xref: /linux/include/linux/cpuset.h (revision cdb138080b78146d1cdadba9f5dadbeb97445b91)
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/cgroup.h>
15 #include <linux/mm.h>
16 
17 #ifdef CONFIG_CPUSETS
18 
19 extern int number_of_cpusets;	/* How many cpusets are defined in system? */
20 
21 extern int cpuset_init(void);
22 extern void cpuset_init_smp(void);
23 extern void cpuset_update_active_cpus(void);
24 extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
25 extern int cpuset_cpus_allowed_fallback(struct task_struct *p);
26 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
27 #define cpuset_current_mems_allowed (current->mems_allowed)
28 void cpuset_init_current_mems_allowed(void);
29 int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask);
30 
31 extern int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask);
32 extern int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask);
33 
34 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
35 {
36 	return number_of_cpusets <= 1 ||
37 		__cpuset_node_allowed_softwall(node, gfp_mask);
38 }
39 
40 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
41 {
42 	return number_of_cpusets <= 1 ||
43 		__cpuset_node_allowed_hardwall(node, gfp_mask);
44 }
45 
46 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
47 {
48 	return cpuset_node_allowed_softwall(zone_to_nid(z), gfp_mask);
49 }
50 
51 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
52 {
53 	return cpuset_node_allowed_hardwall(zone_to_nid(z), gfp_mask);
54 }
55 
56 extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
57 					  const struct task_struct *tsk2);
58 
59 #define cpuset_memory_pressure_bump() 				\
60 	do {							\
61 		if (cpuset_memory_pressure_enabled)		\
62 			__cpuset_memory_pressure_bump();	\
63 	} while (0)
64 extern int cpuset_memory_pressure_enabled;
65 extern void __cpuset_memory_pressure_bump(void);
66 
67 extern const struct file_operations proc_cpuset_operations;
68 struct seq_file;
69 extern void cpuset_task_status_allowed(struct seq_file *m,
70 					struct task_struct *task);
71 
72 extern int cpuset_mem_spread_node(void);
73 extern int cpuset_slab_spread_node(void);
74 
75 static inline int cpuset_do_page_mem_spread(void)
76 {
77 	return current->flags & PF_SPREAD_PAGE;
78 }
79 
80 static inline int cpuset_do_slab_mem_spread(void)
81 {
82 	return current->flags & PF_SPREAD_SLAB;
83 }
84 
85 extern int current_cpuset_is_being_rebound(void);
86 
87 extern void rebuild_sched_domains(void);
88 
89 extern void cpuset_print_task_mems_allowed(struct task_struct *p);
90 
91 /*
92  * reading current mems_allowed and mempolicy in the fastpath must protected
93  * by get_mems_allowed()
94  */
95 static inline void get_mems_allowed(void)
96 {
97 	current->mems_allowed_change_disable++;
98 
99 	/*
100 	 * ensure that reading mems_allowed and mempolicy happens after the
101 	 * update of ->mems_allowed_change_disable.
102 	 *
103 	 * the write-side task finds ->mems_allowed_change_disable is not 0,
104 	 * and knows the read-side task is reading mems_allowed or mempolicy,
105 	 * so it will clear old bits lazily.
106 	 */
107 	smp_mb();
108 }
109 
110 static inline void put_mems_allowed(void)
111 {
112 	/*
113 	 * ensure that reading mems_allowed and mempolicy before reducing
114 	 * mems_allowed_change_disable.
115 	 *
116 	 * the write-side task will know that the read-side task is still
117 	 * reading mems_allowed or mempolicy, don't clears old bits in the
118 	 * nodemask.
119 	 */
120 	smp_mb();
121 	--ACCESS_ONCE(current->mems_allowed_change_disable);
122 }
123 
124 static inline void set_mems_allowed(nodemask_t nodemask)
125 {
126 	task_lock(current);
127 	current->mems_allowed = nodemask;
128 	task_unlock(current);
129 }
130 
131 #else /* !CONFIG_CPUSETS */
132 
133 static inline int cpuset_init(void) { return 0; }
134 static inline void cpuset_init_smp(void) {}
135 
136 static inline void cpuset_update_active_cpus(void)
137 {
138 	partition_sched_domains(1, NULL, NULL);
139 }
140 
141 static inline void cpuset_cpus_allowed(struct task_struct *p,
142 				       struct cpumask *mask)
143 {
144 	cpumask_copy(mask, cpu_possible_mask);
145 }
146 
147 static inline int cpuset_cpus_allowed_fallback(struct task_struct *p)
148 {
149 	cpumask_copy(&p->cpus_allowed, cpu_possible_mask);
150 	return cpumask_any(cpu_active_mask);
151 }
152 
153 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
154 {
155 	return node_possible_map;
156 }
157 
158 #define cpuset_current_mems_allowed (node_states[N_HIGH_MEMORY])
159 static inline void cpuset_init_current_mems_allowed(void) {}
160 
161 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
162 {
163 	return 1;
164 }
165 
166 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
167 {
168 	return 1;
169 }
170 
171 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
172 {
173 	return 1;
174 }
175 
176 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
177 {
178 	return 1;
179 }
180 
181 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
182 {
183 	return 1;
184 }
185 
186 static inline int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
187 						 const struct task_struct *tsk2)
188 {
189 	return 1;
190 }
191 
192 static inline void cpuset_memory_pressure_bump(void) {}
193 
194 static inline void cpuset_task_status_allowed(struct seq_file *m,
195 						struct task_struct *task)
196 {
197 }
198 
199 static inline int cpuset_mem_spread_node(void)
200 {
201 	return 0;
202 }
203 
204 static inline int cpuset_slab_spread_node(void)
205 {
206 	return 0;
207 }
208 
209 static inline int cpuset_do_page_mem_spread(void)
210 {
211 	return 0;
212 }
213 
214 static inline int cpuset_do_slab_mem_spread(void)
215 {
216 	return 0;
217 }
218 
219 static inline int current_cpuset_is_being_rebound(void)
220 {
221 	return 0;
222 }
223 
224 static inline void rebuild_sched_domains(void)
225 {
226 	partition_sched_domains(1, NULL, NULL);
227 }
228 
229 static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
230 {
231 }
232 
233 static inline void set_mems_allowed(nodemask_t nodemask)
234 {
235 }
236 
237 static inline void get_mems_allowed(void)
238 {
239 }
240 
241 static inline void put_mems_allowed(void)
242 {
243 }
244 
245 #endif /* !CONFIG_CPUSETS */
246 
247 #endif /* _LINUX_CPUSET_H */
248