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/mmzone.h>
  32 #include <linux/slab.h>
  33 #include <linux/rbtree.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/nodemask.h>
  36
  37 struct vm_area_struct;
  38 struct mm_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         nodemask_t cpuset_mems_allowed; /* mempolicy relative to these nodes */
  72 };
  73
  74 /*
  75  * Support for managing mempolicy data objects (clone, copy, destroy)
  76  * The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
  77  */
  78
  79 extern void __mpol_free(struct mempolicy *pol);
  80 static inline void mpol_free(struct mempolicy *pol)
  81 {
  82         if (pol)
  83                 __mpol_free(pol);
  84 }
  85
  86 extern struct mempolicy *__mpol_copy(struct mempolicy *pol);
  87 static inline struct mempolicy *mpol_copy(struct mempolicy *pol)
  88 {
  89         if (pol)
  90                 pol = __mpol_copy(pol);
  91         return pol;
  92 }
  93
  94 #define vma_policy(vma) ((vma)->vm_policy)
  95 #define vma_set_policy(vma, pol) ((vma)->vm_policy = (pol))
  96
  97 static inline void mpol_get(struct mempolicy *pol)
  98 {
  99         if (pol)
 100                 atomic_inc(&pol->refcnt);
 101 }
 102
 103 extern int __mpol_equal(struct mempolicy *a, struct mempolicy *b);
 104 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 105 {
 106         if (a == b)
 107                 return 1;
 108         return __mpol_equal(a, b);
 109 }
 110 #define vma_mpol_equal(a,b) mpol_equal(vma_policy(a), vma_policy(b))
 111
 112 /* Could later add inheritance of the process policy here. */
 113
 114 #define mpol_set_vma_default(vma) ((vma)->vm_policy = NULL)
 115
 116 /*
 117  * Tree of shared policies for a shared memory region.
 118  * Maintain the policies in a pseudo mm that contains vmas. The vmas
 119  * carry the policy. As a special twist the pseudo mm is indexed in pages, not
 120  * bytes, so that we can work with shared memory segments bigger than
 121  * unsigned long.
 122  */
 123
 124 struct sp_node {
 125         struct rb_node nd;
 126         unsigned long start, end;
 127         struct mempolicy *policy;
 128 };
 129
 130 struct shared_policy {
 131         struct rb_root root;
 132         spinlock_t lock;
 133 };
 134
 135 void mpol_shared_policy_init(struct shared_policy *info, int policy,
 136                                 nodemask_t *nodes);
 137 int mpol_set_shared_policy(struct shared_policy *info,
 138                                 struct vm_area_struct *vma,
 139                                 struct mempolicy *new);
 140 void mpol_free_shared_policy(struct shared_policy *p);
 141 struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
 142                                             unsigned long idx);
 143
 144 extern void numa_default_policy(void);
 145 extern void numa_policy_init(void);
 146 extern void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *new);
 147 extern void mpol_rebind_task(struct task_struct *tsk,
 148                                         const nodemask_t *new);
 149 extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
 150 extern void mpol_fix_fork_child_flag(struct task_struct *p);
 151 #define set_cpuset_being_rebound(x) (cpuset_being_rebound = (x))
 152
 153 #ifdef CONFIG_CPUSET
 154 #define current_cpuset_is_being_rebound() \
 155                                 (cpuset_being_rebound == current->cpuset)
 156 #else
 157 #define current_cpuset_is_being_rebound() 0
 158 #endif
 159
 160 extern struct mempolicy default_policy;
 161 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 162                 unsigned long addr);
 163 extern unsigned slab_node(struct mempolicy *policy);
 164
 165 extern int policy_zone;
 166
 167 static inline void check_highest_zone(int k)
 168 {
 169         if (k > policy_zone)
 170                 policy_zone = k;
 171 }
 172
 173 int do_migrate_pages(struct mm_struct *mm,
 174         const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
 175
 176 extern void *cpuset_being_rebound;      /* Trigger mpol_copy vma rebind */
 177
 178 #else
 179
 180 struct mempolicy {};
 181
 182 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 183 {
 184         return 1;
 185 }
 186 #define vma_mpol_equal(a,b) 1
 187
 188 #define mpol_set_vma_default(vma) do {} while(0)
 189
 190 static inline void mpol_free(struct mempolicy *p)
 191 {
 192 }
 193
 194 static inline void mpol_get(struct mempolicy *pol)
 195 {
 196 }
 197
 198 static inline struct mempolicy *mpol_copy(struct mempolicy *old)
 199 {
 200         return NULL;
 201 }
 202
 203 struct shared_policy {};
 204
 205 static inline int mpol_set_shared_policy(struct shared_policy *info,
 206                                         struct vm_area_struct *vma,
 207                                         struct mempolicy *new)
 208 {
 209         return -EINVAL;
 210 }
 211
 212 static inline void mpol_shared_policy_init(struct shared_policy *info,
 213                                         int policy, nodemask_t *nodes)
 214 {
 215 }
 216
 217 static inline void mpol_free_shared_policy(struct shared_policy *p)
 218 {
 219 }
 220
 221 static inline struct mempolicy *
 222 mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
 223 {
 224         return NULL;
 225 }
 226
 227 #define vma_policy(vma) NULL
 228 #define vma_set_policy(vma, pol) do {} while(0)
 229
 230 static inline void numa_policy_init(void)
 231 {
 232 }
 233
 234 static inline void numa_default_policy(void)
 235 {
 236 }
 237
 238 static inline void mpol_rebind_policy(struct mempolicy *pol,
 239                                         const nodemask_t *new)
 240 {
 241 }
 242
 243 static inline void mpol_rebind_task(struct task_struct *tsk,
 244                                         const nodemask_t *new)
 245 {
 246 }
 247
 248 static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
 249 {
 250 }
 251
 252 static inline void mpol_fix_fork_child_flag(struct task_struct *p)
 253 {
 254 }
 255
 256 #define set_cpuset_being_rebound(x) do {} while (0)
 257
 258 static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 259                 unsigned long addr)
 260 {
 261         return NODE_DATA(0)->node_zonelists + gfp_zone(GFP_HIGHUSER);
 262 }
 263
 264 static inline int do_migrate_pages(struct mm_struct *mm,
 265                         const nodemask_t *from_nodes,
 266                         const nodemask_t *to_nodes, int flags)
 267 {
 268         return 0;
 269 }
 270
 271 static inline void check_highest_zone(int k)
 272 {
 273 }
 274 #endif /* CONFIG_NUMA */
 275 #endif /* __KERNEL__ */
 276
 277 #endif