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 /*
  12  * Both the MPOL_* mempolicy mode and the MPOL_F_* optional mode flags are
  13  * passed by the user to either set_mempolicy() or mbind() in an 'int' actual.
  14  * The MPOL_MODE_FLAGS macro determines the legal set of optional mode flags.
  15  */
  16
  17 /* Policies */
  18 enum {
  19         MPOL_DEFAULT,
  20         MPOL_PREFERRED,
  21         MPOL_BIND,
  22         MPOL_INTERLEAVE,
  23         MPOL_MAX,       /* always last member of enum */
  24 };
  25
  26 /* Flags for set_mempolicy */
  27 #define MPOL_F_STATIC_NODES     (1 << 15)
  28
  29 /*
  30  * MPOL_MODE_FLAGS is the union of all possible optional mode flags passed to
  31  * either set_mempolicy() or mbind().
  32  */
  33 #define MPOL_MODE_FLAGS (MPOL_F_STATIC_NODES)
  34
  35 /* Flags for get_mempolicy */
  36 #define MPOL_F_NODE     (1<<0)  /* return next IL mode instead of node mask */
  37 #define MPOL_F_ADDR     (1<<1)  /* look up vma using address */
  38 #define MPOL_F_MEMS_ALLOWED (1<<2) /* return allowed memories */
  39
  40 /* Flags for mbind */
  41 #define MPOL_MF_STRICT  (1<<0)  /* Verify existing pages in the mapping */
  42 #define MPOL_MF_MOVE    (1<<1)  /* Move pages owned by this process to conform to mapping */
  43 #define MPOL_MF_MOVE_ALL (1<<2) /* Move every page to conform to mapping */
  44 #define MPOL_MF_INTERNAL (1<<3) /* Internal flags start here */
  45
  46 #ifdef __KERNEL__
  47
  48 #include <linux/mmzone.h>
  49 #include <linux/slab.h>
  50 #include <linux/rbtree.h>
  51 #include <linux/spinlock.h>
  52 #include <linux/nodemask.h>
  53
  54 struct vm_area_struct;
  55 struct mm_struct;
  56
  57 #ifdef CONFIG_NUMA
  58
  59 /*
  60  * Describe a memory policy.
  61  *
  62  * A mempolicy can be either associated with a process or with a VMA.
  63  * For VMA related allocations the VMA policy is preferred, otherwise
  64  * the process policy is used. Interrupts ignore the memory policy
  65  * of the current process.
  66  *
  67  * Locking policy for interlave:
  68  * In process context there is no locking because only the process accesses
  69  * its own state. All vma manipulation is somewhat protected by a down_read on
  70  * mmap_sem.
  71  *
  72  * Freeing policy:
  73  * Mempolicy objects are reference counted.  A mempolicy will be freed when
  74  * mpol_free() decrements the reference count to zero.
  75  *
  76  * Copying policy objects:
  77  * mpol_copy() allocates a new mempolicy and copies the specified mempolicy
  78  * to the new storage.  The reference count of the new object is initialized
  79  * to 1, representing the caller of mpol_copy().
  80  */
  81 struct mempolicy {
  82         atomic_t refcnt;
  83         unsigned short policy;  /* See MPOL_* above */
  84         unsigned short flags;   /* See set_mempolicy() MPOL_F_* above */
  85         union {
  86                 short            preferred_node; /* preferred */
  87                 nodemask_t       nodes;         /* interleave/bind */
  88                 /* undefined for default */
  89         } v;
  90         union {
  91                 nodemask_t cpuset_mems_allowed; /* relative to these nodes */
  92                 nodemask_t user_nodemask;       /* nodemask passed by user */
  93         } w;
  94 };
  95
  96 /*
  97  * Support for managing mempolicy data objects (clone, copy, destroy)
  98  * The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
  99  */
 100
 101 extern void __mpol_free(struct mempolicy *pol);
 102 static inline void mpol_free(struct mempolicy *pol)
 103 {
 104         if (pol)
 105                 __mpol_free(pol);
 106 }
 107
 108 extern struct mempolicy *__mpol_copy(struct mempolicy *pol);
 109 static inline struct mempolicy *mpol_copy(struct mempolicy *pol)
 110 {
 111         if (pol)
 112                 pol = __mpol_copy(pol);
 113         return pol;
 114 }
 115
 116 #define vma_policy(vma) ((vma)->vm_policy)
 117 #define vma_set_policy(vma, pol) ((vma)->vm_policy = (pol))
 118
 119 static inline void mpol_get(struct mempolicy *pol)
 120 {
 121         if (pol)
 122                 atomic_inc(&pol->refcnt);
 123 }
 124
 125 extern int __mpol_equal(struct mempolicy *a, struct mempolicy *b);
 126 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 127 {
 128         if (a == b)
 129                 return 1;
 130         return __mpol_equal(a, b);
 131 }
 132
 133 /* Could later add inheritance of the process policy here. */
 134
 135 #define mpol_set_vma_default(vma) ((vma)->vm_policy = NULL)
 136
 137 /*
 138  * Tree of shared policies for a shared memory region.
