include/linux/mempolicy.h

   1 #ifndef _LINUX_MEMPOLICY_H
   2 #define _LINUX_MEMPOLICY_H 1
   3
   4 #include <linux/errno.h>
   5
   6 /*
   7  * NUMA memory policies for Linux.
   8  * Copyright 2003,2004 Andi Kleen SuSE Labs
   9  */
  10
  11 /* Policies */
  12 #define MPOL_DEFAULT    0
  13 #define MPOL_PREFERRED  1
  14 #define MPOL_BIND       2
  15 #define MPOL_INTERLEAVE 3
  16
  17 #define MPOL_MAX MPOL_INTERLEAVE
  18
  19 /* Flags for get_mem_policy */
  20 #define MPOL_F_NODE     (1<<0)  /* return next IL mode instead of node mask */
  21 #define MPOL_F_ADDR     (1<<1)  /* look up vma using address */
  22
  23 /* Flags for mbind */
  24 #define MPOL_MF_STRICT  (1<<0)  /* Verify existing pages in the mapping */
  25 #define MPOL_MF_MOVE    (1<<1)  /* Move pages owned by this process to conform to mapping */
  26 #define MPOL_MF_MOVE_ALL (1<<2) /* Move every page to conform to mapping */
  27 #define MPOL_MF_INTERNAL (1<<3) /* Internal flags start here */
  28
  29 #ifdef __KERNEL__
  30
  31 #include <linux/config.h>
  32 #include <linux/mmzone.h>
  33 #include <linux/slab.h>
  34 #include <linux/rbtree.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/nodemask.h>
  37
  38 struct vm_area_struct;
  39
  40 #ifdef CONFIG_NUMA
  41
  42 /*
  43  * Describe a memory policy.
  44  *
  45  * A mempolicy can be either associated with a process or with a VMA.
  46  * For VMA related allocations the VMA policy is preferred, otherwise
  47  * the process policy is used. Interrupts ignore the memory policy
  48  * of the current process.
  49  *
  50  * Locking policy for interlave:
  51  * In process context there is no locking because only the process accesses
  52  * its own state. All vma manipulation is somewhat protected by a down_read on
  53  * mmap_sem.
  54  *
  55  * Freeing policy:
  56  * When policy is MPOL_BIND v.zonelist is kmalloc'ed and must be kfree'd.
  57  * All other policies don't have any external state. mpol_free() handles this.
  58  *
  59  * Copying policy objects:
  60  * For MPOL_BIND the zonelist must be always duplicated. mpol_clone() does this.
  61  */
  62 struct mempolicy {
  63         atomic_t refcnt;
  64         short policy;   /* See MPOL_* above */
  65         union {
  66                 struct zonelist  *zonelist;     /* bind */
  67                 short            preferred_node; /* preferred */
  68                 nodemask_t       nodes;         /* interleave */
  69                 /* undefined for default */
  70         } v;
  71 };
  72
  73 /*
  74  * Support for managing mempolicy data objects (clone, copy, destroy)
  75  * The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
  76  */
  77
  78 extern void __mpol_free(struct mempolicy *pol);
  79 static inline void mpol_free(struct mempolicy *pol)
  80 {
  81         if (pol)
  82                 __mpol_free(pol);
  83 }
  84
  85 extern struct mempolicy *__mpol_copy(struct mempolicy *pol);
  86 static inline struct mempolicy *mpol_copy(struct mempolicy *pol)
  87 {
  88         if (pol)
  89                 pol = __mpol_copy(pol);
  90         return pol;
  91 }
  92
  93 #define vma_policy(vma) ((vma)->vm_policy)
  94 #define vma_set_policy(vma, pol) ((vma)->vm_policy = (pol))
  95
  96 static inline void mpol_get(struct mempolicy *pol)
  97 {
  98         if (pol)
  99                 atomic_inc(&pol->refcnt);
 100 }
 101
 102 extern int __mpol_equal(struct mempolicy *a, struct mempolicy *b);
 103 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 104 {
 105         if (a == b)
 106                 return 1;
 107         return __mpol_equal(a, b);
 108 }
 109 #define vma_mpol_equal(a,b) mpol_equal(vma_policy(a), vma_policy(b))
 110
 111 /* Could later add inheritance of the process policy here. */
 112
 113 #define mpol_set_vma_default(vma) ((vma)->vm_policy = NULL)
 114
 115 /*
 116  * Tree of shared policies for a shared memory region.
