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_CACHE, /* charged as cache */
   8         PCG_USED, /* this object is in use. */
   9         PCG_MIGRATION, /* under page migration */
  10         /* flags for mem_cgroup and file and I/O status */
  11         PCG_MOVE_LOCK, /* For race between move_account v.s. following bits */
  12         PCG_FILE_MAPPED, /* page is accounted as "mapped" */
  13         __NR_PCG_FLAGS,
  14 };
  15
  16 #ifndef __GENERATING_BOUNDS_H
  17 #include <generated/bounds.h>
  18
  19 #ifdef CONFIG_CGROUP_MEM_RES_CTLR
  20 #include <linux/bit_spinlock.h>
  21
  22 /*
  23  * Page Cgroup can be considered as an extended mem_map.
  24  * A page_cgroup page is associated with every page descriptor. The
  25  * page_cgroup helps us identify information about the cgroup
  26  * All page cgroups are allocated at boot or memory hotplug event,
  27  * then the page cgroup for pfn always exists.
  28  */
  29 struct page_cgroup {
  30         unsigned long flags;
  31         struct mem_cgroup *mem_cgroup;
  32 };
  33
  34 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat);
  35
  36 #ifdef CONFIG_SPARSEMEM
  37 static inline void __init page_cgroup_init_flatmem(void)
  38 {
  39 }
  40 extern void __init page_cgroup_init(void);
  41 #else
  42 void __init page_cgroup_init_flatmem(void);
  43 static inline void __init page_cgroup_init(void)
  44 {
  45 }
  46 #endif
  47
  48 struct page_cgroup *lookup_page_cgroup(struct page *page);
  49 struct page *lookup_cgroup_page(struct page_cgroup *pc);
  50
  51 #define TESTPCGFLAG(uname, lname)                       \
  52 static inline int PageCgroup##uname(struct page_cgroup *pc)     \
  53         { return test_bit(PCG_##lname, &pc->flags); }
  54
  55 #define SETPCGFLAG(uname, lname)                        \
  56 static inline void SetPageCgroup##uname(struct page_cgroup *pc)\
  57         { set_bit(PCG_##lname, &pc->flags);  }
  58
  59 #define CLEARPCGFLAG(uname, lname)                      \
  60 static inline void ClearPageCgroup##uname(struct page_cgroup *pc)       \
  61         { clear_bit(PCG_##lname, &pc->flags);  }
  62
  63 #define TESTCLEARPCGFLAG(uname, lname)                  \
  64 static inline int TestClearPageCgroup##uname(struct page_cgroup *pc)    \
  65         { return test_and_clear_bit(PCG_##lname, &pc->flags);  }
  66
  67 /* Cache flag is set only once (at allocation) */
  68 TESTPCGFLAG(Cache, CACHE)
  69 CLEARPCGFLAG(Cache, CACHE)
  70 SETPCGFLAG(Cache, CACHE)
  71
  72 TESTPCGFLAG(Used, USED)
  73 CLEARPCGFLAG(Used, USED)
  74 SETPCGFLAG(Used, USED)
  75
  76 SETPCGFLAG(FileMapped, FILE_MAPPED)
  77 CLEARPCGFLAG(FileMapped, FILE_MAPPED)
  78 TESTPCGFLAG(FileMapped, FILE_MAPPED)
  79
  80 SETPCGFLAG(Migration, MIGRATION)
  81 CLEARPCGFLAG(Migration, MIGRATION)
  82 TESTPCGFLAG(Migration, MIGRATION)
  83
  84 static inline void lock_page_cgroup(struct page_cgroup *pc)
  85 {
  86         /*
  87          * Don't take this lock in IRQ context.
  88          * This lock is for pc->mem_cgroup, USED, CACHE, MIGRATION
  89          */
  90         bit_spin_lock(PCG_LOCK, &pc->flags);
  91 }
  92
  93 static inline void unlock_page_cgroup(struct page_cgroup *pc)
  94 {
  95         bit_spin_unlock(PCG_LOCK, &pc->flags);
  96 }
  97
  98 static inline void move_lock_page_cgroup(struct page_cgroup *pc,
  99         unsigned long *flags)
 100 {
 101         /*
 102          * We know updates to pc->flags of page cache's stats are from both of
 103          * usual context or IRQ context. Disable IRQ to avoid deadlock.
 104          */
 105         local_irq_save(*flags);
 106         bit_spin_lock(PCG_MOVE_LOCK, &pc->flags);
 107 }
 108
 109 static inline void move_unlock_page_cgroup(struct page_cgroup *pc,
 110         unsigned long *flags)
 111 {
 112         bit_spin_unlock(PCG_MOVE_LOCK, &pc->flags);
 113         local_irq_restore(*flags);
 114 }
 115
 116 #else /* CONFIG_CGROUP_MEM_RES_CTLR */
 117 struct page_cgroup;
 118
 119 static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
 120 {
 121 }
 122
 123 static inline struct page_cgroup *lookup_page_cgroup(struct page *page)
 124 {
 125         return NULL;
 126 }
 127
 128 static inline void page_cgroup_init(void)
 129 {
 130 }
 131
 132 static inline void __init page_cgroup_init_flatmem(void)
 133 {
 134 }
 135
 136 #endif /* CONFIG_CGROUP_MEM_RES_CTLR */
 137
 138 #include <linux/swap.h>
 139
 140 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
 141 extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
 142                                         unsigned short old, unsigned short new);
 143 extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
 144 extern unsigned short lookup_swap_cgroup_id(swp_entry_t ent);
 145 extern int swap_cgroup_swapon(int type, unsigned long max_pages);
 146 extern void swap_cgroup_swapoff(int type);
 147 #else
 148
 149 static inline
 150 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
 151 {
 152         return 0;
 153 }
 154
 155 static inline
 156 unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
 157 {
 158         return 0;
 159 }
 160
 161 static inline int
 162 swap_cgroup_swapon(int type, unsigned long max_pages)
 163 {
 164         return 0;
 165 }
 166
 167 static inline void swap_cgroup_swapoff(int type)
 168 {
 169         return;
 170 }
 171
 172 #endif /* CONFIG_CGROUP_MEM_RES_CTLR_SWAP */
 173
 174 #endif /* !__GENERATING_BOUNDS_H */
 175
 176 #endif /* __LINUX_PAGE_CGROUP_H */