include/linux/mm_inline.h

   1 #ifndef LINUX_MM_INLINE_H
   2 #define LINUX_MM_INLINE_H
   3
   4 /**
   5  * page_is_file_cache - should the page be on a file LRU or anon LRU?
   6  * @page: the page to test
   7  *
   8  * Returns 1 if @page is page cache page backed by a regular filesystem,
   9  * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed.
  10  * Used by functions that manipulate the LRU lists, to sort a page
  11  * onto the right LRU list.
  12  *
  13  * We would like to get this info without a page flag, but the state
  14  * needs to survive until the page is last deleted from the LRU, which
  15  * could be as far down as __page_cache_release.
  16  */
  17 static inline int page_is_file_cache(struct page *page)
  18 {
  19         return !PageSwapBacked(page);
  20 }
  21
  22 static inline void
  23 __add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l,
  24                        struct list_head *head)
  25 {
  26         list_add(&page->lru, head);
  27         __inc_zone_state(zone, NR_LRU_BASE + l);
  28         mem_cgroup_add_lru_list(page, l);
  29 }
  30
  31 static inline void
  32 add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l)
  33 {
  34         __add_page_to_lru_list(zone, page, l, &zone->lru[l].list);
  35 }
  36
  37 static inline void
  38 del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list l)
  39 {
  40         list_del(&page->lru);
  41         __dec_zone_state(zone, NR_LRU_BASE + l);
  42         mem_cgroup_del_lru_list(page, l);
  43 }
  44
  45 /**
  46  * page_lru_base_type - which LRU list type should a page be on?
  47  * @page: the page to test
  48  *
  49  * Used for LRU list index arithmetic.
  50  *
  51  * Returns the base LRU type - file or anon - @page should be on.
  52  */
  53 static inline enum lru_list page_lru_base_type(struct page *page)
  54 {
  55         if (page_is_file_cache(page))
  56                 return LRU_INACTIVE_FILE;
  57         return LRU_INACTIVE_ANON;
  58 }
  59
  60 static inline void
  61 del_page_from_lru(struct zone *zone, struct page *page)
  62 {
  63         enum lru_list l;
  64
  65         list_del(&page->lru);
  66         if (PageUnevictable(page)) {
  67                 __ClearPageUnevictable(page);
  68                 l = LRU_UNEVICTABLE;
  69         } else {
  70                 l = page_lru_base_type(page);
  71                 if (PageActive(page)) {
  72                         __ClearPageActive(page);
  73                         l += LRU_ACTIVE;
  74                 }
  75         }
  76         __dec_zone_state(zone, NR_LRU_BASE + l);
  77         mem_cgroup_del_lru_list(page, l);
  78 }
  79
  80 /**
  81  * page_lru - which LRU list should a page be on?
  82  * @page: the page to test
  83  *
  84  * Returns the LRU list a page should be on, as an index
  85  * into the array of LRU lists.
  86  */
  87 static inline enum lru_list page_lru(struct page *page)
  88 {
  89         enum lru_list lru;
  90
  91         if (PageUnevictable(page))
  92                 lru = LRU_UNEVICTABLE;
  93         else {
  94                 lru = page_lru_base_type(page);
  95                 if (PageActive(page))
  96                         lru += LRU_ACTIVE;
  97         }
  98
  99         return lru;
 100 }
 101
 102 #endif