* [PATCH 0/2] Reverts to address unixbench regression @ 2016-06-14 8:42 Kirill A. Shutemov 2016-06-14 8:42 ` [PATCH 1/2] Revert "mm: make faultaround produce old ptes" Kirill A. Shutemov 2016-06-14 8:42 ` [PATCH 2/2] Revert "mm: disable fault around on emulated access bit architecture" Kirill A. Shutemov 0 siblings, 2 replies; 6+ messages in thread From: Kirill A. Shutemov @ 2016-06-14 8:42 UTC (permalink / raw) To: Linus Torvalds, Andrew Morton Cc: Rik van Riel, Mel Gorman, Huang, Ying, Michal Hocko, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm, Kirill A. Shutemov Faultaround changes cause regression in unixbench, let's revert them. Kirill A. Shutemov (2): Revert "mm: make faultaround produce old ptes" Revert "mm: disable fault around on emulated access bit architecture" include/linux/mm.h | 2 +- mm/filemap.c | 2 +- mm/memory.c | 31 +++++-------------------------- 3 files changed, 7 insertions(+), 28 deletions(-) -- 2.8.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] Revert "mm: make faultaround produce old ptes" 2016-06-14 8:42 [PATCH 0/2] Reverts to address unixbench regression Kirill A. Shutemov @ 2016-06-14 8:42 ` Kirill A. Shutemov 2016-06-16 12:20 ` Michal Hocko 2016-06-14 8:42 ` [PATCH 2/2] Revert "mm: disable fault around on emulated access bit architecture" Kirill A. Shutemov 1 sibling, 1 reply; 6+ messages in thread From: Kirill A. Shutemov @ 2016-06-14 8:42 UTC (permalink / raw) To: Linus Torvalds, Andrew Morton Cc: Rik van Riel, Mel Gorman, Huang, Ying, Michal Hocko, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm, Kirill A. Shutemov 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. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: "Huang, Ying" <ying.huang@intel.com> --- include/linux/mm.h | 2 +- mm/filemap.c | 2 +- mm/memory.c | 23 +++++------------------ 3 files changed, 7 insertions(+), 20 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5df5feb49575..ece042dfe23c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -602,7 +602,7 @@ static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) } 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); #endif /* diff --git a/mm/filemap.c b/mm/filemap.c index 00ae878b2a38..20f3b1f33f0e 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2186,7 +2186,7 @@ repeat: if (file->f_ra.mmap_miss > 0) file->f_ra.mmap_miss--; addr = address + (page->index - vmf->pgoff) * PAGE_SIZE; - do_set_pte(vma, addr, page, pte, false, false, true); + do_set_pte(vma, addr, page, pte, false, false); unlock_page(page); goto next; unlock: 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)) -- 2.8.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] Revert "mm: make faultaround produce old ptes" 2016-06-14 8:42 ` [PATCH 1/2] Revert "mm: make faultaround produce old ptes" Kirill A. Shutemov @ 2016-06-16 12:20 ` Michal Hocko 2016-06-16 12:27 ` Kirill A. Shutemov 0 siblings, 1 reply; 6+ messages in thread From: Michal Hocko @ 2016-06-16 12:20 UTC (permalink / raw) To: Kirill A. Shutemov Cc: Linus Torvalds, Andrew Morton, Rik van Riel, Mel Gorman, Huang, Ying, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm On Tue 14-06-16 11:42:29, Kirill A. Shutemov wrote: > This reverts commit 5c0a85fad949212b3e059692deecdeed74ae7ec7. > > The commit causes ~6% regression in unixbench. Is the regression fully explained? My understanding from the email thread is that this is suspiciously too high. It is not like I would be against the revert but having an explanation would be really appreciated. > Let's revert it for now and consider other solution for reclaim problem > later. