include/linux/page_cgroup.h

   1 #ifndef __LINUX_PAGE_CGROUP_H
   2 #define __LINUX_PAGE_CGROUP_H
   3
   4 enum {
   5         /* flags for mem_cgroup */
   6         PCG_LOCK,  /* Lock for pc->mem_cgroup and following bits. */
   7         PCG_USED, /* this object is in use. */
   8         PCG_MIGRATION, /* under page migration */
   9         __NR_PCG_FLAGS,
  10 };
  11
  12 #ifndef __GENERATING_BOUNDS_H
  13 #include <generated/bounds.h>
  14
  15 #ifdef CONFIG_MEMCG
  16 #include <linux/bit_spinlock.h>
  17
  18 /*
  19  * Page Cgroup can be considered as an extended mem_map.
  20  * A page_cgroup page is associated with every page descriptor. The
  21  * page_cgroup helps us identify information about the cgroup
  22  * All page cgroups are allocated at boot or memory hotplug event,
  23  * then the page cgroup for pfn always exists.
  24  */
  25 struct page_cgroup {
  26         unsigned long flags;
  27         struct mem_cgroup *mem_cgroup;
  28 };
  29
  30 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat);
  31
  32 #ifdef CONFIG_SPARSEMEM
  33 static inline void __init page_cgroup_init_flatmem(void)
  34 {
  35 }
  36 extern void __init page_cgroup_init(void);
  37 #else
  38 void __init page_cgroup_init_flatmem(void);
  39 static inline void __init page_cgroup_init(void)
  40 {
  41 }
  42 #endif
  43
  44 struct page_cgroup *lookup_page_cgroup(struct page *page);
  45 struct page *lookup_cgroup_page(struct page_cgroup *pc);
  46
  47 #define TESTPCGFLAG(uname, lname)                       \
  48 static inline int PageCgroup##uname(struct page_cgroup *pc)     \
  49         { return test_bit(PCG_##lname, &pc->flags); }
  50
  51 #define SETPCGFLAG(uname, lname)                        \
  52 static inline void SetPageCgroup##uname(struct page_cgroup *pc)\
  53         { set_bit(PCG_##lname, &pc->flags);  }
  54
  55 #define CLEARPCGFLAG(uname, lname)                      \
  56 static inline void ClearPageCgroup##uname(struct page_cgroup *pc)       \
  57         { clear_bit(PCG_##lname, &pc->flags);  }
  58
  59 #define TESTCLEARPCGFLAG(uname, lname)                  \
  60 static inline int TestClearPageCgroup##uname(struct page_cgroup *pc)    \
  61         { return test_and_clear_bit(PCG_##lname, &pc->flags);  }
  62
  63 TESTPCGFLAG(Used, USED)
  64 CLEARPCGFLAG(Used, USED)
  65 SETPCGFLAG(Used, USED)
  66
  67 SETPCGFLAG(Migration, MIGRATION)
  68 CLEARPCGFLAG(Migration, MIGRATION)
  69 TESTPCGFLAG(Migration, MIGRATION)
  70
  71 static inline void lock_page_cgroup(struct page_cgroup *pc)
  72 {
  73         /*
  74          * Don't take this lock in IRQ context.
  75          * This lock is for pc->mem_cgroup, USED, MIGRATION
  76          */
  77         bit_spin_lock(PCG_LOCK, &pc->flags);
  78 }
  79
  80 static inline void unlock_page_cgroup(struct page_cgroup *pc)
  81 {
  82         bit_spin_unlock(PCG_LOCK, &pc->flags);
  83 }
  84
  85 #else /* CONFIG_MEMCG */
  86 struct page_cgroup;
  87
  88 static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
  89 {
  90 }
  91
  92 static inline struct page_cgroup *lookup_page_cgroup(struct page *page)
  93 {
  94         return NULL;
  95 }
  96
  97 static inline void page_cgroup_init(void)
  98 {
  99 }
 100
 101 static inline void __init page_cgroup_init_flatmem(void)
 102 {
 103 }
 104
 105 #endif /* CONFIG_MEMCG */
 106
 107 #include <linux/swap.h>
 108
 109 #ifdef CONFIG_MEMCG_SWAP
 110 extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
 111                                         unsigned short old, unsigned short new);
 112 extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
 113 extern unsigned short lookup_swap_cgroup_id(swp_entry_t ent);
 114 extern int swap_cgroup_swapon(int type, unsigned long max_pages);
 115 extern void swap_cgroup_swapoff(int type);
 116 #else
 117
 118 static inline
 119 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
 120 {
 121         return 0;
 122 }
 123
 124 static inline
 125 unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
 126 {
 127         return 0;
 128 }
 129
 130 static inline int
 131 swap_cgroup_swapon(int type, unsigned long max_pages)
 132 {
 133         return 0;
 134 }
 135
 136 static inline void swap_cgroup_swapoff(int type)
 137 {
 138         return;
 139 }
 140
 141 #endif /* CONFIG_MEMCG_SWAP */
 142
 143 #endif /* !__GENERATING_BOUNDS_H */
 144
 145 #endif /* __LINUX_PAGE_CGROUP_H */