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,  /* Lock for pc->mem_cgroup and following bits. */
  39         PCG_CACHE, /* charged as cache */
  40         PCG_USED, /* this object is in use. */
  41         PCG_MIGRATION, /* under page migration */
  42         /* flags for mem_cgroup and file and I/O status */
  43         PCG_MOVE_LOCK, /* For race between move_account v.s. following bits */
  44         PCG_FILE_MAPPED, /* page is accounted as "mapped" */
  45         /* No lock in page_cgroup */
  46         PCG_ACCT_LRU, /* page has been accounted for (under lru_lock) */
  47 };
  48
  49 #define TESTPCGFLAG(uname, lname)                       \
  50 static inline int PageCgroup##uname(struct page_cgroup *pc)     \
  51         { return test_bit(PCG_##lname, &pc->flags); }
  52
  53 #define SETPCGFLAG(uname, lname)                        \
  54 static inline void SetPageCgroup##uname(struct page_cgroup *pc)\
  55         { set_bit(PCG_##lname, &pc->flags);  }
  56
  57 #define CLEARPCGFLAG(uname, lname)                      \
  58 static inline void ClearPageCgroup##uname(struct page_cgroup *pc)       \
  59         { clear_bit(PCG_##lname, &pc->flags);  }
  60
  61 #define TESTCLEARPCGFLAG(uname, lname)                  \
  62 static inline int TestClearPageCgroup##uname(struct page_cgroup *pc)    \
  63         { return test_and_clear_bit(PCG_##lname, &pc->flags);  }
  64
  65 /* Cache flag is set only once (at allocation) */
  66 TESTPCGFLAG(Cache, CACHE)
  67 CLEARPCGFLAG(Cache, CACHE)
  68 SETPCGFLAG(Cache, CACHE)
  69
  70 TESTPCGFLAG(Used, USED)
  71 CLEARPCGFLAG(Used, USED)
  72 SETPCGFLAG(Used, USED)
  73
  74 SETPCGFLAG(AcctLRU, ACCT_LRU)
  75 CLEARPCGFLAG(AcctLRU, ACCT_LRU)
  76 TESTPCGFLAG(AcctLRU, ACCT_LRU)
  77 TESTCLEARPCGFLAG(AcctLRU, ACCT_LRU)
  78
  79
  80 SETPCGFLAG(FileMapped, FILE_MAPPED)
  81 CLEARPCGFLAG(FileMapped, FILE_MAPPED)
  82 TESTPCGFLAG(FileMapped, FILE_MAPPED)
  83
  84 SETPCGFLAG(Migration, MIGRATION)
  85 CLEARPCGFLAG(Migration, MIGRATION)
  86 TESTPCGFLAG(Migration, MIGRATION)
  87
  88 static inline int page_cgroup_nid(struct page_cgroup *pc)
  89 {
  90         return page_to_nid(pc->page);
  91 }
  92
  93 static inline enum zone_type page_cgroup_zid(struct page_cgroup *pc)
  94 {
  95         return page_zonenum(pc->page);
  96 }
  97
  98 static inline void lock_page_cgroup(struct page_cgroup *pc)
  99 {
 100         /*
 101          * Don't take this lock in IRQ context.
 102          * This lock is for pc->mem_cgroup, USED, CACHE, MIGRATION
 103          */
 104         bit_spin_lock(PCG_LOCK, &pc->flags);
 105 }
 106
 107 static inline void unlock_page_cgroup(struct page_cgroup *pc)
 108 {
 109         bit_spin_unlock(PCG_LOCK, &pc->flags);
 110 }
 111
 112 static inline int page_is_cgroup_locked(struct page_cgroup *pc)
 113 {
 114         return bit_spin_is_locked(PCG_LOCK, &pc->flags);
 115 }
 116
 117 static inline void move_lock_page_cgroup(struct page_cgroup *pc,
 118         unsigned long *flags)
 119 {
 120         /*
 121          * We know updates to pc->flags of page cache's stats are from both of
 122          * usual context or IRQ context. Disable IRQ to avoid deadlock.
 123          */
 124         local_irq_save(*flags);
 125         bit_spin_lock(PCG_MOVE_LOCK, &pc->flags);
 126 }
 127
 128 static inline void move_unlock_page_cgroup(struct page_cgroup *pc,
 129         unsigned long *flags)
 130 {
 131         bit_spin_unlock(PCG_MOVE_LOCK, &pc->flags);
 132         local_irq_restore(*flags);
 133 }
 134
 135 #else /* CONFIG_CGROUP_MEM_RES_CTLR */
 136 struct page_cgroup;
 137
 138 static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
 139 {
 140 }
 141
 142 static inline struct page_cgroup *lookup_page_cgroup(struct page *page)
 143 {
 144         return NULL;
 145 }
 146
 147 static inline void page_cgroup_init(void)
 148 {
 149 }
 150
 151 static inline void __init page_cgroup_init_flatmem(void)
 152 {
 153 }
 154
 155 #endif
 156
 157 #include <linux/swap.h>
 158
 159 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
 160 extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
 161                                         unsigned short old, unsigned short new);
 162 extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
 163 extern unsigned short lookup_swap_cgroup(swp_entry_t ent);
 164 extern int swap_cgroup_swapon(int type, unsigned long max_pages);
 165 extern void swap_cgroup_swapoff(int type);
 166 #else
 167
 168 static inline
 169 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
 170 {
 171         return 0;
 172 }
 173
 174 static inline
 175 unsigned short lookup_swap_cgroup(swp_entry_t ent)
 176 {
 177         return 0;
 178 }
 179
 180 static inline int
 181 swap_cgroup_swapon(int type, unsigned long max_pages)
 182 {
 183         return 0;
 184 }
 185
 186 static inline void swap_cgroup_swapoff(int type)
 187 {
 188         return;
 189 }
 190
 191 #endif
 192 #endif