diff options
| -rw-r--r-- | include/linux/shmem_fs.h | 1 | ||||
| -rw-r--r-- | include/linux/swap.h | 2 | ||||
| -rw-r--r-- | ipc/shm.c | 2 | ||||
| -rw-r--r-- | mm/shmem.c | 46 | ||||
| -rw-r--r-- | mm/vmscan.c | 122 |
5 files changed, 81 insertions, 92 deletions
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 9291ac3cc62..6f10c9cae3d 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -48,6 +48,7 @@ extern struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags); extern int shmem_zero_setup(struct vm_area_struct *); extern int shmem_lock(struct file *file, int lock, struct user_struct *user); +extern void shmem_unlock_mapping(struct address_space *mapping); extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping, pgoff_t index, gfp_t gfp_mask); extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end); diff --git a/include/linux/swap.h b/include/linux/swap.h index 1e22e126d2a..67b3fa30898 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -272,7 +272,7 @@ static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order) #endif extern int page_evictable(struct page *page, struct vm_area_struct *vma); -extern void scan_mapping_unevictable_pages(struct address_space *); +extern void check_move_unevictable_pages(struct page **, int nr_pages); extern unsigned long scan_unevictable_pages; extern int scan_unevictable_handler(struct ctl_table *, int, diff --git a/ipc/shm.c b/ipc/shm.c index 854ab58e5f6..b76be5bda6c 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -916,7 +916,7 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) shp->mlock_user = NULL; get_file(shm_file); shm_unlock(shp); - scan_mapping_unevictable_pages(shm_file->f_mapping); + shmem_unlock_mapping(shm_file->f_mapping); fput(shm_file); goto out; } diff --git a/mm/shmem.c b/mm/shmem.c index cc6d40b2892..6c253f75387 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -379,7 +379,7 @@ static int shmem_free_swap(struct address_space *mapping, /* * Pagevec may contain swap entries, so shuffle up pages before releasing. */ -static void shmem_pagevec_release(struct pagevec *pvec) +static void shmem_deswap_pagevec(struct pagevec *pvec) { int i, j; @@ -389,7 +389,36 @@ static void shmem_pagevec_release(struct pagevec *pvec) pvec->pages[j++] = page; } pvec->nr = j; - pagevec_release(pvec); +} + +/* + * SysV IPC SHM_UNLOCK restore Unevictable pages to their evictable lists. + */ +void shmem_unlock_mapping(struct address_space *mapping) +{ + struct pagevec pvec; + pgoff_t indices[PAGEVEC_SIZE]; + pgoff_t index = 0; + + pagevec_init(&pvec, 0); + /* + * Minor point, but we might as well stop if someone else SHM_LOCKs it. + */ + while (!mapping_unevictable(mapping)) { + /* + * Avoid pagevec_lookup(): find_get_pages() returns 0 as if it + * has finished, if it hits a row of PAGEVEC_SIZE swap entries. + */ + pvec.nr = shmem_find_get_pages_and_swap(mapping, index, + PAGEVEC_SIZE, pvec.pages, indices); + if (!pvec.nr) + break; + index = indices[pvec.nr - 1] + 1; + shmem_deswap_pagevec(&pvec); + check_move_unevictable_pages(pvec.pages, pvec.nr); + pagevec_release(&pvec); + cond_resched(); + } } /* @@ -440,7 +469,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) } unlock_page(page); } - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); mem_cgroup_uncharge_end(); cond_resched(); index++; @@ -470,7 +500,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) continue; } if (index == start && indices[0] > end) { - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); break; } mem_cgroup_uncharge_start(); @@ -494,7 +525,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) } unlock_page(page); } - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); mem_cgroup_uncharge_end(); index++; } @@ -2439,6 +2471,10 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user) return 0; } +void shmem_unlock_mapping(struct address_space *mapping) +{ +} + void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) { truncate_inode_pages_range(inode->i_mapping, lstart, lend); diff --git a/mm/vmscan.c b/mm/vmscan.c index 824676a4ca7..cb33d9cd4d6 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -636,7 +636,7 @@ redo: * When racing with an mlock or AS_UNEVICTABLE clearing * (page is unlocked) make sure that if the other thread * does not observe our