From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f197.google.com (mail-pg1-f197.google.com [209.85.215.197]) by kanga.kvack.org (Postfix) with ESMTP id 77E4C6B0266 for ; Tue, 16 Oct 2018 09:14:22 -0400 (EDT) Received: by mail-pg1-f197.google.com with SMTP id r134-v6so12031819pgr.19 for ; Tue, 16 Oct 2018 06:14:22 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id l20-v6sor4443475pgh.86.2018.10.16.06.14.21 for (Google Transport Security); Tue, 16 Oct 2018 06:14:21 -0700 (PDT) From: Nicholas Piggin Subject: [PATCH v2 5/5] mm: optimise pte dirty/accessed bit setting by demand based pte insertion Date: Tue, 16 Oct 2018 23:13:43 +1000 Message-Id: <20181016131343.20556-6-npiggin@gmail.com> In-Reply-To: <20181016131343.20556-1-npiggin@gmail.com> References: <20181016131343.20556-1-npiggin@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Nicholas Piggin , Linus Torvalds , linux-mm , linux-arch , Linux Kernel Mailing List , ppc-dev , Ley Foon Tan Similarly to the previous patch, this tries to optimise dirty/accessed bits in ptes to avoid access costs of hardware setting them. Signed-off-by: Nicholas Piggin --- mm/huge_memory.c | 12 ++++++++---- mm/memory.c | 9 ++++++--- 2 files changed, 14 insertions(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1f43265204d4..38c2cd3b4879 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1197,6 +1197,7 @@ static vm_fault_t do_huge_pmd_wp_page_fallback(struct vm_fault *vmf, for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { pte_t entry; entry = mk_pte(pages[i], vma->vm_page_prot); + entry = pte_mkyoung(entry); entry = maybe_mkwrite(pte_mkdirty(entry), vma); memcg = (void *)page_private(pages[i]); set_page_private(pages[i], 0); @@ -2067,7 +2068,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, struct page *page; pgtable_t pgtable; pmd_t old_pmd, _pmd; - bool young, write, soft_dirty, pmd_migration = false; + bool young, write, dirty, soft_dirty, pmd_migration = false; unsigned long addr; int i; @@ -2145,7 +2146,8 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, page = pmd_page(old_pmd); VM_BUG_ON_PAGE(!page_count(page), page); page_ref_add(page, HPAGE_PMD_NR - 1); - if (pmd_dirty(old_pmd)) + dirty = pmd_dirty(old_pmd); + if (dirty) SetPageDirty(page); write = pmd_write(old_pmd); young = pmd_young(old_pmd); @@ -2176,8 +2178,10 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = maybe_mkwrite(entry, vma); if (!write) entry = pte_wrprotect(entry); - if (!young) - entry = pte_mkold(entry); + if (young) + entry = pte_mkyoung(entry); + if (dirty) + entry = pte_mkdirty(entry); if (soft_dirty) entry = pte_mksoft_dirty(entry); } diff --git a/mm/memory.c b/mm/memory.c index 9e314339a0bd..f907ea7a6303 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1804,10 +1804,9 @@ static int insert_pfn(struct vm_area_struct *vma, unsigned long addr, entry = pte_mkspecial(pfn_t_pte(pfn, prot)); out_mkwrite: - if (mkwrite) { - entry = pte_mkyoung(entry); + entry = pte_mkyoung(entry); + if (mkwrite) entry = maybe_mkwrite(pte_mkdirty(entry), vma); - } set_pte_at(mm, addr, pte, entry); update_mmu_cache(vma, addr, pte); /* XXX: why not for insert_page? */ @@ -2534,6 +2533,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) } flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte)); entry = mk_pte(new_page, vma->vm_page_prot); + entry = pte_mkyoung(entry); entry = maybe_mkwrite(pte_mkdirty(entry), vma); /* * Clear the pte entry and flush it first, before updating the @@ -3043,6 +3043,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); dec_mm_counter_fast(vma->vm_mm, MM_SWAPENTS); pte = mk_pte(page, vma->vm_page_prot); + pte = pte_mkyoung(pte); if ((vmf->flags & FAULT_FLAG_WRITE) && reuse_swap_page(page, NULL)) { pte = maybe_mkwrite(pte_mkdirty(pte), vma); vmf->flags &= ~FAULT_FLAG_WRITE; @@ -3185,6 +3186,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) __SetPageUptodate(page); entry = mk_pte(page, vma->vm_page_prot); + entry = pte_mkyoung(entry); if (vma->vm_flags & VM_WRITE) entry = pte_mkwrite(pte_mkdirty(entry)); @@ -3453,6 +3455,7 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg, flush_icache_page(vma, page); entry = mk_pte(page, vma->vm_page_prot); + entry = pte_mkyoung(entry); if (write) entry = maybe_mkwrite(pte_mkdirty(entry), vma); /* copy-on-write page */ -- 2.18.0