1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/spinlock.h>
6 #include <linux/linkage.h>
7 #include <linux/mmzone.h>
8 #include <linux/list.h>
9 #include <linux/memcontrol.h>
10 #include <linux/sched.h>
11 #include <linux/node.h>
13 #include <linux/pagemap.h>
14 #include <linux/atomic.h>
15 #include <linux/page-flags.h>
16 #include <uapi/linux/mempolicy.h>
19 struct notifier_block;
25 #define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
26 #define SWAP_FLAG_PRIO_MASK 0x7fff
27 #define SWAP_FLAG_PRIO_SHIFT 0
28 #define SWAP_FLAG_DISCARD 0x10000 /* enable discard for swap */
29 #define SWAP_FLAG_DISCARD_ONCE 0x20000 /* discard swap area at swapon-time */
30 #define SWAP_FLAG_DISCARD_PAGES 0x40000 /* discard page-clusters after use */
32 #define SWAP_FLAGS_VALID (SWAP_FLAG_PRIO_MASK | SWAP_FLAG_PREFER | \
33 SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | \
34 SWAP_FLAG_DISCARD_PAGES)
37 static inline int current_is_kswapd(void)
39 return current->flags & PF_KSWAPD;
43 * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
44 * be swapped to. The swap type and the offset into that swap type are
45 * encoded into pte's and into pgoff_t's in the swapcache. Using five bits
46 * for the type means that the maximum number of swapcache pages is 27 bits
47 * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
48 * the type/offset into the pte as 5/27 as well.
50 #define MAX_SWAPFILES_SHIFT 5
53 * Use some of the swap files numbers for other purposes. This
54 * is a convenient way to hook into the VM to trigger special
59 * Unaddressable device memory support. See include/linux/hmm.h and
60 * Documentation/vm/hmm.rst. Short description is we need struct pages for
61 * device memory that is unaddressable (inaccessible) by CPU, so that we can
62 * migrate part of a process memory to device memory.
64 * When a page is migrated from CPU to device, we set the CPU page table entry
65 * to a special SWP_DEVICE_* entry.
67 #ifdef CONFIG_DEVICE_PRIVATE
68 #define SWP_DEVICE_NUM 2
69 #define SWP_DEVICE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM)
70 #define SWP_DEVICE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+1)
72 #define SWP_DEVICE_NUM 0
76 * NUMA node memory migration support
78 #ifdef CONFIG_MIGRATION
79 #define SWP_MIGRATION_NUM 2
80 #define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM)
81 #define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1)
83 #define SWP_MIGRATION_NUM 0
87 * Handling of hardware poisoned pages with memory corruption.
89 #ifdef CONFIG_MEMORY_FAILURE
90 #define SWP_HWPOISON_NUM 1
91 #define SWP_HWPOISON MAX_SWAPFILES
93 #define SWP_HWPOISON_NUM 0
96 #define MAX_SWAPFILES \
97 ((1 << MAX_SWAPFILES_SHIFT) - SWP_DEVICE_NUM - \
98 SWP_MIGRATION_NUM - SWP_HWPOISON_NUM)
101 * Magic header for a swap area. The first part of the union is
102 * what the swap magic looks like for the old (limited to 128MB)
103 * swap area format, the second part of the union adds - in the
104 * old reserved area - some extra information. Note that the first
105 * kilobyte is reserved for boot loader or disk label stuff...
107 * Having the magic at the end of the PAGE_SIZE makes detecting swap
108 * areas somewhat tricky on machines that support multiple page sizes.
109 * For 2.5 we'll probably want to move the magic to just beyond the
114 char reserved[PAGE_SIZE - 10];
115 char magic[10]; /* SWAP-SPACE or SWAPSPACE2 */
118 char bootbits[1024]; /* Space for disklabel etc. */
122 unsigned char sws_uuid[16];
123 unsigned char sws_volume[16];
130 * current->reclaim_state points to one of these when a task is running
133 struct reclaim_state {
134 unsigned long reclaimed_slab;
139 struct address_space;
141 struct writeback_control;
145 * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
146 * disk blocks. A list of swap extents maps the entire swapfile. (Where the
147 * term `swapfile' refers to either a blockdevice or an IS_REG file. Apart
148 * from setup, they're handled identically.
150 * We always assume that blocks are of size PAGE_SIZE.
153 struct rb_node rb_node;
156 sector_t start_block;
160 * Max bad pages in the new format..
