diff options
Diffstat (limited to 'mm/huge_memory.c')
-rw-r--r-- | mm/huge_memory.c | 146 |
1 files changed, 113 insertions, 33 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index e60837dc785..d9a21d06b86 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -715,13 +715,20 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm, unsigned long haddr, pmd_t *pmd, struct page *page) { + struct mem_cgroup *memcg; pgtable_t pgtable; spinlock_t *ptl; VM_BUG_ON_PAGE(!PageCompound(page), page); + + if (mem_cgroup_try_charge(page, mm, GFP_TRANSHUGE, &memcg)) + return VM_FAULT_OOM; + pgtable = pte_alloc_one(mm, haddr); - if (unlikely(!pgtable)) + if (unlikely(!pgtable)) { + mem_cgroup_cancel_charge(page, memcg); return VM_FAULT_OOM; + } clear_huge_page(page, haddr, HPAGE_PMD_NR); /* @@ -734,7 +741,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm, ptl = pmd_lock(mm, pmd); if (unlikely(!pmd_none(*pmd))) { spin_unlock(ptl); - mem_cgroup_uncharge_page(page); + mem_cgroup_cancel_charge(page, memcg); put_page(page); pte_free(mm, pgtable); } else { @@ -742,6 +749,8 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm, 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); + mem_cgroup_commit_charge(page, memcg, false); + lru_cache_add_active_or_unevictable(page, vma); pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, haddr, pmd, entry); add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR); @@ -827,13 +836,7 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, count_vm_event(THP_FAULT_FALLBACK); return VM_FAULT_FALLBACK; } - if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_KERNEL))) { - put_page(page); - count_vm_event(THP_FAULT_FALLBACK); - return VM_FAULT_FALLBACK; - } if (unlikely(__do_huge_pmd_anonymous_page(mm, vma, haddr, pmd, page))) { - mem_cgroup_uncharge_page(page); put_page(page); count_vm_event(THP_FAULT_FALLBACK); return VM_FAULT_FALLBACK; @@ -941,6 +944,37 @@ unlock: spin_unlock(ptl); } +/* + * Save CONFIG_DEBUG_PAGEALLOC from faulting falsely on tail pages + * during copy_user_huge_page()'s copy_page_rep(): in the case when + * the source page gets split and a tail freed before copy completes. + * Called under pmd_lock of checked pmd, so safe from splitting itself. + */ +static void get_user_huge_page(struct page *page) +{ + if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) { + struct page *endpage = page + HPAGE_PMD_NR; + + atomic_add(HPAGE_PMD_NR, &page->_count); + while (++page < endpage) + get_huge_page_tail(page); + } else { + get_page(page); + } +} + +static void put_user_huge_page(struct page *page) +{ + if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) { + struct page *endpage = page + HPAGE_PMD_NR; + + while (page < endpage) + put_page(page++); + } else { + put_page(page); + } +} + static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, @@ -948,6 +982,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, struct page *page, unsigned long haddr) { + struct mem_cgroup *memcg; spinlock_t *ptl; pgtable_t pgtable; pmd_t _pmd; @@ -968,20 +1003,21 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, __GFP_OTHER_NODE, vma, address, page_to_nid(page)); if (unlikely(!pages[i] || - mem_cgroup_charge_anon(pages[i], mm, - GFP_KERNEL))) { + mem_cgroup_try_charge(pages[i], mm, GFP_KERNEL, + &memcg))) { if (pages[i]) put_page(pages[i]); - mem_cgroup_uncharge_start(); while (--i >= 0) { - mem_cgroup_uncharge_page(pages[i]); + memcg = (void *)page_private(pages[i]); + set_page_private(pages[i], 0); + mem_cgroup_cancel_charge(pages[i], memcg); put_page(pages[i]); } - mem_cgroup_uncharge_end(); kfree(pages); ret |= VM_FAULT_OOM; goto out; } + set_page_private(pages[i], (unsigned long)memcg); } for (i = 0; i < HPAGE_PMD_NR; i++) { @@ -1010,7 +1046,11 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm, pte_t *pte, entry; entry = mk_pte(pages[i], vma->vm_page_prot); 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); + mem_cgroup_commit_charge(pages[i], memcg, false); + lru_cache_add_active_or_unevictable(pages[i], vma); pte = pte_offset_map(&_pmd, haddr); VM_BUG_ON(!pte_none(*pte)); set_pte_at(mm, haddr, pte, entry); @@ -1034,12 +1074,12 @@ out: out_free_pages: spin_unlock(ptl); mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); - mem_cgroup_uncharge_start(); for (i = 0; i < HPAGE_PMD_NR; i++) { - mem_cgroup_uncharge_page(pages[i]); + memcg = (void *)page_private(pages[i]); + set_page_private(pages[i], 0); + mem_cgroup_cancel_charge(pages[i], memcg); put_page(pages[i]); } - mem_cgroup_uncharge_end(); kfree(pages); goto out; } @@ -1050,6 +1090,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, spinlock_t *ptl; int ret = 0; struct page *page = NULL, *new_page; + struct mem_cgroup *memcg; unsigned long haddr; unsigned long mmun_start; /* For mmu_notifiers */ unsigned long mmun_end; /* For mmu_notifiers */ @@ -1074,7 +1115,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, ret |= VM_FAULT_WRITE; goto out_unlock; } - get_page(page); + get_user_huge_page(page); spin_unlock(ptl); alloc: if (transparent_hugepage_enabled(vma) && @@ -1095,17 +1136,18 @@ alloc: split_huge_page(page); ret |= VM_FAULT_FALLBACK; } - put_page(page); + put_user_huge_page(page); } count_vm_event(THP_FAULT_FALLBACK); goto out; } - if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) { + if (unlikely(mem_cgroup_try_charge(new_page, mm, + GFP_TRANSHUGE, &memcg))) { put_page(new_page); if (page) { split_huge_page(page); - put_page(page); + put_user_huge_page(page); } else split_huge_page_pmd(vma, address, pmd); ret |= VM_FAULT_FALLBACK; @@ -1127,10 +1169,10 @@ alloc: spin_lock(ptl); if (page) - put_page(page); + put_user_huge_page(page); if (unlikely(!pmd_same(*pmd, orig_pmd))) { spin_unlock(ptl); - mem_cgroup_uncharge_page(new_page); + mem_cgroup_cancel_charge(new_page, memcg); put_page(new_page); goto out_mn; } else { @@ -1139,6 +1181,8 @@ alloc: entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); pmdp_clear_flush(vma, haddr, pmd); page_add_new_anon_rmap(new_page, vma, haddr); + mem_cgroup_commit_charge(new_page, memcg, false); + lru_cache_add_active_or_unevictable(new_page, vma); set_pmd_at(mm, haddr, pmd, entry); update_mmu_cache_pmd(vma, address, pmd); if (!page) { @@ -1650,7 +1694,7 @@ static void __split_huge_page_refcount(struct page *page, &page_tail->_count); /* after clearing PageTail the gup refcount can be released */ - smp_mb(); + smp_mb__after_atomic(); /* * retain hwpoison flag of the poisoned tail page: @@ -1744,6 +1788,8 @@ static int __split_huge_page_map(struct page *page, if (pmd) { pgtable = pgtable_trans_huge_withdraw(mm, pmd); pmd_populate(mm, &_pmd, pgtable); + if (pmd_write(*pmd)) + BUG_ON(page_mapcount(page) != 1); haddr = address; for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { @@ -1753,8 +1799,6 @@ static int __split_huge_page_map(struct page *page, entry = maybe_mkwrite(pte_mkdirty(entry), vma); if (!pmd_write(*pmd)) entry = pte_wrprotect(entry); - else - BUG_ON(page_mapcount(page) != 1); if (!pmd_young(*pmd)) entry = pte_mkold(entry); if (pmd_numa(*pmd)) @@ -2202,6 +2246,30 @@ static void khugepaged_alloc_sleep(void) static int khugepaged_node_load[MAX_NUMNODES]; +static bool khugepaged_scan_abort(int nid) +{ + int i; + + /* + * If zone_reclaim_mode is disabled, then no extra effort is made to + * allocate memory locally. + */ + if (!zone_reclaim_mode) + return false; + + /* If there is a count for this node already, it must be acceptable */ + if (khugepaged_node_load[nid]) + return false; + + for (i = 0; i < MAX_NUMNODES; i++) { + if (!khugepaged_node_load[i]) + continue; + if (node_distance(nid, i) > RECLAIM_DISTANCE) + return true; + } + return false; +} + #ifdef CONFIG_NUMA static int khugepaged_find_target_node(void) { @@ -2358,6 +2426,7 @@ static void collapse_huge_page(struct mm_struct *mm, spinlock_t *pmd_ptl, *pte_ptl; int isolated; unsigned long hstart, hend; + struct mem_cgroup *memcg; unsigned long mmun_start; /* For mmu_notifiers */ unsigned long mmun_end; /* For mmu_notifiers */ @@ -2368,7 +2437,8 @@ static void collapse_huge_page(struct mm_struct *mm, if (!new_page) return; - if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) + if (unlikely(mem_cgroup_try_charge(new_page, mm, + GFP_TRANSHUGE, &memcg))) return; /* @@ -2392,8 +2462,6 @@ static void collapse_huge_page(struct mm_struct *mm, pmd = mm_find_pmd(mm, address); if (!pmd) goto out; - if (pmd_trans_huge(*pmd)) - goto out; anon_vma_lock_write(vma->anon_vma); @@ -2457,6 +2525,8 @@ 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); + mem_cgroup_commit_charge(new_page, memcg, false); + lru_cache_add_active_or_unevictable(new_page, vma); pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, address, pmd, _pmd); update_mmu_cache_pmd(vma, address, pmd); @@ -2470,7 +2540,7 @@ out_up_write: return; out: - mem_cgroup_uncharge_page(new_page); + mem_cgroup_cancel_charge(new_page, memcg); goto out_up_write; } @@ -2492,8 +2562,6 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, pmd = mm_find_pmd(mm, address); if (!pmd) goto out; - if (pmd_trans_huge(*pmd)) - goto out; memset(khugepaged_node_load, 0, sizeof(khugepaged_node_load)); pte = pte_offset_map_lock(mm, pmd, address, &ptl); @@ -2518,6 +2586,8 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, * hit record. */ node = page_to_nid(page); + if (khugepaged_scan_abort(node)) + goto out_unmap; khugepaged_node_load[node]++; VM_BUG_ON_PAGE(PageCompound(page), page); if (!PageLRU(page) || PageLocked(page) || !PageAnon(page)) @@ -2846,12 +2916,22 @@ void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address, static void split_huge_page_address(struct mm_struct *mm, unsigned long address) { + pgd_t *pgd; + pud_t *pud; pmd_t *pmd; VM_BUG_ON(!(address & ~HPAGE_PMD_MASK)); - pmd = mm_find_pmd(mm, address); - if (!pmd) + pgd = pgd_offset(mm, address); + if (!pgd_present(*pgd)) + return; + + pud = pud_offset(pgd, address); + if (!pud_present(*pud)) + return; + + pmd = pmd_offset(pud, address); + if (!pmd_present(*pmd)) return; /* * Caller holds the mmap_sem write mode, so a huge pmd cannot |