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 LRU_FILE 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         if (PageSwapBacked(page))
  20                 return 0;
  21
  22         /* The page is page cache backed by a normal filesystem. */
  23         return LRU_FILE;
  24 }
  25
  26 static inline void
  27 add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l)
  28 {
  29         list_add(&page->lru, &zone->lru[l].list);
  30         __inc_zone_state(zone, NR_LRU_BASE + l);
  31         mem_cgroup_add_lru_list(page, l);
  32 }
  33
  34 static inline void
  35 del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list l)
  36 {
  37         list_del(&page->lru);
  38         __dec_zone_state(zone, NR_LRU_BASE + l);
  39         mem_cgroup_del_lru_list(page, l);
  40 }
  41
  42 static inline void
  43 del_page_from_lru(struct zone *zone, struct page *page)
  44 {
  45         enum lru_list l = LRU_BASE;
  46
  47         list_del(&page->lru);
  48         if (PageUnevictable(page)) {
  49                 __ClearPageUnevictable(page);
  50                 l = LRU_UNEVICTABLE;
  51         } else {
  52                 if (PageActive(page)) {
  53                         __ClearPageActive(page);
  54                         l += LRU_ACTIVE;
  55                 }
  56                 l += page_is_file_cache(page);
  57         }
  58         __dec_zone_state(zone, NR_LRU_BASE + l);
  59         mem_cgroup_del_lru_list(page, l);
  60 }
  61
  62 /**
  63  * page_lru - which LRU list should a page be on?
  64  * @page: the page to test
  65  *
  66  * Returns the LRU list a page should be on, as an index
  67  * into the array of LRU lists.
  68  */
  69 static inline enum lru_list page_lru(struct page *page)
  70 {
  71         enum lru_list lru = LRU_BASE;
  72
  73         if (PageUnevictable(page))
  74                 lru = LRU_UNEVICTABLE;
  75         else {
  76                 if (PageActive(page))
  77                         lru += LRU_ACTIVE;
  78                 lru += page_is_file_cache(page);
  79         }
  80
  81         return lru;
  82 }
  83
  84 #endif