Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752504AbbBWQVi (ORCPT ); Mon, 23 Feb 2015 11:21:38 -0500 Received: from cantor2.suse.de ([195.135.220.15]:44298 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751618AbbBWQVh (ORCPT ); Mon, 23 Feb 2015 11:21:37 -0500 Message-ID: <54EB538B.7040308@suse.cz> Date: Mon, 23 Feb 2015 17:21:31 +0100 From: Vlastimil Babka User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: "Kirill A. Shutemov" , Andrew Morton , Andrea Arcangeli , Hugh Dickins CC: Dave Hansen , Mel Gorman , Rik van Riel , Christoph Lameter , Naoya Horiguchi , Steve Capper , "Aneesh Kumar K.V" , Johannes Weiner , Michal Hocko , Jerome Marchand , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCHv3 04/24] rmap: add argument to charge compound page References: <1423757918-197669-1-git-send-email-kirill.shutemov@linux.intel.com> <1423757918-197669-5-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1423757918-197669-5-git-send-email-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=iso-8859-2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17381 Lines: 462 On 02/12/2015 05:18 PM, Kirill A. Shutemov wrote: > We're going to allow mapping of individual 4k pages of THP compound > page. It means we cannot rely on PageTransHuge() check to decide if map > small page or THP. > > The patch adds new argument to rmap function to indicate whethe we want > to map whole compound page or only the small page. > > Signed-off-by: Kirill A. Shutemov > --- > include/linux/rmap.h | 14 +++++++++++--- > kernel/events/uprobes.c | 4 ++-- > mm/huge_memory.c | 16 ++++++++-------- > mm/hugetlb.c | 4 ++-- > mm/ksm.c | 4 ++-- > mm/memory.c | 14 +++++++------- > mm/migrate.c | 8 ++++---- > mm/rmap.c | 43 +++++++++++++++++++++++++++---------------- > mm/swapfile.c | 4 ++-- > 9 files changed, 65 insertions(+), 46 deletions(-) > > diff --git a/include/linux/rmap.h b/include/linux/rmap.h > index c4088feac1fc..3bf73620b672 100644 > --- a/include/linux/rmap.h > +++ b/include/linux/rmap.h > @@ -168,16 +168,24 @@ static inline void anon_vma_merge(struct vm_area_struct *vma, > > struct anon_vma *page_get_anon_vma(struct page *page); > > +/* flags for do_page_add_anon_rmap() */ > +enum { > + RMAP_EXCLUSIVE = 1, > + RMAP_COMPOUND = 2, > +}; > + > /* > * rmap interfaces called when adding or removing pte of page > */ > void page_move_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); > -void page_add_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); > +void page_add_anon_rmap(struct page *, struct vm_area_struct *, > + unsigned long, bool); > void do_page_add_anon_rmap(struct page *, struct vm_area_struct *, > unsigned long, int); > -void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); > +void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, > + unsigned long, bool); > void page_add_file_rmap(struct page *); > -void page_remove_rmap(struct page *); > +void page_remove_rmap(struct page *, bool); > > void hugepage_add_anon_rmap(struct page *, struct vm_area_struct *, > unsigned long); > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c > index cb346f26a22d..5523daf59953 100644 > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -183,7 +183,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, > goto unlock; > > get_page(kpage); > - page_add_new_anon_rmap(kpage, vma, addr); > + page_add_new_anon_rmap(kpage, vma, addr, false); > mem_cgroup_commit_charge(kpage, memcg, false); > lru_cache_add_active_or_unevictable(kpage, vma); > > @@ -196,7 +196,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, > ptep_clear_flush_notify(vma, addr, ptep); > set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot)); > > - page_remove_rmap(page); > + page_remove_rmap(page, false); > if (!page_mapped(page)) > try_to_free_swap(page); > pte_unmap_unlock(ptep, ptl); > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 5f4c97e1a6da..36637a80669e 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -743,7 +743,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm, > pmd_t entry; > entry = mk_huge_pmd(page, vma->vm_page_prot); > entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); > - page_add_new_anon_rmap(page, vma, haddr); > + page_add_new_anon_rmap(page, vma, haddr, true); > mem_cgroup_commit_charge(page, memcg, false); > lru_cache_add_active_or_unevictable(page, vma); > pgtable_trans_huge_deposit(mm, pmd, pgtable); > @@ -1034,7 +1034,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, > entry = maybe_mkwrite(pte_mkdirty(entry), vma); > memcg = (void *)page_private(pages[i]); > set_page_private(pages[i], 0); > - page_add_new_anon_rmap(pages[i], vma, haddr); > + page_add_new_anon_rmap(pages[i], vma, haddr, false); > mem_cgroup_commit_charge(pages[i], memcg, false); > lru_cache_add_active_or_unevictable(pages[i], vma); > pte = pte_offset_map(&_pmd, haddr); > @@ -1046,7 +1046,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, > > smp_wmb(); /* make pte visible before pmd */ > pmd_populate(mm, pmd, pgtable); > - page_remove_rmap(page); > + page_remove_rmap(page, true); > spin_unlock(ptl); > > mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); > @@ -1168,7 +1168,7 @@ alloc: > entry = mk_huge_pmd(new_page, vma->vm_page_prot); > entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); > pmdp_clear_flush_notify(vma, haddr, pmd); > - page_add_new_anon_rmap(new_page, vma, haddr); > + page_add_new_anon_rmap(new_page, vma, haddr, true); > mem_cgroup_commit_charge(new_page, memcg, false); > lru_cache_add_active_or_unevictable(new_page, vma); > set_pmd_at(mm, haddr, pmd, entry); > @@ -1178,7 +1178,7 @@ alloc: > put_huge_zero_page(); > } else { > VM_BUG_ON_PAGE(!PageHead(page), page); > - page_remove_rmap(page); > + page_remove_rmap(page, true); > put_page(page); > } > ret |= VM_FAULT_WRITE; > @@ -1431,7 +1431,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, > put_huge_zero_page(); > } else { > page = pmd_page(orig_pmd); > - page_remove_rmap(page); > + page_remove_rmap(page, true); > VM_BUG_ON_PAGE(page_mapcount(page) < 0, page); > add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR); > VM_BUG_ON_PAGE(!PageHead(page), page); > @@ -2368,7 +2368,7 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page, > * superfluous. > */ > pte_clear(vma->vm_mm, address, _pte); > - page_remove_rmap(src_page); > + page_remove_rmap(src_page, false); > spin_unlock(ptl); > free_page_and_swap_cache(src_page); > } > @@ -2658,7 +2658,7 @@ static void collapse_huge_page(struct mm_struct *mm, > > spin_lock(pmd_ptl); > BUG_ON(!pmd_none(*pmd)); > - page_add_new_anon_rmap(new_page, vma, address); > + page_add_new_anon_rmap(new_page, vma, address, true); > mem_cgroup_commit_charge(new_page, memcg, false); > lru_cache_add_active_or_unevictable(new_page, vma); > pgtable_trans_huge_deposit(mm, pmd, pgtable); > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 0a9ac6c26832..ebb7329301c4 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -2688,7 +2688,7 @@ again: > if (huge_pte_dirty(pte)) > set_page_dirty(page); > > - page_remove_rmap(page); > + page_remove_rmap(page, true); > force_flush = !__tlb_remove_page(tlb, page); > if (force_flush) { > address += sz; > @@ -2908,7 +2908,7 @@ retry_avoidcopy: > mmu_notifier_invalidate_range(mm, mmun_start, mmun_end); > set_huge_pte_at(mm, address, ptep, > make_huge_pte(vma, new_page, 1)); > - page_remove_rmap(old_page); > + page_remove_rmap(old_page, true); > hugepage_add_new_anon_rmap(new_page, vma, address); > /* Make the old page be freed below */ > new_page = old_page; > diff --git a/mm/ksm.c b/mm/ksm.c > index 4162dce2eb44..92182eeba87d 100644 > --- a/mm/ksm.c > +++ b/mm/ksm.c > @@ -957,13 +957,13 @@ static int replace_page(struct vm_area_struct *vma, struct page *page, > } > > get_page(kpage); > - page_add_anon_rmap(kpage, vma, addr); > + page_add_anon_rmap(kpage, vma, addr, false); > > flush_cache_page(vma, addr, pte_pfn(*ptep)); > ptep_clear_flush_notify(vma, addr, ptep); > set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot)); > > - page_remove_rmap(page); > + page_remove_rmap(page, false); > if (!page_mapped(page)) > try_to_free_swap(page); > put_page(page); > diff --git a/mm/memory.c b/mm/memory.c > index 8ae52c918415..5529627d2cd6 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -1125,7 +1125,7 @@ again: > mark_page_accessed(page); > rss[MM_FILEPAGES]--; > } > - page_remove_rmap(page); > + page_remove_rmap(page, false); > if (unlikely(page_mapcount(page) < 0)) > print_bad_pte(vma, addr, ptent, page); > if (unlikely(!