| 1 | /* |
| 2 | * NUMA memory policies for Linux. |
| 3 | * Copyright 2003,2004 Andi Kleen SuSE Labs |
| 4 | */ |
| 5 | #ifndef _LINUX_MEMPOLICY_H |
| 6 | #define _LINUX_MEMPOLICY_H 1 |
| 7 | |
| 8 | |
| 9 | #include <linux/mmzone.h> |
| 10 | #include <linux/slab.h> |
| 11 | #include <linux/rbtree.h> |
| 12 | #include <linux/spinlock.h> |
| 13 | #include <linux/nodemask.h> |
| 14 | #include <linux/pagemap.h> |
| 15 | #include <uapi/linux/mempolicy.h> |
| 16 | |
| 17 | struct mm_struct; |
| 18 | |
| 19 | #ifdef CONFIG_NUMA |
| 20 | |
| 21 | /* |
| 22 | * Describe a memory policy. |
| 23 | * |
| 24 | * A mempolicy can be either associated with a process or with a VMA. |
| 25 | * For VMA related allocations the VMA policy is preferred, otherwise |
| 26 | * the process policy is used. Interrupts ignore the memory policy |
| 27 | * of the current process. |
| 28 | * |
| 29 | * Locking policy for interlave: |
| 30 | * In process context there is no locking because only the process accesses |
| 31 | * its own state. All vma manipulation is somewhat protected by a down_read on |
| 32 | * mmap_sem. |
| 33 | * |
| 34 | * Freeing policy: |
| 35 | * Mempolicy objects are reference counted. A mempolicy will be freed when |
| 36 | * mpol_put() decrements the reference count to zero. |
| 37 | * |
| 38 | * Duplicating policy objects: |
| 39 | * mpol_dup() allocates a new mempolicy and copies the specified mempolicy |
| 40 | * to the new storage. The reference count of the new object is initialized |
| 41 | * to 1, representing the caller of mpol_dup(). |
| 42 | */ |
| 43 | struct mempolicy { |
| 44 | atomic_t refcnt; |
| 45 | unsigned short mode; /* See MPOL_* above */ |
| 46 | unsigned short flags; /* See set_mempolicy() MPOL_F_* above */ |
| 47 | union { |
| 48 | short preferred_node; /* preferred */ |
| 49 | nodemask_t nodes; /* interleave/bind */ |
| 50 | /* undefined for default */ |
| 51 | } v; |
| 52 | union { |
| 53 | nodemask_t cpuset_mems_allowed; /* relative to these nodes */ |
| 54 | nodemask_t user_nodemask; /* nodemask passed by user */ |
| 55 | } w; |
| 56 | }; |
| 57 | |
| 58 | /* |
| 59 | * Support for managing mempolicy data objects (clone, copy, destroy) |
| 60 | * The default fast path of a NULL MPOL_DEFAULT policy is always inlined. |
| 61 | */ |
| 62 | |
| 63 | extern void __mpol_put(struct mempolicy *pol); |
| 64 | static inline void mpol_put(struct mempolicy *pol) |
| 65 | { |
| 66 | if (pol) |
| 67 | __mpol_put(pol); |
| 68 | } |
| 69 | |
| 70 | /* |
| 71 | * Does mempolicy pol need explicit unref after use? |
| 72 | * Currently only needed for shared policies. |
| 73 | */ |
| 74 | static inline int mpol_needs_cond_ref(struct mempolicy *pol) |
| 75 | { |
| 76 | return (pol && (pol->flags & MPOL_F_SHARED)); |
| 77 | } |
| 78 | |
| 79 | static inline void mpol_cond_put(struct mempolicy *pol) |
| 80 | { |
| 81 | if (mpol_needs_cond_ref(pol)) |
| 82 | __mpol_put(pol); |
| 83 | } |
| 84 | |
| 85 | extern struct mempolicy *__mpol_dup(struct mempolicy *pol); |
| 86 | static inline struct mempolicy *mpol_dup(struct mempolicy *pol) |
| 87 | { |
| 88 | if (pol) |
| 89 | pol = __mpol_dup(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 bool __mpol_equal(struct mempolicy *a, struct mempolicy *b); |
| 103 | static inline bool mpol_equal(struct mempolicy *a, struct mempolicy *b) |
| 104 | { |
| 105 | if (a == b) |