162 #define MAX_SWAP_BADPAGES \
163 ((offsetof(union swap_header, magic.magic) - \
164 offsetof(union swap_header, info.badpages)) / sizeof(int))
167 SWP_USED = (1 << 0), /* is slot in swap_info[] used? */
168 SWP_WRITEOK = (1 << 1), /* ok to write to this swap? */
169 SWP_DISCARDABLE = (1 << 2), /* blkdev support discard */
170 SWP_DISCARDING = (1 << 3), /* now discarding a free cluster */
171 SWP_SOLIDSTATE = (1 << 4), /* blkdev seeks are cheap */
172 SWP_CONTINUED = (1 << 5), /* swap_map has count continuation */
173 SWP_BLKDEV = (1 << 6), /* its a block device */
174 SWP_ACTIVATED = (1 << 7), /* set after swap_activate success */
175 SWP_FS_OPS = (1 << 8), /* swapfile operations go through fs */
176 SWP_AREA_DISCARD = (1 << 9), /* single-time swap area discards */
177 SWP_PAGE_DISCARD = (1 << 10), /* freed swap page-cluster discards */
178 SWP_STABLE_WRITES = (1 << 11), /* no overwrite PG_writeback pages */
179 SWP_SYNCHRONOUS_IO = (1 << 12), /* synchronous IO is efficient */
180 SWP_VALID = (1 << 13), /* swap is valid to be operated on? */
181 /* add others here before... */
182 SWP_SCANNING = (1 << 14), /* refcount in scan_swap_map */
185 #define SWAP_CLUSTER_MAX 32UL
186 #define COMPACT_CLUSTER_MAX SWAP_CLUSTER_MAX
188 /* Bit flag in swap_map */
189 #define SWAP_HAS_CACHE 0x40 /* Flag page is cached, in first swap_map */
190 #define COUNT_CONTINUED 0x80 /* Flag swap_map continuation for full count */
192 /* Special value in first swap_map */
193 #define SWAP_MAP_MAX 0x3e /* Max count */
194 #define SWAP_MAP_BAD 0x3f /* Note page is bad */
195 #define SWAP_MAP_SHMEM 0xbf /* Owned by shmem/tmpfs */
197 /* Special value in each swap_map continuation */
198 #define SWAP_CONT_MAX 0x7f /* Max count */
201 * We use this to track usage of a cluster. A cluster is a block of swap disk
202 * space with SWAPFILE_CLUSTER pages long and naturally aligns in disk. All
203 * free clusters are organized into a list. We fetch an entry from the list to
204 * get a free cluster.
206 * The data field stores next cluster if the cluster is free or cluster usage
207 * counter otherwise. The flags field determines if a cluster is free. This is
208 * protected by swap_info_struct.lock.
210 struct swap_cluster_info {
212 * Protect swap_cluster_info fields
213 * and swap_info_struct->swap_map
214 * elements correspond to the swap
217 unsigned int data:24;
218 unsigned int flags:8;
220 #define CLUSTER_FLAG_FREE 1 /* This cluster is free */
221 #define CLUSTER_FLAG_NEXT_NULL 2 /* This cluster has no next cluster */
222 #define CLUSTER_FLAG_HUGE 4 /* This cluster is backing a transparent huge page */
225 * We assign a cluster to each CPU, so each CPU can allocate swap entry from
226 * its own cluster and swapout sequentially. The purpose is to optimize swapout
229 struct percpu_cluster {
230 struct swap_cluster_info index; /* Current cluster index */
231 unsigned int next; /* Likely next allocation offset */
234 struct swap_cluster_list {
235 struct swap_cluster_info head;
236 struct swap_cluster_info tail;
240 * The in-memory structure used to track swap areas.
