 67ab391a5373..fb0fdaec34d5 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -991,38 +991,41 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address, static bool __collapse_huge_page_swapin(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, pmd_t *pmd, + unsigned long haddr, pmd_t *pmd, int referenced) { int swapped_in = 0; vm_fault_t ret = 0; - struct vm_fault vmf = { - .vma = vma, - .address = address, - .flags = FAULT_FLAG_ALLOW_RETRY, - .pmd = pmd, - .pgoff = linear_page_index(vma, address), - }; - - vmf.pte = pte_offset_map(pmd, address); - for (; vmf.address < address + HPAGE_PMD_NR*PAGE_SIZE; - vmf.pte++, vmf.address += PAGE_SIZE) { + unsigned long address, end = haddr + (HPAGE_PMD_NR * PAGE_SIZE); + + for (address = haddr; address < end; address += PAGE_SIZE) { + struct vm_fault vmf = { + .vma = vma, + .address = address, + .pgoff = linear_page_index(vma, haddr), + .flags = FAULT_FLAG_ALLOW_RETRY, + .pmd = pmd, + }; + + vmf.pte = pte_offset_map(pmd, address); vmf.orig_pte = *vmf.pte; - if (!is_swap_pte(vmf.orig_pte)) + if (!is_swap_pte(vmf.orig_pte)) { + pte_unmap(vmf.pte); continue; + } swapped_in++; ret = do_swap_page(&vmf); /* do_swap_page returns VM_FAULT_RETRY with released mmap_lock */ if (ret & VM_FAULT_RETRY) { mmap_read_lock(mm); - if (hugepage_vma_revalidate(mm, address, &vmf.vma)) { + if (hugepage_vma_revalidate(mm, haddr, &vma)) { /* vma is no longer available, don't continue to swapin */ trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } /* check if the pmd is still valid */ - if (mm_find_pmd(mm, address) != pmd) { + if (mm_find_pmd(mm, haddr) != pmd) { trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } @@ -1031,11 +1034,7 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } - /* pte is unmapped now, we need to map it */ - vmf.pte = pte_offset_map(pmd, vmf.address); } - vmf.pte--; - pte_unmap(vmf.pte); /* Drain LRU add pagevec to remove extra pin on the swapped in pages */ if (swapped_in) -- 2.30.0.284.gd98b1dd5eaa7-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-01-20 17:42 UTC|newest] Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-01-20 17:36 [PATCH v4 0/8] Create 'old' ptes for faultaround mappings on arm64 with hardware access flag Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 1/8] mm: Cleanup faultaround and finish_fault() codepaths Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 2/8] mm: Allow architectures to request 'old' entries when prefaulting Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 3/8] arm64: mm: Implement arch_wants_old_prefaulted_pte() Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 4/8] mm: Move immutable fields of 'struct vm_fault' into anonymous struct Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 18:13 ` Nick Desaulniers 2021-01-20 18:13 ` Nick Desaulniers 2021-01-20 18:13 ` Nick Desaulniers 2021-01-21 12:48 ` Will Deacon 2021-01-21 12:48 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 5/8] mm: Pass 'address' to map to do_set_pte() and drop FAULT_FLAG_PREFAULT Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 17:36 ` Will Deacon [this message] 2021-01-20 17:36 ` [PATCH v4 6/8] mm: Avoid modifying vmf.address in __collapse_huge_page_swapin() Will Deacon 2021-01-20 17:36 ` [PATCH v4 7/8] mm: Use static initialisers for immutable fields of 'struct vm_fault' Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 18:21 ` Nick Desaulniers 2021-01-20 18:21 ` Nick Desaulniers 2021-01-20 18:21 ` Nick Desaulniers 2021-01-21 12:50 ` Will Deacon 2021-01-21 12:50 ` Will Deacon 2021-01-20 17:36 ` [PATCH v4 8/8] mm: Mark anonymous struct field of 'struct vm_fault' as 'const' Will Deacon 2021-01-20 17:36 ` Will Deacon 2021-01-20 18:27 ` Nick Desaulniers 2021-01-20 18:27 ` Nick Desaulniers 2021-01-20 18:27 ` Nick Desaulniers 2021-01-20 19:02 ` Linus Torvalds 2021-01-20 19:02 ` Linus Torvalds 2021-01-20 19:02 ` Linus Torvalds 2021-01-21 13:11 ` Will Deacon 2021-01-21 13:11 ` Will Deacon 2021-01-21 19:24 ` Nick Desaulniers 2021-01-21 19:24 ` Nick Desaulniers 2021-01-21 19:24 ` Nick Desaulniers 2021-01-21 21:28 ` Will Deacon 2021-01-21 21:28 ` Will Deacon 2021-01-22 19:10 ` Nick Desaulniers 2021-01-22 19:10 ` Nick Desaulniers 2021-01-22 19:10 ` Nick Desaulniers 2021-01-22 19:27 ` Will Deacon 2021-01-22 19:27 ` Will Deacon 2021-01-22 17:47 ` Linus Torvalds 2021-01-22 17:47 ` Linus Torvalds 2021-01-22 17:47 ` Linus Torvalds 2021-01-26 23:08 ` [PATCH v4 0/8] Create 'old' ptes for faultaround mappings on arm64 with hardware access flag Will Deacon 2021-01-26 23:08 ` Will Deacon 2021-01-26 23:28 ` Hugh Dickins 2021-01-26 23:28 ` Hugh Dickins 2021-01-26 23:28 ` Hugh Dickins 2021-01-27 17:16 ` Will Deacon 2021-01-27 17:16 ` Will Deacon
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20210120173612.20913-7-will@kernel.org \ --to=will@kernel.org \ --cc=akpm@linux-foundation.org \ --cc=catalin.marinas@arm.com \ --cc=hughd@google.com \ --cc=jack@suse.cz \ --cc=kernel-team@android.com \ --cc=kirill.shutemov@linux.intel.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=minchan@kernel.org \ --cc=ndesaulniers@google.com \ --cc=torvalds@linux-foundation.org \ --cc=vinmenon@codeaurora.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.