include/linux/mm_inline.h

   1 #ifndef LINUX_MM_INLINE_H
   2 #define LINUX_MM_INLINE_H
   3
   4 #include <linux/huge_mm.h>
   5 #include <linux/swap.h>
   6
   7 /**
   8  * page_is_file_cache - should the page be on a file LRU or anon LRU?
   9  * @page: the page to test
  10  *
  11  * Returns 1 if @page is page cache page backed by a regular filesystem,
  12  * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed.
  13  * Used by functions that manipulate the LRU lists, to sort a page
  14  * onto the right LRU list.
  15  *
  16  * We would like to get this info without a page flag, but the state
  17  * needs to survive until the page is last deleted from the LRU, which
  18  * could be as far down as __page_cache_release.
  19  */
  20 static inline int page_is_file_cache(struct page *page)
  21 {
  22         return !PageSwapBacked(page);
  23 }
  24
  25 static __always_inline void __update_lru_size(struct lruvec *lruvec,
  26                                 enum lru_list lru, enum zone_type zid,
  27                                 int nr_pages)
  28 {
  29         struct pglist_data *pgdat = lruvec_pgdat(lruvec);
  30
  31         __mod_node_page_state(pgdat, NR_LRU_BASE + lru, nr_pages);
  32         __mod_zone_page_state(&pgdat->node_zones[zid],
  33                 NR_ZONE_LRU_BASE + !!is_file_lru(lru),
  34                 nr_pages);
  35 }
  36
  37 static __always_inline void update_lru_size(struct lruvec *lruvec,
  38                                 enum lru_list lru, enum zone_type zid,
  39                                 int nr_pages)
  40 {
  41 #ifdef CONFIG_MEMCG
  42         mem_cgroup_update_lru_size(lruvec, lru, zid, nr_pages);
  43 #else
  44         __update_lru_size(lruvec, lru, zid, nr_pages);
  45 #endif
  46 }
  47
  48 static __always_inline void add_page_to_lru_list(struct page *page,
  49                                 struct lruvec *lruvec, enum lru_list lru)
  50 {
  51         update_lru_size(lruvec, lru, page_zonenum(page), hpage_nr_pages(page));
  52         list_add(&page->lru, &lruvec->lists[lru]);
  53 }
  54
  55 static __always_inline void del_page_from_lru_list(struct page *page,
  56                                 struct lruvec *lruvec, enum lru_list lru)
  57 {
  58         list_del(&page->lru);
  59         update_lru_size(lruvec, lru, page_zonenum(page), -hpage_nr_pages(page));
  60 }
  61
  62 /**
  63  * page_lru_base_type - which LRU list type should a page be on?
  64  * @page: the page to test
  65  *
  66  * Used for LRU list index arithmetic.
  67  *
  68  * Returns the base LRU type - file or anon - @page should be on.
  69  */
  70 static inline enum lru_list page_lru_base_type(struct page *page)
  71 {
  72         if (page_is_file_cache(page))
  73                 return LRU_INACTIVE_FILE;
  74         return LRU_INACTIVE_ANON;
  75 }
  76
  77 /**
  78  * page_off_lru - which LRU list was page on? clearing its lru flags.
  79  * @page: the page to test
  80  *
  81  * Returns the LRU list a page was on, as an index into the array of LRU
  82  * lists; and clears its Unevictable or Active flags, ready for freeing.
  83  */
  84 static __always_inline enum lru_list page_off_lru(struct page *page)
  85 {
  86         enum lru_list lru;
  87
  88         if (PageUnevictable(page)) {
  89                 __ClearPageUnevictable(page);
  90                 lru = LRU_UNEVICTABLE;
  91         } else {
  92                 lru = page_lru_base_type(page);
  93                 if (PageActive(page)) {
  94                         __ClearPageActive(page);
  95                         lru += LRU_ACTIVE;
  96                 }
  97         }
  98         return lru;
  99 }
 100
 101 /**
 102  * page_lru - which LRU list should a page be on?
 103  * @page: the page to test
 104  *
 105  * Returns the LRU list a page should be on, as an index
 106  * into the array of LRU lists.
 107  */
 108 static __always_inline enum lru_list page_lru(struct page *page)
 109 {
 110         enum lru_list lru;
 111
 112         if (PageUnevictable(page))
 113                 lru = LRU_UNEVICTABLE;
 114         else {
 115                 lru = page_lru_base_type(page);
 116                 if (PageActive(page))
 117                         lru += LRU_ACTIVE;
 118         }
 119         return lru;
 120 }
 121
 122 #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
 123
 124 #endif