diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 33 |
1 files changed, 15 insertions, 18 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 08fc0ba2207e..1ea21e203a70 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1700,7 +1700,8 @@ bool move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_vma, pmd = pmdp_huge_get_and_clear(mm, old_addr, old_pmd); VM_BUG_ON(!pmd_none(*new_pmd)); - if (pmd_move_must_withdraw(new_ptl, old_ptl)) { + if (pmd_move_must_withdraw(new_ptl, old_ptl) && + vma_is_anonymous(vma)) { pgtable_t pgtable; pgtable = pgtable_trans_huge_withdraw(mm, old_pmd); pgtable_trans_huge_deposit(mm, new_pmd, pgtable); @@ -2835,6 +2836,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pgtable_t pgtable; pmd_t _pmd; bool young, write, dirty; + unsigned long addr; int i; VM_BUG_ON(haddr & ~HPAGE_PMD_MASK); @@ -2860,10 +2862,11 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, young = pmd_young(*pmd); dirty = pmd_dirty(*pmd); + pmdp_huge_split_prepare(vma, haddr, pmd); pgtable = pgtable_trans_huge_withdraw(mm, pmd); pmd_populate(mm, &_pmd, pgtable); - for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { + for (i = 0, addr = haddr; i < HPAGE_PMD_NR; i++, addr += PAGE_SIZE) { pte_t entry, *pte; /* * Note that NUMA hinting access restrictions are not @@ -2884,9 +2887,9 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, } if (dirty) SetPageDirty(page + i); - pte = pte_offset_map(&_pmd, haddr); + pte = pte_offset_map(&_pmd, addr); BUG_ON(!pte_none(*pte)); - set_pte_at(mm, haddr, pte, entry); + set_pte_at(mm, addr, pte, entry); atomic_inc(&page[i]._mapcount); pte_unmap(pte); } @@ -2936,7 +2939,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pmd_populate(mm, pmd, pgtable); if (freeze) { - for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { + for (i = 0; i < HPAGE_PMD_NR; i++) { page_remove_rmap(page + i, false); put_page(page + i); } @@ -3217,28 +3220,26 @@ static void unfreeze_page(struct anon_vma *anon_vma, struct page *page) } } -static int __split_huge_page_tail(struct page *head, int tail, +static void __split_huge_page_tail(struct page *head, int tail, struct lruvec *lruvec, struct list_head *list) { - int mapcount; struct page *page_tail = head + tail; - mapcount = atomic_read(&page_tail->_mapcount) + 1; + VM_BUG_ON_PAGE(atomic_read(&page_tail->_mapcount) != -1, page_tail); VM_BUG_ON_PAGE(atomic_read(&page_tail->_count) != 0, page_tail); /* * tail_page->_count is zero and not changing from under us. But * get_page_unless_zero() may be running from under us on the - * tail_page. If we used atomic_set() below instead of atomic_add(), we + * tail_page. If we used atomic_set() below instead of atomic_inc(), we * would then run atomic_set() concurrently with * get_page_unless_zero(), and atomic_set() is implemented in C not * using locked ops. spin_unlock on x86 sometime uses locked ops * because of PPro errata 66, 92, so unless somebody can guarantee * atomic_set() here would be safe on all archs (and not only on x86), - * it's safer to use atomic_add(). + * it's safer to use atomic_inc(). */ - atomic_add(mapcount + 1, &page_tail->_count); - + atomic_inc(&page_tail->_count); page_tail->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; page_tail->flags |= (head->flags & @@ -3272,8 +3273,6 @@ static int __split_huge_page_tail(struct page *head, int tail, page_tail->index = head->index + tail; page_cpupid_xchg_last(page_tail, page_cpupid_last(head)); lru_add_page_tail(head, page_tail, lruvec, list); - - return mapcount; } static void __split_huge_page(struct page *page, struct list_head *list) @@ -3281,7 +3280,7 @@ static void __split_huge_page(struct page *page, struct list_head *list) struct page *head = compound_head(page); struct zone *zone = page_zone(head); struct lruvec *lruvec; - int i, tail_mapcount; + int i; /* prevent PageLRU to go away from under us, and freeze lru stats */ spin_lock_irq(&zone->lru_lock); @@ -3290,10 +3289,8 @@ static void __split_huge_page(struct page *page, struct list_head *list) /* complete memcg works before add pages to LRU */ mem_cgroup_split_huge_fixup(head); - tail_mapcount = 0; for (i = HPAGE_PMD_NR - 1; i >= 1; i--) - tail_mapcount += __split_huge_page_tail(head, i, lruvec, list); - atomic_sub(tail_mapcount, &head->_count); + __split_huge_page_tail(head, i, lruvec, list); ClearPageCompound(head); spin_unlock_irq(&zone->lru_lock); |