release/src-rt-6.x.4708/linux/linux-2.6.36/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 {
  25         list_add(&page->lru, &zone->lru[l].list);
  26         __inc_zone_state(zone, NR_LRU_BASE + l);
  27         mem_cgroup_add_lru_list(page, l);
  28 }
  29
  30 static inline void
  31 del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list l)
  32 {
  33         list_del(&page->lru);
  34         __dec_zone_state(zone, NR_LRU_BASE + l);
  35         mem_cgroup_del_lru_list(page, l);
  36 }
  37
  38 /**
  39  * page_lru_base_type - which LRU list type should a page be on?
  40  * @page: the page to test
  41  *
  42  * Used for LRU list index arithmetic.
  43  *
  44  * Returns the base LRU type - file or anon - @page should be on.
  45  */
  46 static inline enum lru_list page_lru_base_type(struct page *page)
  47 {
  48         if (page_is_file_cache(page))
  49                 return LRU_INACTIVE_FILE;
  50         return LRU_INACTIVE_ANON;
  51 }
  52
  53 static inline void
  54 del_page_from_lru(struct zone *zone, struct page *page)
  55 {
  56         enum lru_list l;
  57
  58         list_del(&page->lru);
  59         if (PageUnevictable(page)) {
  60                 __ClearPageUnevictable(page);
  61                 l = LRU_UNEVICTABLE;
  62         } else {
  63                 l = page_lru_base_type(page);
  64                 if (PageActive(page)) {
  65                         __ClearPageActive(page);
  66                         l += LRU_ACTIVE;
  67                 }
  68         }
  69         __dec_zone_state(zone, NR_LRU_BASE + l);
  70         mem_cgroup_del_lru_list(page, l);
  71 }
  72
  73 /**
  74  * page_lru - which LRU list should a page be on?
  75  * @page: the page to test
  76  *
  77  * Returns the LRU list a page should be on, as an index
  78  * into the array of LRU lists.
  79  */
  80 static inline enum lru_list page_lru(struct page *page)
  81 {
  82         enum lru_list lru;
  83
  84         if (PageUnevictable(page))
  85                 lru = LRU_UNEVICTABLE;
  86         else {
  87                 lru = page_lru_base_type(page);
  88                 if (PageActive(page))
  89                         lru += LRU_ACTIVE;
  90         }
  91
  92         return lru;
  93 }
  94
  95 #endif