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
  39 #ifdef CONFIG_NUMA
  40
  41 /*
  42  * Describe a memory policy.
  43  *
  44  * A mempolicy can be either associated with a process or with a VMA.
  45  * For VMA related allocations the VMA policy is preferred, otherwise
  46  * the process policy is used. Interrupts ignore the memory policy
  47  * of the current process.
  48  *
  49  * Locking policy for interlave:
  50  * In process context there is no locking because only the process accesses
  51  * its own state. All vma manipulation is somewhat protected by a down_read on
  52  * mmap_sem.
  53  *
  54  * Freeing policy:
  55  * When policy is MPOL_BIND v.zonelist is kmalloc'ed and must be kfree'd.
  56  * All other policies don't have any external state. mpol_free() handles this.
  57  *
  58  * Copying policy objects:
  59  * For MPOL_BIND the zonelist must be always duplicated. mpol_clone() does this.
  60  */
  61 struct mempolicy {
  62         atomic_t refcnt;
  63         short policy;   /* See MPOL_* above */
  64         union {
  65                 struct zonelist  *zonelist;     /* bind */
  66                 short            preferred_node; /* preferred */
  67                 nodemask_t       nodes;         /* interleave */
  68                 /* undefined for default */
  69         } v;
  70         nodemask_t cpuset_mems_allowed; /* mempolicy relative to these nodes */
  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 void mpol_shared_policy_init(struct shared_policy *info, int policy,
 135                                 nodemask_t *nodes);
 136 int mpol_set_shared_policy(struct shared_policy *info,
 137                                 struct vm_area_struct *vma,
 138                                 struct mempolicy *new);
 139 void mpol_free_shared_policy(struct shared_policy *p);
 140 struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
 141                                             unsigned long idx);
 142
 143 extern void numa_default_policy(void);
 144 extern void numa_policy_init(void);
 145 extern void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *new);
 146 extern void mpol_rebind_task(struct task_struct *tsk,
 147                                         const nodemask_t *new);
 148 extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
 149 extern void mpol_fix_fork_child_flag(struct task_struct *p);
 150 #define set_cpuset_being_rebound(x) (cpuset_being_rebound = (x))
 151
 152 #ifdef CONFIG_CPUSET
 153 #define current_cpuset_is_being_rebound() \
 154                                 (cpuset_being_rebound == current->cpuset)
 155 #else
 156 #define current_cpuset_is_being_rebound() 0
 157 #endif
 158
 159 extern struct mempolicy default_policy;
 160 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 161                 unsigned long addr);
 162 extern unsigned slab_node(struct mempolicy *policy);
 163
 164 extern int policy_zone;
 165
 166 static inline void check_highest_zone(int k)
 167 {
 168         if (k > policy_zone)
 169                 policy_zone = k;
 170 }
 171
 172 int do_migrate_pages(struct mm_struct *mm,
 173         const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
 174
 175 extern void *cpuset_being_rebound;      /* Trigger mpol_copy vma rebind */
 176
 177 #else
 178
 179 struct mempolicy {};
 180
 181 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 182 {
 183         return 1;
 184 }
 185 #define vma_mpol_equal(a,b) 1
 186
 187 #define mpol_set_vma_default(vma) do {} while(0)
 188
 189 static inline void mpol_free(struct mempolicy *p)
 190 {
 191 }
 192
 193 static inline void mpol_get(struct mempolicy *pol)
 194 {
 195 }
 196
 197 static inline struct mempolicy *mpol_copy(struct mempolicy *old)
 198 {
 199         return NULL;
 200 }
 201
 202 struct shared_policy {};
 203
 204 static inline int mpol_set_shared_policy(struct shared_policy *info,
 205                                         struct vm_area_struct *vma,
 206                                         struct mempolicy *new)
 207 {
 208         return -EINVAL;
 209 }
 210
 211 static inline void mpol_shared_policy_init(struct shared_policy *info,
 212                                         int policy, nodemask_t *nodes)
 213 {
 214 }
 215
 216 static inline void mpol_free_shared_policy(struct shared_policy *p)
 217 {
 218 }
 219
 220 static inline struct mempolicy *
 221 mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
 222 {
 223         return NULL;
 224 }
 225
 226 #define vma_policy(vma) NULL
 227 #define vma_set_policy(vma, pol) do {} while(0)
 228
 229 static inline void numa_policy_init(void)
 230 {
 231 }
 232
 233 static inline void numa_default_policy(void)
 234 {
 235 }
 236
 237 static inline void mpol_rebind_policy(struct mempolicy *pol,
 238                                         const nodemask_t *new)
 239 {
 240 }
 241
 242 static inline void mpol_rebind_task(struct task_struct *tsk,
 243                                         const nodemask_t *new)
 244 {
 245 }
 246
 247 static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
 248 {
 249 }
 250
 251 static inline void mpol_fix_fork_child_flag(struct task_struct *p)
 252 {
 253 }
 254
 255 #define set_cpuset_being_rebound(x) do {} while (0)
 256
 257 static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 258                 unsigned long addr)
 259 {
 260         return NODE_DATA(0)->node_zonelists + gfp_zone(GFP_HIGHUSER);
 261 }
 262
 263 static inline int do_migrate_pages(struct mm_struct *mm,
 264                         const nodemask_t *from_nodes,
 265                         const nodemask_t *to_nodes, int flags)
 266 {
 267         return 0;
 268 }
 269
 270 static inline void check_highest_zone(int k)
 271 {
 272 }
 273 #endif /* CONFIG_NUMA */
 274 #endif /* __KERNEL__ */
 275
 276 #endif