include/linux/cpuset.h

   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 void 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  * get_mems_allowed is required when making decisions involving mems_allowed
  93  * such as during page allocation. mems_allowed can be updated in parallel
  94  * and depending on the new value an operation can fail potentially causing
  95  * process failure. A retry loop with get_mems_allowed and put_mems_allowed
  96  * prevents these artificial failures.
  97  */
  98 static inline unsigned int get_mems_allowed(void)
  99 {
 100         return read_seqcount_begin(&current->mems_allowed_seq);
 101 }
 102
 103 /*
 104  * If this returns false, the operation that took place after get_mems_allowed
 105  * may have failed. It is up to the caller to retry the operation if
 106  * appropriate.
 107  */
 108 static inline bool put_mems_allowed(unsigned int seq)
 109 {
 110         return !read_seqcount_retry(&current->mems_allowed_seq, seq);
 111 }
 112
 113 static inline void set_mems_allowed(nodemask_t nodemask)
 114 {
 115         task_lock(current);
 116         write_seqcount_begin(&current->mems_allowed_seq);
 117         current->mems_allowed = nodemask;
 118         write_seqcount_end(&current->mems_allowed_seq);
 119         task_unlock(current);
 120 }
 121
 122 #else /* !CONFIG_CPUSETS */
 123
 124 static inline int cpuset_init(void) { return 0; }
 125 static inline void cpuset_init_smp(void) {}
 126
 127 static inline void cpuset_update_active_cpus(void)
 128 {
 129         partition_sched_domains(1, NULL, NULL);
 130 }
 131
 132 static inline void cpuset_cpus_allowed(struct task_struct *p,
 133                                        struct cpumask *mask)
 134 {
 135         cpumask_copy(mask, cpu_possible_mask);
 136 }
 137
 138 static inline void cpuset_cpus_allowed_fallback(struct task_struct *p)
 139 {
 140 }
 141
 142 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
 143 {
 144         return node_possible_map;
 145 }
 146
 147 #define cpuset_current_mems_allowed (node_states[N_HIGH_MEMORY])
 148 static inline void cpuset_init_current_mems_allowed(void) {}
 149
 150 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
 151 {
 152         return 1;
 153 }
 154
 155 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
 156 {
 157         return 1;
 158 }
 159
 160 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
 161 {
 162         return 1;
 163 }
 164
 165 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
 166 {
 167         return 1;
 168 }
 169
 170 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
 171 {
 172         return 1;
 173 }
 174
 175 static inline int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
 176                                                  const struct task_struct *tsk2)
 177 {
 178         return 1;
 179 }
 180
 181 static inline void cpuset_memory_pressure_bump(void) {}
 182
 183 static inline void cpuset_task_status_allowed(struct seq_file *m,
 184                                                 struct task_struct *task)
 185 {
 186 }
 187
 188 static inline int cpuset_mem_spread_node(void)
 189 {
 190         return 0;
 191 }
 192
 193 static inline int cpuset_slab_spread_node(void)
 194 {
 195         return 0;
 196 }
 197
 198 static inline int cpuset_do_page_mem_spread(void)
 199 {
 200         return 0;
 201 }
 202
 203 static inline int cpuset_do_slab_mem_spread(void)
 204 {
 205         return 0;
 206 }
 207
 208 static inline int current_cpuset_is_being_rebound(void)
 209 {
 210         return 0;
 211 }
 212
 213 static inline void rebuild_sched_domains(void)
 214 {
 215         partition_sched_domains(1, NULL, NULL);
 216 }
 217
 218 static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
 219 {
 220 }
 221
 222 static inline void set_mems_allowed(nodemask_t nodemask)
 223 {
 224 }
 225
 226 static inline unsigned int get_mems_allowed(void)
 227 {
 228         return 0;
 229 }
 230
 231 static inline bool put_mems_allowed(unsigned int seq)
 232 {
 233         return true;
 234 }
 235
 236 #endif /* !CONFIG_CPUSETS */
 237
 238 #endif /* _LINUX_CPUSET_H */