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > Reported-by: "Huang, Ying" <ying.huang@intel.com> > --- > include/linux/mm.h | 2 +- > mm/filemap.c | 2 +- > mm/memory.c | 23 +++++------------------ > 3 files changed, 7 insertions(+), 20 deletions(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 5df5feb49575..ece042dfe23c 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -602,7 +602,7 @@ static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) > } > > 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); > #endif > > /* > diff --git a/mm/filemap.c b/mm/filemap.c > index 00ae878b2a38..20f3b1f33f0e 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -2186,7 +2186,7 @@ repeat: > if (file->f_ra.mmap_miss > 0) > file->f_ra.mmap_miss--; > addr = address + (page->index - vmf->pgoff) * PAGE_SIZE; > - do_set_pte(vma, addr, page, pte, false, false, true); > + do_set_pte(vma, addr, page, pte, false, false); > unlock_page(page); > goto next; > unlock: > 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)) > -- > 2.8.1 > -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] Revert "mm: make faultaround produce old ptes" 2016-06-16 12:20 ` Michal Hocko @ 2016-06-16 12:27 ` Kirill A. Shutemov 2016-06-16 15:10 ` Michal Hocko 0 siblings, 1 reply; 6+ messages in thread From: Kirill A. Shutemov @ 2016-06-16 12:27 UTC (permalink / raw) To: Michal Hocko Cc: Linus Torvalds, Andrew Morton, Rik van Riel, Mel Gorman, Huang, Ying, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm On Thu, Jun 16, 2016 at 02:20:02PM +0200, Michal Hocko wrote: > On Tue 14-06-16 11:42:29, Kirill A. Shutemov wrote: > > This reverts commit 5c0a85fad949212b3e059692deecdeed74ae7ec7. > > > > The commit causes ~6% regression in unixbench. > > Is the regression fully explained? My understanding from the email > thread is that this is suspiciously too high. It is not like I would > be against the revert but having an explanation would be really > appreciated. My understanding is that it's overhead on setting accessed bit: http://lkml.kernel.org/r/20160613125248.GA30109@black.fi.intel.com -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] Revert "mm: make faultaround produce old ptes" 2016-06-16 12:27 ` Kirill A. Shutemov @ 2016-06-16 15:10 ` Michal Hocko 0 siblings, 0 replies; 6+ messages in thread From: Michal Hocko @ 2016-06-16 15:10 UTC (permalink / raw) To: Kirill A. Shutemov Cc: Linus Torvalds, Andrew Morton, Rik van Riel, Mel Gorman, Huang, Ying, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm On Thu 16-06-16 15:27:35, Kirill A. Shutemov wrote: > On Thu, Jun 16, 2016 at 02:20:02PM +0200, Michal Hocko wrote: > > On Tue 14-06-16 11:42:29, Kirill A. Shutemov wrote: > > > This reverts commit 5c0a85fad949212b3e059692deecdeed74ae7ec7. > > > > > > The commit causes ~6% regression in unixbench. > > > > Is the regression fully explained? My understanding from the email > > thread is that this is suspiciously too high. It is not like I would > > be against the revert but having an explanation would be really > > appreciated. > > My understanding is that it's overhead on setting accessed bit: > > http://lkml.kernel.org/r/20160613125248.GA30109@black.fi.intel.com But those numbers cannot explain the regression completely AFAIU. It smells like something else is going on. Anyway, as I've said I do not have anything against the revert just more than "unixbench regresses" would be nice. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/2] Revert "mm: disable fault around on emulated access bit architecture" 2016-06-14 8:42 [PATCH 0/2] Reverts to address unixbench regression Kirill A. Shutemov 2016-06-14 8:42 ` [PATCH 1/2] Revert "mm: make faultaround produce old ptes" Kirill A. Shutemov @ 2016-06-14 8:42 ` Kirill A. Shutemov 1 sibling, 0 replies; 6+ messages in thread From: Kirill A. Shutemov @ 2016-06-14 8:42 UTC (permalink / raw) To: Linus Torvalds, Andrew Morton Cc: Rik van Riel, Mel Gorman, Huang, Ying, Michal Hocko, Minchan Kim, Vinayak Menon, Dave Hansen, linux-kernel, linux-mm, Kirill A. Shutemov 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. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> --- mm/memory.c | 8 -------- 1 file changed, 8 deletions(-) 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) -- 2.8.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2016-06-16 15:10 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2016-06-14 8:42 [PATCH 0/2] Reverts to address unixbench regression Kirill A. Shutemov 2016-06-14 8:42 ` [PATCH 1/2] Revert "mm: make faultaround produce old ptes" Kirill A. Shutemov 2016-06-16 12:20 ` Michal Hocko 2016-06-16 12:27 ` Kirill A. Shutemov 2016-06-16 15:10 ` Michal Hocko 2016-06-14 8:42 ` [PATCH 2/2] Revert "mm: disable fault around on emulated access bit architecture" Kirill A. Shutemov
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