__tlb_remove_page(tlb, page))) { > @@ -2189,7 +2189,7 @@ gotten: > * thread doing COW. > */ > ptep_clear_flush_notify(vma, address, page_table); > - page_add_new_anon_rmap(new_page, vma, address); > + page_add_new_anon_rmap(new_page, vma, address, false); > mem_cgroup_commit_charge(new_page, memcg, false); > lru_cache_add_active_or_unevictable(new_page, vma); > /* > @@ -2222,7 +2222,7 @@ gotten: > * mapcount is visible. So transitively, TLBs to > * old page will be flushed before it can be reused. > */ > - page_remove_rmap(old_page); > + page_remove_rmap(old_page, false); > } > > /* Free the old page.. */ > @@ -2465,7 +2465,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, > pte = maybe_mkwrite(pte_mkdirty(pte), vma); > flags &= ~FAULT_FLAG_WRITE; > ret |= VM_FAULT_WRITE; > - exclusive = 1; > + exclusive = RMAP_EXCLUSIVE; > } > flush_icache_page(vma, page); > if (pte_swp_soft_dirty(orig_pte)) > @@ -2475,7 +2475,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, > do_page_add_anon_rmap(page, vma, address, exclusive); > mem_cgroup_commit_charge(page, memcg, true); > } else { /* ksm created a completely new copy */ > - page_add_new_anon_rmap(page, vma, address); > + page_add_new_anon_rmap(page, vma, address, false); > mem_cgroup_commit_charge(page, memcg, false); > lru_cache_add_active_or_unevictable(page, vma); > } > @@ -2613,7 +2613,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, > goto release; > > inc_mm_counter_fast(mm, MM_ANONPAGES); > - page_add_new_anon_rmap(page, vma, address); > + page_add_new_anon_rmap(page, vma, address, false); > mem_cgroup_commit_charge(page, memcg, false); > lru_cache_add_active_or_unevictable(page, vma); > setpte: > @@ -2701,7 +2701,7 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address, > entry = maybe_mkwrite(pte_mkdirty(entry), vma); > if (anon) { > inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); > - page_add_new_anon_rmap(page, vma, address); > + page_add_new_anon_rmap(page, vma, address, false); > } else { > inc_mm_counter_fast(vma->vm_mm, MM_FILEPAGES); > page_add_file_rmap(page); > diff --git a/mm/migrate.c b/mm/migrate.c > index 85e042686031..0d2b3110277a 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -166,7 +166,7 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma, > else > page_dup_rmap(new); > } else if (PageAnon(new)) > - page_add_anon_rmap(new, vma, addr); > + page_add_anon_rmap(new, vma, addr, false); > else > page_add_file_rmap(new); > > @@ -1803,7 +1803,7 @@ fail_putback: > * guarantee the copy is visible before the pagetable update. > */ > flush_cache_range(vma, mmun_start, mmun_end); > - page_add_anon_rmap(new_page, vma, mmun_start); > + page_add_anon_rmap(new_page, vma, mmun_start, true); > pmdp_clear_flush_notify(vma, mmun_start, pmd); > set_pmd_at(mm, mmun_start, pmd, entry); > flush_tlb_range(vma, mmun_start, mmun_end); > @@ -1814,13 +1814,13 @@ fail_putback: > flush_tlb_range(vma, mmun_start, mmun_end); > mmu_notifier_invalidate_range(mm, mmun_start, mmun_end); > update_mmu_cache_pmd(vma, address, &entry); > - page_remove_rmap(new_page); > + page_remove_rmap(new_page, true); > goto fail_putback; > } > > mem_cgroup_migrate(page, new_page, false); > > - page_remove_rmap(page); > + page_remove_rmap(page, true); > > spin_unlock(ptl); > mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); > diff --git a/mm/rmap.c b/mm/rmap.c > index 47b3ba87c2dd..f67e83be75e4 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -1041,9 +1041,9 @@ static void __page_check_anon_rmap(struct page *page, > * (but PageKsm is never downgraded to PageAnon). > */ > void page_add_anon_rmap(struct page *page, > - struct vm_area_struct *vma, unsigned long address) > + struct vm_area_struct *vma, unsigned long address, bool compound) > { > - do_page_add_anon_rmap(page, vma, address, 0); > + do_page_add_anon_rmap(page, vma, address, compound ? RMAP_COMPOUND : 0); > } > > /* > @@ -1052,21 +1052,24 @@ void page_add_anon_rmap(struct page *page, > * Everybody else should continue to use page_add_anon_rmap above. > */ > void do_page_add_anon_rmap(struct page *page, > - struct vm_area_struct *vma, unsigned long address, int exclusive) > + struct vm_area_struct *vma, unsigned long address, int flags) > { > int first = atomic_inc_and_test(&page->_mapcount); > if (first) { > + bool compound = flags & RMAP_COMPOUND; > + int nr = compound ? hpage_nr_pages(page) : 1; hpage_nr_pages(page) is: static inline int hpage_nr_pages(struct page *page) { if (unlikely(PageTransHuge(page))) return HPAGE_PMD_NR; return 1; } and later... > /* > * We use the irq-unsafe __{inc|mod}_zone_page_stat because > * these counters are not modified in interrupt context, and > * pte lock(a spinlock) is held, which implies preemption > * disabled. > */ > - if (PageTransHuge(page)) > + if (compound) { > + VM_BUG_ON_PAGE(!PageTransHuge(page), page); this means that we could assume that (compound == true) => (PageTransHuge(page) == true) and simplify above to: int nr = compound ? HPAGE_PMD_NR : 1; Right? Same thing seems to hold for the two other variants below. > __inc_zone_page_state(page, > NR_ANON_TRANSPARENT_HUGEPAGES); > - __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, > - hpage_nr_pages(page)); > + } > + __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, nr); > } > if (unlikely(PageKsm(page))) > return; > @@ -1074,7 +1077,8 @@ void do_page_add_anon_rmap(struct page *page, > VM_BUG_ON_PAGE(!PageLocked(page), page); > /* address might be in next vma when migration races vma_adjust */ > if (first) > - __page_set_anon_rmap(page, vma, address, exclusive); > + __page_set_anon_rmap(page, vma, address, > + flags & RMAP_EXCLUSIVE); > else > __page_check_anon_rmap(page, vma, address); > } > @@ -1090,15 +1094,18 @@ void do_page_add_anon_rmap(struct page *page, > * Page does not have to be locked. > */ > void page_add_new_anon_rmap(struct page *page, > - struct vm_area_struct *vma, unsigned long address) > + struct vm_area_struct *vma, unsigned long address, bool compound) > { > + int nr = compound ? hpage_nr_pages(page) : 1; > + > VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); > SetPageSwapBacked(page); > atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */ > - if (PageTransHuge(page)) > + if (compound) { > + VM_BUG_ON_PAGE(!PageTransHuge(page), page); > __inc_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); > - __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, > - hpage_nr_pages(page)); > + } > + __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, nr); > __page_set_anon_rmap(page, vma, address, 1); > } > > @@ -1154,9 +1161,12 @@ out: > * > * The caller needs to hold the pte lock. > */ > -void page_remove_rmap(struct page *page) > +void page_remove_rmap(struct page *page, bool compound) > { > + int nr = compound ? hpage_nr_pages(page) : 1; > + > if (!PageAnon(page)) { > + VM_BUG_ON_PAGE(compound && !PageHuge(page), page); > page_remove_file_rmap(page); > return; > } > @@ -1174,11 +1184,12 @@ void page_remove_rmap(struct page *page) > * these counters are not modified in interrupt context, and > * pte lock(a spinlock) is held, which implies preemption disabled. > */ > - if (PageTransHuge(page)) > + if (compound) { > + VM_BUG_ON_PAGE(!PageTransHuge(page), page); > __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); > + } > > - __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, > - -hpage_nr_pages(page)); > + __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, -nr); > > if (unlikely(PageMlocked(page))) > clear_page_mlock(page); > @@ -1320,7 +1331,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, > dec_mm_counter(mm, MM_FILEPAGES); > > discard: > - page_remove_rmap(page); > + page_remove_rmap(page, false); > page_cache_release(page); > > out_unmap: > diff --git a/mm/swapfile.c b/mm/swapfile.c > index 63f55ccb9b26..200298895cee 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -1121,10 +1121,10 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, > set_pte_at(vma->vm_mm, addr, pte, > pte_mkold(mk_pte(page, vma->vm_page_prot))); > if (page == swapcache) { > - page_add_anon_rmap(page, vma, addr); > + page_add_anon_rmap(page, vma, addr, false); > mem_cgroup_commit_charge(page, memcg, true); > } else { /* ksm created a completely new copy */ > - page_add_new_anon_rmap(page, vma, addr); > + page_add_new_anon_rmap(page, vma, addr, false); > mem_cgroup_commit_charge(page, memcg, false); > lru_cache_add_active_or_unevictable(page, vma); > } > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/