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/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         task_lock(current);
 114         write_seqcount_begin(&current->mems_allowed_seq);
 115         current->mems_allowed = nodemask;
 116         write_seqcount_end(&current->mems_allowed_seq);
 117         task_unlock(current);
 118 }
 119
 120 #else /* !CONFIG_CPUSETS */
 121
 122 static inline int cpuset_init(void) { return 0; }
 123 static inline void cpuset_init_smp(void) {}
 124
 125 static inline void cpuset_update_active_cpus(bool cpu_online)
 126 {
 127         partition_sched_domains(1, NULL, NULL);
 128 }
 129
 130 static inline void cpuset_cpus_allowed(struct task_struct *p,
 131                                        struct cpumask *mask)
 132 {
 133         cpumask_copy(mask, cpu_possible_mask);
 134 }
 135
 136 static inline void cpuset_cpus_allowed_fallback(struct task_struct *p)
 137 {
 138 }
 139
 140 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
 141 {
 142         return node_possible_map;
 143 }
 144
 145 #define cpuset_current_mems_allowed (node_states[N_MEMORY])
 146 static inline void cpuset_init_current_mems_allowed(void) {}
 147
 148 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
 149 {
 150         return 1;
 151 }
 152
 153 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
 154 {
 155         return 1;
 156 }
 157
 158 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
 159 {
 160         return 1;
 161 }
 162
 163 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
 164 {
 165         return 1;
 166 }
 167
 168 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
 169 {
 170         return 1;
 171 }
 172
 173 static inline int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
 174                                                  const struct task_struct *tsk2)
 175 {
 176         return 1;
 177 }
 178
 179 static inline void cpuset_memory_pressure_bump(void) {}
 180
 181 static inline void cpuset_task_status_allowed(struct seq_file *m,
 182                                                 struct task_struct *task)
 183 {
 184 }
 185
 186 static inline int cpuset_mem_spread_node(void)
 187 {
 188         return 0;
 189 }
 190
 191 static inline int cpuset_slab_spread_node(void)
 192 {
 193         return 0;
 194 }
 195
 196 static inline int cpuset_do_page_mem_spread(void)
 197 {
 198         return 0;
 199 }
 200
 201 static inline int cpuset_do_slab_mem_spread(void)
 202 {
 203         return 0;
 204 }
 205
 206 static inline int current_cpuset_is_being_rebound(void)
 207 {
 208         return 0;
 209 }
 210
 211 static inline void rebuild_sched_domains(void)
 212 {
 213         partition_sched_domains(1, NULL, NULL);
 214 }
 215
 216 static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
 217 {
 218 }
 219
 220 static inline void set_mems_allowed(nodemask_t nodemask)
 221 {
 222 }
 223
 224 static inline unsigned int get_mems_allowed(void)
 225 {
 226         return 0;
 227 }
 228
 229 static inline bool put_mems_allowed(unsigned int seq)
 230 {
 231         return true;
 232 }
 233
 234 #endif /* !CONFIG_CPUSETS */
 235
 236 #endif /* _LINUX_CPUSET_H */