| 106 | return true; |
| 107 | return __mpol_equal(a, b); |
| 108 | } |
| 109 | |
| 110 | /* |
| 111 | * Tree of shared policies for a shared memory region. |
| 112 | * Maintain the policies in a pseudo mm that contains vmas. The vmas |
| 113 | * carry the policy. As a special twist the pseudo mm is indexed in pages, not |
| 114 | * bytes, so that we can work with shared memory segments bigger than |
| 115 | * unsigned long. |
| 116 | */ |
| 117 | |
| 118 | struct sp_node { |
| 119 | struct rb_node nd; |
| 120 | unsigned long start, end; |
| 121 | struct mempolicy *policy; |
| 122 | }; |
| 123 | |
| 124 | struct shared_policy { |
| 125 | struct rb_root root; |
| 126 | spinlock_t lock; |
| 127 | }; |
| 128 | |
| 129 | void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol); |
| 130 | int mpol_set_shared_policy(struct shared_policy *info, |
| 131 | struct vm_area_struct *vma, |
| 132 | struct mempolicy *new); |
| 133 | void mpol_free_shared_policy(struct shared_policy *p); |
| 134 | struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp, |
| 135 | unsigned long idx); |
| 136 | |
| 137 | struct mempolicy *get_vma_policy(struct task_struct *tsk, |
| 138 | struct vm_area_struct *vma, unsigned long addr); |
| 139 | |
| 140 | extern void numa_default_policy(void); |
| 141 | extern void numa_policy_init(void); |
| 142 | extern void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new, |
| 143 | enum mpol_rebind_step step); |
| 144 | extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new); |
| 145 | extern void mpol_fix_fork_child_flag(struct task_struct *p); |
| 146 | |
| 147 | extern struct zonelist *huge_zonelist(struct vm_area_struct *vma, |
| 148 | unsigned long addr, gfp_t gfp_flags, |
| 149 | struct mempolicy **mpol, nodemask_t **nodemask); |
| 150 | extern bool init_nodemask_of_mempolicy(nodemask_t *mask); |
| 151 | extern bool mempolicy_nodemask_intersects(struct task_struct *tsk, |
| 152 | const nodemask_t *mask); |
| 153 | extern unsigned slab_node(void); |
| 154 | |
| 155 | extern enum zone_type policy_zone; |
| 156 | |
| 157 | static inline void check_highest_zone(enum zone_type k) |
| 158 | { |
| 159 | if (k > policy_zone && k != ZONE_MOVABLE) |
| 160 | policy_zone = k; |
| 161 | } |
| 162 | |
| 163 | int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
| 164 | const nodemask_t *to, int flags); |
| 165 | |
| 166 | |
| 167 | #ifdef CONFIG_TMPFS |
| 168 | extern int mpol_parse_str(char *str, struct mempolicy **mpol); |
| 169 | #endif |
| 170 | |
| 171 | extern int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol); |
| 172 | |
| 173 | /* Check if a vma is migratable */ |
| 174 | static inline int vma_migratable(struct vm_area_struct *vma) |
| 175 | { |
| 176 | if (vma->vm_flags & (VM_IO | VM_HUGETLB | VM_PFNMAP)) |
| 177 | return 0; |
| 178 | /* |
| 179 | * Migration allocates pages in the highest zone. If we cannot |
| 180 | * do so then migration (at least from node to node) is not |
| 181 | * possible. |
| 182 | */ |
| 183 | if (vma->vm_file && |
| 184 | gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping)) |
| 185 | < policy_zone) |
| 186 | return 0; |
| 187 | return 1; |
| 188 | } |
| 189 | |
| 190 | extern int mpol_misplaced(struct page *, struct vm_area_struct *, unsigned long); |
| 191 | |
| 192 | #else |
| 193 | |
| 194 | struct mempolicy {}; |
| 195 | |