 117  * Maintain the policies in a pseudo mm that contains vmas. The vmas
 118  * carry the policy. As a special twist the pseudo mm is indexed in pages, not
 119  * bytes, so that we can work with shared memory segments bigger than
 120  * unsigned long.
 121  */
 122
 123 struct sp_node {
 124         struct rb_node nd;
 125         unsigned long start, end;
 126         struct mempolicy *policy;
 127 };
 128
 129 struct shared_policy {
 130         struct rb_root root;
 131         spinlock_t lock;
 132 };
 133
 134 static inline void mpol_shared_policy_init(struct shared_policy *info)
 135 {
 136         info->root = RB_ROOT;
 137         spin_lock_init(&info->lock);
 138 }
 139
 140 int mpol_set_shared_policy(struct shared_policy *info,
 141                                 struct vm_area_struct *vma,
 142                                 struct mempolicy *new);
 143 void mpol_free_shared_policy(struct shared_policy *p);
 144 struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
 145                                             unsigned long idx);
 146
 147 struct mempolicy *get_vma_policy(struct task_struct *task,
 148                         struct vm_area_struct *vma, unsigned long addr);
 149
 150 extern void numa_default_policy(void);
 151 extern void numa_policy_init(void);
 152 extern void numa_policy_rebind(const nodemask_t *old, const nodemask_t *new);
 153 extern struct mempolicy default_policy;
 154 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 155                 unsigned long addr);
 156
 157 extern int policy_zone;
 158
 159 static inline void check_highest_zone(int k)
 160 {
 161         if (k > policy_zone)
 162                 policy_zone = k;
 163 }
 164
 165 int do_migrate_pages(struct mm_struct *mm,
 166         const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
 167
 168 #else
 169
 170 struct mempolicy {};
 171
 172 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 173 {
 174         return 1;
 175 }
 176 #define vma_mpol_equal(a,b) 1
 177
 178 #define mpol_set_vma_default(vma) do {} while(0)
 179
 180 static inline void mpol_free(struct mempolicy *p)
 181 {
 182 }
 183
 184 static inline void mpol_get(struct mempolicy *pol)
 185 {
 186 }
 187
 188 static inline struct mempolicy *mpol_copy(struct mempolicy *old)
 189 {
 190         return NULL;
 191 }
 192
 193 struct shared_policy {};
 194
 195 static inline int mpol_set_shared_policy(struct shared_policy *info,
 196                                         struct vm_area_struct *vma,
 197                                         struct mempolicy *new)
 198 {
 199         return -EINVAL;
 200 }
 201
 202 static inline void mpol_shared_policy_init(struct shared_policy *info)
 203 {
 204 }
 205
 206 static inline void mpol_free_shared_policy(struct shared_policy *p)
 207 {
 208 }
 209
 210 static inline struct mempolicy *
 211 mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
 212 {
 213         return NULL;
 214 }
 215
 216 #define vma_policy(vma) NULL
 217 #define vma_set_policy(vma, pol) do {} while(0)
 218
 219 static inline void numa_policy_init(void)
 220 {
 221 }
 222
 223 static inline void numa_default_policy(void)
 224 {
 225 }
 226
 227 static inline void numa_policy_rebind(const nodemask_t *old,
 228                                         const nodemask_t *new)
 229 {
 230 }
 231
 232 static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 233                 unsigned long addr)
 234 {
 235         return NODE_DATA(0)->node_zonelists + gfp_zone(GFP_HIGHUSER);
 236 }
 237
 238 static inline int do_migrate_pages(struct mm_struct *mm,
 239                         const nodemask_t *from_nodes,
 240                         const nodemask_t *to_nodes, int flags)
 241 {
 242         return 0;
 243 }
 244
 245 static inline void check_highest_zone(int k)
 246 {
 247 }
 248 #endif /* CONFIG_NUMA */
 249 #endif /* __KERNEL__ */
 250
 251 #endif