setting of PG_lru and fails - * isolation/check_move_unevictable_page, + * isolation/check_move_unevictable_pages, * we see PG_mlocked/AS_UNEVICTABLE cleared below and move * the page back to the evictable list. * @@ -3355,104 +3355,56 @@ int page_evictable(struct page *page, struct vm_area_struct *vma) #ifdef CONFIG_SHMEM /** - * check_move_unevictable_page - check page for evictability and move to appropriate zone lru list - * @page: page to check evictability and move to appropriate lru list - * @zone: zone page is in + * check_move_unevictable_pages - check pages for evictability and move to appropriate zone lru list + * @pages: array of pages to check + * @nr_pages: number of pages to check * - * Checks a page for evictability and moves the page to the appropriate - * zone lru list. - * - * Restrictions: zone->lru_lock must be held, page must be on LRU and must - * have PageUnevictable set. + * Checks pages for evictability and moves them to the appropriate lru list. * * This function is only used for SysV IPC SHM_UNLOCK. */ -static void check_move_unevictable_page(struct page *page, struct zone *zone) +void check_move_unevictable_pages(struct page **pages, int nr_pages) { - VM_BUG_ON(PageActive(page)); + struct zone *zone = NULL; + int pgscanned = 0; + int pgrescued = 0; + int i; -retry: - ClearPageUnevictable(page); - if (page_evictable(page, NULL)) { - enum lru_list l = page_lru_base_type(page); + for (i = 0; i < nr_pages; i++) { + struct page *page = pages[i]; + struct zone *pagezone; - __dec_zone_state(zone, NR_UNEVICTABLE); - list_move(&page->lru, &zone->lru[l].list); - mem_cgroup_move_lists(page, LRU_UNEVICTABLE, l); - __inc_zone_state(zone, NR_INACTIVE_ANON + l); - __count_vm_event(UNEVICTABLE_PGRESCUED); - } else { - /* - * rotate unevictable list - */ - SetPageUnevictable(page); - list_move(&page->lru, &zone->lru[LRU_UNEVICTABLE].list); - mem_cgroup_rotate_lru_list(page, LRU_UNEVICTABLE); - if (page_evictable(page, NULL)) - goto retry; - } -} - -/** - * scan_mapping_unevictable_pages - scan an address space for evictable pages - * @mapping: struct address_space to scan for evictable pages - * - * Scan all pages in mapping. Check unevictable pages for - * evictability and move them to the appropriate zone lru list. - * - * This function is only used for SysV IPC SHM_UNLOCK. - */ -void scan_mapping_unevictable_pages(struct address_space *mapping) -{ - pgoff_t next = 0; - pgoff_t end = (i_size_read(mapping->host) + PAGE_CACHE_SIZE - 1) >> - PAGE_CACHE_SHIFT; - struct zone *zone; - struct pagevec pvec; + pgscanned++; + pagezone = page_zone(page); + if (pagezone != zone) { + if (zone) + spin_unlock_irq(&zone->lru_lock); + zone = pagezone; + spin_lock_irq(&zone->lru_lock); + } - if (mapping->nrpages == 0) - return; + if (!PageLRU(page) || !PageUnevictable(page)) + continue; - pagevec_init(&pvec, 0); - while (next < end && - pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { - int i; - int pg_scanned = 0; - - zone = NULL; - - for (i = 0; i < pagevec_count(&pvec); i++) { - struct page *page = pvec.pages[i]; - pgoff_t page_index = page->index; - struct zone *pagezone = page_zone(page); - - pg_scanned++; - if (page_index > next) - next = page_index; - next++; - - if (pagezone != zone) { - if (zone) - spin_unlock_irq(&zone->lru_lock); - zone = pagezone; - spin_lock_irq(&zone->lru_lock); - } + if (page_evictable(page, NULL)) { + enum lru_list lru = page_lru_base_type(page); - if (PageLRU(page) && PageUnevictable(page)) - check_move_unevictable_page(page, zone); + VM_BUG_ON(PageActive(page)); + ClearPageUnevictable(page); + __dec_zone_state(zone, NR_UNEVICTABLE); + list_move(&page->lru, &zone->lru[lru].list); + mem_cgroup_move_lists(page, LRU_UNEVICTABLE, lru); + __inc_zone_state(zone, NR_INACTIVE_ANON + lru); + pgrescued++; } - if (zone) - spin_unlock_irq(&zone->lru_lock); - pagevec_release(&pvec); + } - count_vm_events(UNEVICTABLE_PGSCANNED, pg_scanned); - cond_resched(); + if (zone) { + __count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued); + __count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); + spin_unlock_irq(&zone->lru_lock); } } -#else -void scan_mapping_unevictable_pages(struct address_space *mapping) -{ -} #endif /* CONFIG_SHMEM */ static void warn_scan_unevictable_pages(void) |