242 struct swap_info_struct {
243 unsigned long flags; /* SWP_USED etc: see above */
244 signed short prio; /* swap priority of this type */
245 struct plist_node list; /* entry in swap_active_head */
246 signed char type; /* strange name for an index */
247 unsigned int max; /* extent of the swap_map */
248 unsigned char *swap_map; /* vmalloc'ed array of usage counts */
249 struct swap_cluster_info *cluster_info; /* cluster info. Only for SSD */
250 struct swap_cluster_list free_clusters; /* free clusters list */
251 unsigned int lowest_bit; /* index of first free in swap_map */
252 unsigned int highest_bit; /* index of last free in swap_map */
253 unsigned int pages; /* total of usable pages of swap */
254 unsigned int inuse_pages; /* number of those currently in use */
255 unsigned int cluster_next; /* likely index for next allocation */
256 unsigned int cluster_nr; /* countdown to next cluster search */
257 unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */
258 struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
259 struct rb_root swap_extent_root;/* root of the swap extent rbtree */
260 struct block_device *bdev; /* swap device or bdev of swap file */
261 struct file *swap_file; /* seldom referenced */
262 unsigned int old_block_size; /* seldom referenced */
263 #ifdef CONFIG_FRONTSWAP
264 unsigned long *frontswap_map; /* frontswap in-use, one bit per page */
265 atomic_t frontswap_pages; /* frontswap pages in-use counter */
268 * protect map scan related fields like
269 * swap_map, lowest_bit, highest_bit,
270 * inuse_pages, cluster_next,
271 * cluster_nr, lowest_alloc,
272 * highest_alloc, free/discard cluster
273 * list. other fields are only changed
274 * at swapon/swapoff, so are protected
275 * by swap_lock. changing flags need
276 * hold this lock and swap_lock. If
277 * both locks need hold, hold swap_lock
280 spinlock_t cont_lock; /*
281 * protect swap count continuation page
284 struct work_struct discard_work; /* discard worker */
285 struct swap_cluster_list discard_clusters; /* discard clusters list */
286 struct plist_node avail_lists[]; /*
287 * entries in swap_avail_heads, one
289 * Must be last as the number of the
290 * array is nr_node_ids, which is not
291 * a fixed value so have to allocate
293 * And it has to be an array so that
294 * plist_for_each_* can work.
299 #define SWAP_RA_ORDER_CEILING 5
301 /* Avoid stack overflow, because we need to save part of page table */
302 #define SWAP_RA_ORDER_CEILING 3
303 #define SWAP_RA_PTE_CACHE_SIZE (1 << SWAP_RA_ORDER_CEILING)
306 struct vma_swap_readahead {
308 unsigned short offset;
309 unsigned short nr_pte;
313 pte_t ptes[SWAP_RA_PTE_CACHE_SIZE];
317 /* linux/mm/workingset.c */
318 void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages);
319 void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg);
320 void workingset_refault(struct page *page, void *shadow);
321 void workingset_activation(struct page *page);
323 /* Only track the nodes of mappings with shadow entries */
324 void workingset_update_node(struct xa_node *node);
325 #define mapping_set_update(xas, mapping) do { \
326 if (!dax_mapping(mapping) && !shmem_mapping(mapping)) \
327 xas_set_update(xas, workingset_update_node); \
330 /* linux/mm/page_alloc.c */
331 extern unsigned long totalreserve_pages;
332 extern unsigned long nr_free_buffer_pages(void);
334 /* Definition of global_zone_page_state not available yet */
335 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
338 /* linux/mm/swap.c */
339 extern void lru_note_cost(struct lruvec *lruvec, bool file,
340 unsigned int nr_pages);
341 extern void lru_note_cost_page(struct page *);
342 extern void lru_cache_add(struct page *);
343 extern void mark_page_accessed(struct page *);
345 extern atomic_t lru_disable_count;
347 static inline bool lru_cache_disabled(void)
349 return atomic_read(&lru_disable_count);
352 static inline void lru_cache_enable(void)
354 atomic_dec(&lru_disable_count);
357 extern void lru_cache_disable(void);
358 extern void lru_add_drain(void);
359 extern void lru_add_drain_cpu(int cpu);
360 extern void lru_add_drain_cpu_zone(struct zone *zone);
361 extern void lru_add_drain_all(void);
362 extern void rotate_reclaimable_page(struct page *page);
363 extern void deactivate_file_page(struct page *page);
364 extern void deactivate_page(struct page *page);
365 extern void mark_page_lazyfree(struct page *page);
366 extern void swap_setup(void);
368 extern void lru_cache_add_inactive_or_unevictable(struct page *page,
369 struct vm_area_struct *vma);
371 /* linux/mm/vmscan.c */
372 extern unsigned long zone_reclaimable_pages(struct zone *zone);
373 extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
374 gfp_t gfp_mask, nodemask_t *mask);
375 extern bool __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode);
