Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * NUMA memory policies for Linux.
4 * Copyright 2003,2004 Andi Kleen SuSE Labs
5 */
6#ifndef _LINUX_MEMPOLICY_H
7#define _LINUX_MEMPOLICY_H 1
8
9#include <linux/sched.h>
10#include <linux/mmzone.h>
11#include <linux/slab.h>
12#include <linux/rbtree.h>
13#include <linux/spinlock.h>
14#include <linux/nodemask.h>
15#include <linux/pagemap.h>
16#include <uapi/linux/mempolicy.h>
17
18struct mm_struct;
19
20#ifdef CONFIG_NUMA
21
22/*
23 * Describe a memory policy.
24 *
25 * A mempolicy can be either associated with a process or with a VMA.
26 * For VMA related allocations the VMA policy is preferred, otherwise
27 * the process policy is used. Interrupts ignore the memory policy
28 * of the current process.
29 *
30 * Locking policy for interleave:
31 * In process context there is no locking because only the process accesses
32 * its own state. All vma manipulation is somewhat protected by a down_read on
33 * mmap_lock.
34 *
35 * Freeing policy:
36 * Mempolicy objects are reference counted. A mempolicy will be freed when
37 * mpol_put() decrements the reference count to zero.
38 *
39 * Duplicating policy objects:
40 * mpol_dup() allocates a new mempolicy and copies the specified mempolicy
41 * to the new storage. The reference count of the new object is initialized
42 * to 1, representing the caller of mpol_dup().
43 */
44struct mempolicy {
45 atomic_t refcnt;
46 unsigned short mode; /* See MPOL_* above */
47 unsigned short flags; /* See set_mempolicy() MPOL_F_* above */
48 nodemask_t nodes; /* interleave/bind/perfer */
49
50 union {
51 nodemask_t cpuset_mems_allowed; /* relative to these nodes */
52 nodemask_t user_nodemask; /* nodemask passed by user */
53 } w;
54};
55
56/*
57 * Support for managing mempolicy data objects (clone, copy, destroy)
58 * The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
59 */
60
61extern void __mpol_put(struct mempolicy *pol);
62static inline void mpol_put(struct mempolicy *pol)
63{
64 if (pol)
65 __mpol_put(pol);
66}
67
68/*
69 * Does mempolicy pol need explicit unref after use?
70 * Currently only needed for shared policies.
71 */
72static inline int mpol_needs_cond_ref(struct mempolicy *pol)
73{
74 return (pol && (pol->flags & MPOL_F_SHARED));
75}
76
77static inline void mpol_cond_put(struct mempolicy *pol)
78{
79 if (mpol_needs_cond_ref(pol))
80 __mpol_put(pol);
81}
82
83extern struct mempolicy *__mpol_dup(struct mempolicy *pol);
84static inline struct mempolicy *mpol_dup(struct mempolicy *pol)
85{
86 if (pol)
87 pol = __mpol_dup(pol);
88 return pol;
89}
90
91#define vma_policy(vma) ((vma)->vm_policy)
92
93static inline void mpol_get(struct mempolicy *pol)
94{
95 if (pol)
96 atomic_inc(&pol->refcnt);
97}
98
99extern bool __mpol_equal(struct mempolicy *a, struct mempolicy *b);
100static inline bool mpol_equal(struct mempolicy *a, struct mempolicy *b)
101{
102 if (a == b)
103 return true;
104 return __mpol_equal(a, b);
105}
106
107/*
108 * Tree of shared policies for a shared memory region.
109 * Maintain the policies in a pseudo mm that contains vmas. The vmas
110 * carry the policy. As a special twist the pseudo mm is indexed in pages, not
111 * bytes, so that we can work with shared memory segments bigger than
112 * unsigned long.