 139  * Maintain the policies in a pseudo mm that contains vmas. The vmas
 140  * carry the policy. As a special twist the pseudo mm is indexed in pages, not
 141  * bytes, so that we can work with shared memory segments bigger than
 142  * unsigned long.
 143  */
 144
 145 struct sp_node {
 146         struct rb_node nd;
 147         unsigned long start, end;
 148         struct mempolicy *policy;
 149 };
 150
 151 struct shared_policy {
 152         struct rb_root root;
 153         spinlock_t lock;
 154 };
 155
 156 void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
 157                                 unsigned short flags, nodemask_t *nodes);
 158 int mpol_set_shared_policy(struct shared_policy *info,
 159                                 struct vm_area_struct *vma,
 160                                 struct mempolicy *new);
 161 void mpol_free_shared_policy(struct shared_policy *p);
 162 struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
 163                                             unsigned long idx);
 164
 165 extern void numa_default_policy(void);
 166 extern void numa_policy_init(void);
 167 extern void mpol_rebind_task(struct task_struct *tsk,
 168                                         const nodemask_t *new);
 169 extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
 170 extern void mpol_fix_fork_child_flag(struct task_struct *p);
 171
 172 extern struct mempolicy default_policy;
 173 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 174                                 unsigned long addr, gfp_t gfp_flags,
 175                                 struct mempolicy **mpol, nodemask_t **nodemask);
 176 extern unsigned slab_node(struct mempolicy *policy);
 177
 178 extern enum zone_type policy_zone;
 179
 180 static inline void check_highest_zone(enum zone_type k)
 181 {
 182         if (k > policy_zone && k != ZONE_MOVABLE)
 183                 policy_zone = k;
 184 }
 185
 186 int do_migrate_pages(struct mm_struct *mm,
 187         const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
 188
 189 #else
 190
 191 struct mempolicy {};
 192
 193 static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
 194 {
 195         return 1;
 196 }
 197
 198 #define mpol_set_vma_default(vma) do {} while(0)
 199
 200 static inline void mpol_free(struct mempolicy *p)
 201 {
 202 }
 203
 204 static inline void mpol_get(struct mempolicy *pol)
 205 {
 206 }
 207
 208 static inline struct mempolicy *mpol_copy(struct mempolicy *old)
 209 {
 210         return NULL;
 211 }
 212
 213 struct shared_policy {};
 214
 215 static inline int mpol_set_shared_policy(struct shared_policy *info,
 216                                         struct vm_area_struct *vma,
 217                                         struct mempolicy *new)
 218 {
 219         return -EINVAL;
 220 }
 221
 222 static inline void mpol_shared_policy_init(struct shared_policy *info,
 223                 unsigned short policy, unsigned short flags, nodemask_t *nodes)
 224 {
 225 }
 226
 227 static inline void mpol_free_shared_policy(struct shared_policy *p)
 228 {
 229 }
 230
 231 static inline struct mempolicy *
 232 mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
 233 {
 234         return NULL;
 235 }
 236
 237 #define vma_policy(vma) NULL
 238 #define vma_set_policy(vma, pol) do {} while(0)
 239
 240 static inline void numa_policy_init(void)
 241 {
 242 }
 243
 244 static inline void numa_default_policy(void)
 245 {
 246 }
 247
 248 static inline void mpol_rebind_task(struct task_struct *tsk,
 249                                         const nodemask_t *new)
 250 {
 251 }
 252
 253 static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
 254 {
 255 }
 256
 257 static inline void mpol_fix_fork_child_flag(struct task_struct *p)
 258 {
 259 }
 260
 261 static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
 262                                 unsigned long addr, gfp_t gfp_flags,
 263                                 struct mempolicy **mpol, nodemask_t **nodemask)
 264 {
 265         *mpol = NULL;
 266         *nodemask = NULL;
 267         return node_zonelist(0, gfp_flags);
 268 }
 269
 270 static inline int do_migrate_pages(struct mm_struct *mm,
 271                         const nodemask_t *from_nodes,
 272                         const nodemask_t *to_nodes, int flags)
 273 {
 274         return 0;
 275 }
 276
 277 static inline void check_highest_zone(int k)
 278 {
 279 }
 280 #endif /* CONFIG_NUMA */
 281 #endif /* __KERNEL__ */
 282
 283 #endif