376 extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
377 unsigned long nr_pages,
380 extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
381 gfp_t gfp_mask, bool noswap,
383 unsigned long *nr_scanned);
384 extern unsigned long shrink_all_memory(unsigned long nr_pages);
385 extern int vm_swappiness;
386 extern int remove_mapping(struct address_space *mapping, struct page *page);
388 extern unsigned long reclaim_pages(struct list_head *page_list);
390 extern int node_reclaim_mode;
391 extern int sysctl_min_unmapped_ratio;
392 extern int sysctl_min_slab_ratio;
394 #define node_reclaim_mode 0
397 static inline bool node_reclaim_enabled(void)
399 /* Is any node_reclaim_mode bit set? */
400 return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP);
403 extern void check_move_unevictable_pages(struct pagevec *pvec);
405 extern int kswapd_run(int nid);
406 extern void kswapd_stop(int nid);
410 #include <linux/blk_types.h> /* for bio_end_io_t */
412 /* linux/mm/page_io.c */
413 extern int swap_readpage(struct page *page, bool do_poll);
414 extern int swap_writepage(struct page *page, struct writeback_control *wbc);
415 extern void end_swap_bio_write(struct bio *bio);
416 extern int __swap_writepage(struct page *page, struct writeback_control *wbc,
417 bio_end_io_t end_write_func);
418 extern int swap_set_page_dirty(struct page *page);
420 int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page,
421 unsigned long nr_pages, sector_t start_block);
422 int generic_swapfile_activate(struct swap_info_struct *, struct file *,
425 /* linux/mm/swap_state.c */
426 /* One swap address space for each 64M swap space */
427 #define SWAP_ADDRESS_SPACE_SHIFT 14
428 #define SWAP_ADDRESS_SPACE_PAGES (1 << SWAP_ADDRESS_SPACE_SHIFT)
429 extern struct address_space *swapper_spaces[];
430 #define swap_address_space(entry) \
431 (&swapper_spaces[swp_type(entry)][swp_offset(entry) \
432 >> SWAP_ADDRESS_SPACE_SHIFT])
433 static inline unsigned long total_swapcache_pages(void)
435 return global_node_page_state(NR_SWAPCACHE);
438 extern void show_swap_cache_info(void);
439 extern int add_to_swap(struct page *page);
440 extern void *get_shadow_from_swap_cache(swp_entry_t entry);
441 extern int add_to_swap_cache(struct page *page, swp_entry_t entry,
442 gfp_t gfp, void **shadowp);
443 extern void __delete_from_swap_cache(struct page *page,
444 swp_entry_t entry, void *shadow);
445 extern void delete_from_swap_cache(struct page *);
446 extern void clear_shadow_from_swap_cache(int type, unsigned long begin,
448 extern void free_page_and_swap_cache(struct page *);
449 extern void free_pages_and_swap_cache(struct page **, int);
450 extern struct page *lookup_swap_cache(swp_entry_t entry,
451 struct vm_area_struct *vma,
453 struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index);
454 extern struct page *read_swap_cache_async(swp_entry_t, gfp_t,
455 struct vm_area_struct *vma, unsigned long addr,
457 extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
458 struct vm_area_struct *vma, unsigned long addr,
459 bool *new_page_allocated);
460 extern struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
461 struct vm_fault *vmf);
462 extern struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
463 struct vm_fault *vmf);
465 /* linux/mm/swapfile.c */
466 extern atomic_long_t nr_swap_pages;
467 extern long total_swap_pages;
468 extern atomic_t nr_rotate_swap;
469 extern bool has_usable_swap(void);
471 /* Swap 50% full? Release swapcache more aggressively.. */
472 static inline bool vm_swap_full(void)
474 return atomic_long_read(&nr_swap_pages) * 2 < total_swap_pages;
477 static inline long get_nr_swap_pages(void)
479 return atomic_long_read(&nr_swap_pages);
482 extern void si_swapinfo(struct sysinfo *);
483 extern swp_entry_t get_swap_page(struct page *page);
484 extern void put_swap_page(struct page *page, swp_entry_t entry);
485 extern swp_entry_t get_swap_page_of_type(int);
486 extern int get_swap_pages(int n, swp_entry_t swp_entries[], int entry_size);
487 extern int add_swap_count_continuation(swp_entry_t, gfp_t);
488 extern void swap_shmem_alloc(swp_entry_t);
489 extern int swap_duplicate(swp_entry_t);
490 extern int swapcache_prepare(swp_entry_t);
491 extern void swap_free(swp_entry_t);
492 extern void swapcache_free_entries(swp_entry_t *entries, int n);
493 extern int free_swap_and_cache(swp_entry_t);
494 int swap_type_of(dev_t device, sector_t offset);
495 int find_first_swap(dev_t *device);
496 extern unsigned int count_swap_pages(int, int);
497 extern sector_t swapdev_block(int, pgoff_t);
498 extern int page_swapcount(struct page *);
499 extern int __swap_count(swp_entry_t entry);
500 extern int __swp_swapcount(swp_entry_t entry);
501 extern int swp_swapcount(swp_entry_t entry);
502 extern struct swap_info_struct *page_swap_info(struct page *);