113 */
114
115struct sp_node {
116 struct rb_node nd;
117 unsigned long start, end;
118 struct mempolicy *policy;
119};
120
121struct shared_policy {
122 struct rb_root root;
123 rwlock_t lock;
124};
125
126int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst);
127void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol);
128int mpol_set_shared_policy(struct shared_policy *info,
129 struct vm_area_struct *vma,
130 struct mempolicy *new);
131void mpol_free_shared_policy(struct shared_policy *p);
132struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
133 unsigned long idx);
134
135struct mempolicy *get_task_policy(struct task_struct *p);
136struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
137 unsigned long addr);
138bool vma_policy_mof(struct vm_area_struct *vma);
139
140extern void numa_default_policy(void);
141extern void numa_policy_init(void);
142extern void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new);
143extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
144
145extern int huge_node(struct vm_area_struct *vma,
146 unsigned long addr, gfp_t gfp_flags,
147 struct mempolicy **mpol, nodemask_t **nodemask);
148extern bool init_nodemask_of_mempolicy(nodemask_t *mask);
149extern bool mempolicy_in_oom_domain(struct task_struct *tsk,
150 const nodemask_t *mask);
151extern nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy);
152
153static inline nodemask_t *policy_nodemask_current(gfp_t gfp)
154{
155 struct mempolicy *mpol = get_task_policy(current);
156
157 return policy_nodemask(gfp, mpol);
158}
159
160extern unsigned int mempolicy_slab_node(void);
161
162extern enum zone_type policy_zone;
163
164static inline void check_highest_zone(enum zone_type k)
165{
166 if (k > policy_zone && k != ZONE_MOVABLE)
167 policy_zone = k;
168}
169
170int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
171 const nodemask_t *to, int flags);
172
173
174#ifdef CONFIG_TMPFS
175extern int mpol_parse_str(char *str, struct mempolicy **mpol);
176#endif
177
178extern void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol);
179
180/* Check if a vma is migratable */
181extern bool vma_migratable(struct vm_area_struct *vma);
182
183extern int mpol_misplaced(struct page *, struct vm_area_struct *, unsigned long);
184extern void mpol_put_task_policy(struct task_struct *);
185
186static inline bool mpol_is_preferred_many(struct mempolicy *pol)
187{
188 return (pol->mode == MPOL_PREFERRED_MANY);
189}
190
191
192#else
193
194struct mempolicy {};
195
196static inline bool mpol_equal(struct mempolicy *a, struct mempolicy *b)
197{
198 return true;
199}
200
201static inline void mpol_put(struct mempolicy *p)
202{
203}
204
205static inline void mpol_cond_put(struct mempolicy *pol)
206{
207}
208
209static inline void mpol_get(struct mempolicy *pol)
210{
211}
212
213struct shared_policy {};
214
215static inline void mpol_shared_policy_init(struct shared_policy *sp,
216 struct mempolicy *mpol)
217{
218}
219
220static inline void mpol_free_shared_policy(struct shared_policy *p)
221{
222}
223
224static inline struct mempolicy *
225mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
226{
227 return NULL;
228}
229
230#define vma_policy(vma) NULL
231
232static inline int
233vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
234{
235 return 0;
236}
237
238static inline void numa_policy_init(void)
239{
240}
241
242static inline void numa_default_policy(void)
243{
244}
245
246static inline void mpol_rebind_task(struct task_struct *tsk,
247 const nodemask_t *new)
248{
249}
250
251static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
252{
253}
254
255static inline int huge_node(struct vm_area_struct *vma,
256 unsigned long addr, gfp_t gfp_flags,
257 struct mempolicy **mpol, nodemask_t **nodemask)
258{
259 *mpol = NULL;
260 *nodemask = NULL;
261 return 0;
262}
263
264static inline bool init_nodemask_of_mempolicy(nodemask_t *m)
265{
266 return false;
267}
268
269static inline int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
270 const nodemask_t *to, int flags)
271{
272 return 0;
273}
274
275static inline void check_highest_zone(int k)
276{
277}
278
279#ifdef CONFIG_TMPFS
280static inline int mpol_parse_str(char *str, struct mempolicy **mpol)
281{
282 return 1; /* error */
283}
284#endif
285
286static inline int mpol_misplaced(struct page *page, struct vm_area_struct *vma,
287 unsigned long address)
288{
289 return -1; /* no node preference */
290}
291
292static inline void mpol_put_task_policy(struct task_struct *task)
293{
294}
295
296static inline nodemask_t *policy_nodemask_current(gfp_t gfp)
297{
298 return NULL;
299}
300
301static inline bool mpol_is_preferred_many(struct mempolicy *pol)
302{
303 return false;
304}
305
306#endif /* CONFIG_NUMA */
307#endif