xref: /linux-6.15/include/linux/cpuset.h (revision e756bc56)
1 #ifndef _LINUX_CPUSET_H
2 #define _LINUX_CPUSET_H
3 /*
4  *  cpuset interface
5  *
6  *  Copyright (C) 2003 BULL SA
7  *  Copyright (C) 2004-2006 Silicon Graphics, Inc.
8  *
9  */
10 
11 #include <linux/sched.h>
12 #include <linux/cpumask.h>
13 #include <linux/nodemask.h>
14 #include <linux/mm.h>
15 
16 #ifdef CONFIG_CPUSETS
17 
18 extern int number_of_cpusets;	/* How many cpusets are defined in system? */
19 
20 extern int cpuset_init(void);
21 extern void cpuset_init_smp(void);
22 extern void cpuset_update_active_cpus(bool cpu_online);
23 extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
24 extern void cpuset_cpus_allowed_fallback(struct task_struct *p);
25 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
26 #define cpuset_current_mems_allowed (current->mems_allowed)
27 void cpuset_init_current_mems_allowed(void);
28 int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask);
29 
30 extern int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask);
31 extern int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask);
32 
33 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
34 {
35 	return number_of_cpusets <= 1 ||
36 		__cpuset_node_allowed_softwall(node, gfp_mask);
37 }
38 
39 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
40 {
41 	return number_of_cpusets <= 1 ||
42 		__cpuset_node_allowed_hardwall(node, gfp_mask);
43 }
44 
45 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
46 {
47 	return cpuset_node_allowed_softwall(zone_to_nid(z), gfp_mask);
48 }
49 
50 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
51 {
52 	return cpuset_node_allowed_hardwall(zone_to_nid(z), gfp_mask);
53 }
54 
55 extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
56 					  const struct task_struct *tsk2);
57 
58 #define cpuset_memory_pressure_bump() 				\
59 	do {							\
60 		if (cpuset_memory_pressure_enabled)		\
61 			__cpuset_memory_pressure_bump();	\
62 	} while (0)
63 extern int cpuset_memory_pressure_enabled;
64 extern void __cpuset_memory_pressure_bump(void);
65 
66 extern void cpuset_task_status_allowed(struct seq_file *m,
67 					struct task_struct *task);
68 extern int proc_cpuset_show(struct seq_file *, void *);
69 
70 extern int cpuset_mem_spread_node(void);
71 extern int cpuset_slab_spread_node(void);
72 
73 static inline int cpuset_do_page_mem_spread(void)
74 {
75 	return current->flags & PF_SPREAD_PAGE;
76 }
77 
78 static inline int cpuset_do_slab_mem_spread(void)
79 {
80 	return current->flags & PF_SPREAD_SLAB;
81 }
82 
83 extern int current_cpuset_is_being_rebound(void);
84 
85 extern void rebuild_sched_domains(void);
86 
87 extern void cpuset_print_task_mems_allowed(struct task_struct *p);
88 
89 /*
90  * get_mems_allowed is required when making decisions involving mems_allowed
91  * such as during page allocation. mems_allowed can be updated in parallel
92  * and depending on the new value an operation can fail potentially causing
93  * process failure. A retry loop with get_mems_allowed and put_mems_allowed
94  * prevents these artificial failures.
95  */
96 static inline unsigned int get_mems_allowed(void)
97 {
98 	return read_seqcount_begin(&current->mems_allowed_seq);
99 }
100 
101 /*
102  * If this returns false, the operation that took place after get_mems_allowed
103  * may have failed. It is up to the caller to retry the operation if
104  * appropriate.
105  */
106 static inline bool put_mems_allowed(unsigned int seq)
107 {
108 	return !read_seqcount_retry(&current->mems_allowed_seq, seq);
109 }
110 
111 static inline void set_mems_allowed(nodemask_t nodemask)
112 {
113 	unsigned long flags;
114 
115 	task_lock(current);
116 	local_irq_save(flags);
117 	write_seqcount_begin(&current->mems_allowed_seq);
118 	current->mems_allowed = nodemask;
119 	write_seqcount_end(&current->mems_allowed_seq);
120 	local_irq_restore(flags);
121 	task_unlock(current);
122 }
123 
124 #else /* !CONFIG_CPUSETS */
125 
126 static inline int cpuset_init(void) { return 0; }
127 static inline void cpuset_init_smp(void) {}
128 
129 static inline void cpuset_update_active_cpus(bool cpu_online)
130 {
131 	partition_sched_domains(1, NULL, NULL);
132 }
133 
134 static inline void cpuset_cpus_allowed(struct task_struct *p,
135 				       struct cpumask *mask)
136 {
137 	cpumask_copy(mask, cpu_possible_mask);
138 }
139 
140 static inline void cpuset_cpus_allowed_fallback(struct task_struct *p)
141 {
142 }
143 
144 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
145 {
146 	return node_possible_map;
147 }
148 
149 #define cpuset_current_mems_allowed (node_states[N_MEMORY])
150 static inline void cpuset_init_current_mems_allowed(void) {}
151 
152 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
153 {
154 	return 1;
155 }
156 
157 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
158 {
159 	return 1;
160 }
161 
162 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
163 {
164 	return 1;
165 }
166 
167 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
168 {
169 	return 1;
170 }
171 
172 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
173 {
174 	return 1;
175 }
176 
177 static inline int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
178 						 const struct task_struct *tsk2)
179 {
180 	return 1;
181 }
182 
183 static inline void cpuset_memory_pressure_bump(void) {}
184 
185 static inline void cpuset_task_status_allowed(struct seq_file *m,
186 						struct task_struct *task)
187 {
188 }
189 
190 static inline int cpuset_mem_spread_node(void)
191 {
192 	return 0;
193 }
194 
195 static inline int cpuset_slab_spread_node(void)
196 {
197 	return 0;
198 }
199 
200 static inline int cpuset_do_page_mem_spread(void)
201 {
202 	return 0;
203 }
204 
205 static inline int cpuset_do_slab_mem_spread(void)
206 {
207 	return 0;
208 }
209 
210 static inline int current_cpuset_is_being_rebound(void)
211 {
212 	return 0;
213 }
214 
215 static inline void rebuild_sched_domains(void)
216 {
217 	partition_sched_domains(1, NULL, NULL);
218 }
219 
220 static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
221 {
222 }
223 
224 static inline void set_mems_allowed(nodemask_t nodemask)
225 {
226 }
227 
228 static inline unsigned int get_mems_allowed(void)
229 {
230 	return 0;
231 }
232 
233 static inline bool put_mems_allowed(unsigned int seq)
234 {
235 	return true;
236 }
237 
238 #endif /* !CONFIG_CPUSETS */
239 
240 #endif /* _LINUX_CPUSET_H */
241