503 extern struct swap_info_struct *swp_swap_info(swp_entry_t entry);
504 extern bool reuse_swap_page(struct page *, int *);
505 extern int try_to_free_swap(struct page *);
506 struct backing_dev_info;
507 extern int init_swap_address_space(unsigned int type, unsigned long nr_pages);
508 extern void exit_swap_address_space(unsigned int type);
509 extern struct swap_info_struct *get_swap_device(swp_entry_t entry);
510 sector_t swap_page_sector(struct page *page);
512 static inline void put_swap_device(struct swap_info_struct *si)
517 #else /* CONFIG_SWAP */
519 static inline int swap_readpage(struct page *page, bool do_poll)
524 static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry)
529 #define swap_address_space(entry) (NULL)
530 #define get_nr_swap_pages() 0L
531 #define total_swap_pages 0L
532 #define total_swapcache_pages() 0UL
533 #define vm_swap_full() 0
535 #define si_swapinfo(val) \
536 do { (val)->freeswap = (val)->totalswap = 0; } while (0)
537 /* only sparc can not include linux/pagemap.h in this file
538 * so leave put_page and release_pages undeclared... */
539 #define free_page_and_swap_cache(page) \
541 #define free_pages_and_swap_cache(pages, nr) \
542 release_pages((pages), (nr));
544 static inline void show_swap_cache_info(void)
548 #define free_swap_and_cache(e) ({(is_migration_entry(e) || is_device_private_entry(e));})
549 #define swapcache_prepare(e) ({(is_migration_entry(e) || is_device_private_entry(e));})
551 static inline int add_swap_count_continuation(swp_entry_t swp, gfp_t gfp_mask)
556 static inline void swap_shmem_alloc(swp_entry_t swp)
560 static inline int swap_duplicate(swp_entry_t swp)
565 static inline void swap_free(swp_entry_t swp)
569 static inline void put_swap_page(struct page *page, swp_entry_t swp)
573 static inline struct page *swap_cluster_readahead(swp_entry_t entry,
574 gfp_t gfp_mask, struct vm_fault *vmf)
579 static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
580 struct vm_fault *vmf)
585 static inline int swap_writepage(struct page *p, struct writeback_control *wbc)
590 static inline struct page *lookup_swap_cache(swp_entry_t swp,
591 struct vm_area_struct *vma,
598 struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index)
600 return find_get_page(mapping, index);
603 static inline int add_to_swap(struct page *page)
608 static inline void *get_shadow_from_swap_cache(swp_entry_t entry)
613 static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
614 gfp_t gfp_mask, void **shadowp)
619 static inline void __delete_from_swap_cache(struct page *page,
620 swp_entry_t entry, void *shadow)
624 static inline void delete_from_swap_cache(struct page *page)
628 static inline void clear_shadow_from_swap_cache(int type, unsigned long begin,
633 static inline int page_swapcount(struct page *page)
638 static inline int __swap_count(swp_entry_t entry)
643 static inline int __swp_swapcount(swp_entry_t entry)
648 static inline int swp_swapcount(swp_entry_t entry)
653 #define reuse_swap_page(page, total_map_swapcount) \
654 (page_trans_huge_mapcount(page, total_map_swapcount) == 1)
656 static inline int try_to_free_swap(struct page *page)
661 static inline swp_entry_t get_swap_page(struct page *page)
668 #endif /* CONFIG_SWAP */
670 #ifdef CONFIG_THP_SWAP
671 extern int split_swap_cluster(swp_entry_t entry);
673 static inline int split_swap_cluster(swp_entry_t entry)
680 static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg)
682 /* Cgroup2 doesn't have per-cgroup swappiness */
683 if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
684 return vm_swappiness;
687 if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg))
688 return vm_swappiness;
690 return memcg->swappiness;
693 static inline int mem_cgroup_swappiness(struct mem_cgroup *mem)
695 return vm_swappiness;
699 #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
700 extern void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask);
702 static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
707 #ifdef CONFIG_MEMCG_SWAP
708 extern void mem_cgroup_swapout(struct page *page, swp_entry_t entry);
709 extern int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry);
710 extern void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages);
711 extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg);
712 extern bool mem_cgroup_swap_full(struct page *page);
714 static inline void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
718 static inline int mem_cgroup_try_charge_swap(struct page *page,
724 static inline void mem_cgroup_uncharge_swap(swp_entry_t entry,
725 unsigned int nr_pages)
729 static inline long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
731 return get_nr_swap_pages();
734 static inline bool mem_cgroup_swap_full(struct page *page)
736 return vm_swap_full();
740 #endif /* __KERNEL__*/
741 #endif /* _LINUX_SWAP_H */