include/linux/page_cgroup.h

   1 #ifndef __LINUX_PAGE_CGROUP_H
   2 #define __LINUX_PAGE_CGROUP_H
   3
   4 #ifdef CONFIG_CGROUP_MEM_RES_CTLR
   5 #include <linux/bit_spinlock.h>
   6 /*
   7  * Page Cgroup can be considered as an extended mem_map.
   8  * A page_cgroup page is associated with every page descriptor. The
   9  * page_cgroup helps us identify information about the cgroup
  10  * All page cgroups are allocated at boot or memory hotplug event,
  11  * then the page cgroup for pfn always exists.
  12  */
  13 struct page_cgroup {
  14         unsigned long flags;
  15         struct mem_cgroup *mem_cgroup;
  16         struct page *page;
  17         struct list_head lru;           /* per cgroup LRU list */
  18 };
  19
  20 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat);
  21
  22 #ifdef CONFIG_SPARSEMEM
  23 static inline void __init page_cgroup_init_flatmem(void)
  24 {
  25 }
  26 extern void __init page_cgroup_init(void);
  27 #else
  28 void __init page_cgroup_init_flatmem(void);
  29 static inline void __init page_cgroup_init(void)
  30 {
  31 }
  32 #endif
  33
  34 struct page_cgroup *lookup_page_cgroup(struct page *page);
  35
  36 enum {
  37         /* flags for mem_cgroup */
  38         PCG_LOCK,  /* page cgroup is locked */
  39         PCG_CACHE, /* charged as cache */
  40         PCG_USED, /* this object is in use. */
  41 };
  42
  43 #define TESTPCGFLAG(uname, lname)                       \
  44 static inline int PageCgroup##uname(struct page_cgroup *pc)     \
  45         { return test_bit(PCG_##lname, &pc->flags); }
  46
  47 #define SETPCGFLAG(uname, lname)                        \
  48 static inline void SetPageCgroup##uname(struct page_cgroup *pc)\
  49         { set_bit(PCG_##lname, &pc->flags);  }
  50
  51 #define CLEARPCGFLAG(uname, lname)                      \
  52 static inline void ClearPageCgroup##uname(struct page_cgroup *pc)       \
  53         { clear_bit(PCG_##lname, &pc->flags);  }
  54
  55 /* Cache flag is set only once (at allocation) */
  56 TESTPCGFLAG(Cache, CACHE)
  57
  58 TESTPCGFLAG(Used, USED)
  59 CLEARPCGFLAG(Used, USED)
  60
  61 static inline int page_cgroup_nid(struct page_cgroup *pc)
  62 {
  63         return page_to_nid(pc->page);
  64 }
  65
  66 static inline enum zone_type page_cgroup_zid(struct page_cgroup *pc)
  67 {
  68         return page_zonenum(pc->page);
  69 }
  70
  71 static inline void lock_page_cgroup(struct page_cgroup *pc)
  72 {
  73         bit_spin_lock(PCG_LOCK, &pc->flags);
  74 }
  75
  76 static inline int trylock_page_cgroup(struct page_cgroup *pc)
  77 {
  78         return bit_spin_trylock(PCG_LOCK, &pc->flags);
  79 }
  80
  81 static inline void unlock_page_cgroup(struct page_cgroup *pc)
  82 {
  83         bit_spin_unlock(PCG_LOCK, &pc->flags);
  84 }
  85
  86 #else /* CONFIG_CGROUP_MEM_RES_CTLR */
  87 struct page_cgroup;
  88
  89 static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
  90 {
  91 }
  92
  93 static inline struct page_cgroup *lookup_page_cgroup(struct page *page)
  94 {
  95         return NULL;
  96 }
  97
  98 static inline void page_cgroup_init(void)
  99 {
 100 }
 101
 102 static inline void __init page_cgroup_init_flatmem(void)
 103 {
 104 }
 105
 106 #endif
 107
 108 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
 109 #include <linux/swap.h>
 110 extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
 111 extern unsigned short lookup_swap_cgroup(swp_entry_t ent);
 112 extern int swap_cgroup_swapon(int type, unsigned long max_pages);
 113 extern void swap_cgroup_swapoff(int type);
 114 #else
 115 #include <linux/swap.h>
 116
 117 static inline
 118 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
 119 {
 120         return 0;
 121 }
 122
 123 static inline
 124 unsigned short lookup_swap_cgroup(swp_entry_t ent)
 125 {
 126         return 0;
 127 }
 128
 129 static inline int
 130 swap_cgroup_swapon(int type, unsigned long max_pages)
 131 {
 132         return 0;
 133 }
 134
 135 static inline void swap_cgroup_swapoff(int type)
 136 {
 137         return;
 138 }
 139
 140 #endif
 141 #endif