| 196 | static inline bool mpol_equal(struct mempolicy *a, struct mempolicy *b) |
| 197 | { |
| 198 | return true; |
| 199 | } |
| 200 | |
| 201 | static inline void mpol_put(struct mempolicy *p) |
| 202 | { |
| 203 | } |
| 204 | |
| 205 | static inline void mpol_cond_put(struct mempolicy *pol) |
| 206 | { |
| 207 | } |
| 208 | |
| 209 | static inline void mpol_get(struct mempolicy *pol) |
| 210 | { |
| 211 | } |
| 212 | |
| 213 | static inline struct mempolicy *mpol_dup(struct mempolicy *old) |
| 214 | { |
| 215 | return NULL; |
| 216 | } |
| 217 | |
| 218 | struct shared_policy {}; |
| 219 | |
| 220 | static inline int mpol_set_shared_policy(struct shared_policy *info, |
| 221 | struct vm_area_struct *vma, |
| 222 | struct mempolicy *new) |
| 223 | { |
| 224 | return -EINVAL; |
| 225 | } |
| 226 | |
| 227 | static inline void mpol_shared_policy_init(struct shared_policy *sp, |
| 228 | struct mempolicy *mpol) |
| 229 | { |
| 230 | } |
| 231 | |
| 232 | static inline void mpol_free_shared_policy(struct shared_policy *p) |
| 233 | { |
| 234 | } |
| 235 | |
| 236 | static inline struct mempolicy * |
| 237 | mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx) |
| 238 | { |
| 239 | return NULL; |
| 240 | } |
| 241 | |
| 242 | #define vma_policy(vma) NULL |
| 243 | #define vma_set_policy(vma, pol) do {} while(0) |
| 244 | |
| 245 | static inline void numa_policy_init(void) |
| 246 | { |
| 247 | } |
| 248 | |
| 249 | static inline void numa_default_policy(void) |
| 250 | { |
| 251 | } |
| 252 | |
| 253 | static inline void mpol_rebind_task(struct task_struct *tsk, |
| 254 | const nodemask_t *new, |
| 255 | enum mpol_rebind_step step) |
| 256 | { |
| 257 | } |
| 258 | |
| 259 | static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) |
| 260 | { |
| 261 | } |
| 262 | |
| 263 | static inline void mpol_fix_fork_child_flag(struct task_struct *p) |
| 264 | { |
| 265 | } |
| 266 | |
| 267 | static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma, |
| 268 | unsigned long addr, gfp_t gfp_flags, |
| 269 | struct mempolicy **mpol, nodemask_t **nodemask) |
| 270 | { |
| 271 | *mpol = NULL; |
| 272 | *nodemask = NULL; |
| 273 | return node_zonelist(0, gfp_flags); |
| 274 | } |
| 275 | |
| 276 | static inline bool init_nodemask_of_mempolicy(nodemask_t *m) |
| 277 | { |
| 278 | return false; |
| 279 | } |
| 280 | |
| 281 | static inline bool mempolicy_nodemask_intersects(struct task_struct *tsk, |
| 282 | const nodemask_t *mask) |
| 283 | { |
| 284 | return false; |
| 285 | } |
| 286 | |
| 287 | static inline int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
| 288 | const nodemask_t *to, int flags) |
| 289 | { |
| 290 | return 0; |
| 291 | } |
| 292 | |
| 293 | static inline void check_highest_zone(int k) |
| 294 | { |
| 295 | } |
| 296 | |
| 297 | #ifdef CONFIG_TMPFS |
| 298 | static inline int mpol_parse_str(char *str, struct mempolicy **mpol) |
| 299 | { |
| 300 | return 1; /* error */ |
| 301 | } |
| 302 | #endif |
| 303 | |
| 304 | static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol) |
| 305 | { |
| 306 | return 0; |
| 307 | } |
| 308 | |
| 309 | static inline int mpol_misplaced(struct page *page, struct vm_area_struct *vma, |
| 310 | unsigned long address) |
| 311 | { |
| 312 | return -1; /* no node preference */ |
| 313 | } |
| 314 | |
| 315 | #endif /* CONFIG_NUMA */ |
| 316 | #endif |