From 315d09bf30c2b436a1fdac86d31c24380cd56c4f Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 24 Jun 2016 14:49:45 -0700 Subject: Revert "mm: make faultaround produce old ptes" This reverts commit 5c0a85fad949212b3e059692deecdeed74ae7ec7. The commit causes ~6% regression in unixbench. Let's revert it for now and consider other solution for reclaim problem later. Link: http://lkml.kernel.org/r/1465893750-44080-2-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Reported-by: "Huang, Ying" Cc: Linus Torvalds Cc: Rik van Riel Cc: Mel Gorman Cc: Michal Hocko Cc: Minchan Kim Cc: Vinayak Menon Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 23 +++++------------------ 1 file changed, 5 insertions(+), 18 deletions(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 15322b73636b..61fe7e7b56bf 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2877,7 +2877,7 @@ static int __do_fault(struct vm_area_struct *vma, unsigned long address, * vm_ops->map_pages. */ void do_set_pte(struct vm_area_struct *vma, unsigned long address, - struct page *page, pte_t *pte, bool write, bool anon, bool old) + struct page *page, pte_t *pte, bool write, bool anon) { pte_t entry; @@ -2885,8 +2885,6 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address, entry = mk_pte(page, vma->vm_page_prot); if (write) entry = maybe_mkwrite(pte_mkdirty(entry), vma); - if (old) - entry = pte_mkold(entry); if (anon) { inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); page_add_new_anon_rmap(page, vma, address, false); @@ -3032,20 +3030,9 @@ static int do_read_fault(struct mm_struct *mm, struct vm_area_struct *vma, */ if (vma->vm_ops->map_pages && fault_around_bytes >> PAGE_SHIFT > 1) { pte = pte_offset_map_lock(mm, pmd, address, &ptl); - if (!pte_same(*pte, orig_pte)) - goto unlock_out; do_fault_around(vma, address, pte, pgoff, flags); - /* Check if the fault is handled by faultaround */ - if (!pte_same(*pte, orig_pte)) { - /* - * Faultaround produce old pte, but the pte we've - * handler fault for should be young. - */ - pte_t entry = pte_mkyoung(*pte); - if (ptep_set_access_flags(vma, address, pte, entry, 0)) - update_mmu_cache(vma, address, pte); + if (!pte_same(*pte, orig_pte)) goto unlock_out; - } pte_unmap_unlock(pte, ptl); } @@ -3060,7 +3047,7 @@ static int do_read_fault(struct mm_struct *mm, struct vm_area_struct *vma, put_page(fault_page); return ret; } - do_set_pte(vma, address, fault_page, pte, false, false, false); + do_set_pte(vma, address, fault_page, pte, false, false); unlock_page(fault_page); unlock_out: pte_unmap_unlock(pte, ptl); @@ -3111,7 +3098,7 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma, } goto uncharge_out; } - do_set_pte(vma, address, new_page, pte, true, true, false); + do_set_pte(vma, address, new_page, pte, true, true); mem_cgroup_commit_charge(new_page, memcg, false, false); lru_cache_add_active_or_unevictable(new_page, vma); pte_unmap_unlock(pte, ptl); @@ -3164,7 +3151,7 @@ static int do_shared_fault(struct mm_struct *mm, struct vm_area_struct *vma, put_page(fault_page); return ret; } - do_set_pte(vma, address, fault_page, pte, true, false, false); + do_set_pte(vma, address, fault_page, pte, true, false); pte_unmap_unlock(pte, ptl); if (set_page_dirty(fault_page)) -- cgit v1.2.3 From 06d8fbc7cfd655d202cfac9870bd79c18c2db698 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 24 Jun 2016 14:49:48 -0700 Subject: Revert "mm: disable fault around on emulated access bit architecture" This reverts commit d0834a6c2c5b0c76cfb806bd7dba6556d8b4edbb. After revert of 5c0a85fad949 ("mm: make faultaround produce old ptes") faultaround doesn't have dependencies on hardware accessed bit, so let's revert this one too. Link: http://lkml.kernel.org/r/1465893750-44080-3-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Reported-by: "Huang, Ying" Cc: Linus Torvalds Cc: Rik van Riel Cc: Mel Gorman Cc: Michal Hocko Cc: Minchan Kim Cc: Vinayak Menon Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 61fe7e7b56bf..cd1f29e4897e 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2898,16 +2898,8 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address, update_mmu_cache(vma, address, pte); } -/* - * If architecture emulates "accessed" or "young" bit without HW support, - * there is no much gain with fault_around. - */ static unsigned long fault_around_bytes __read_mostly = -#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS - PAGE_SIZE; -#else rounddown_pow_of_two(65536); -#endif #ifdef CONFIG_DEBUG_FS static int fault_around_bytes_get(void *data, u64 *val) -- cgit v1.2.3