include/linux/oom.h

   1 #ifndef __INCLUDE_LINUX_OOM_H
   2 #define __INCLUDE_LINUX_OOM_H
   3
   4
   5 #include <linux/sched.h>
   6 #include <linux/types.h>
   7 #include <linux/nodemask.h>
   8 #include <uapi/linux/oom.h>
   9
  10 struct zonelist;
  11 struct notifier_block;
  12 struct mem_cgroup;
  13 struct task_struct;
  14
  15 /*
  16  * Details of the page allocation that triggered the oom killer that are used to
  17  * determine what should be killed.
  18  */
  19 struct oom_control {
  20         /* Used to determine cpuset */
  21         struct zonelist *zonelist;
  22
  23         /* Used to determine mempolicy */
  24         nodemask_t *nodemask;
  25
  26         /* Memory cgroup in which oom is invoked, or NULL for global oom */
  27         struct mem_cgroup *memcg;
  28
  29         /* Used to determine cpuset and node locality requirement */
  30         const gfp_t gfp_mask;
  31
  32         /*
  33          * order == -1 means the oom kill is required by sysrq, otherwise only
  34          * for display purposes.
  35          */
  36         const int order;
  37 };
  38
  39 /*
  40  * Types of limitations to the nodes from which allocations may occur
  41  */
  42 enum oom_constraint {
  43         CONSTRAINT_NONE,
  44         CONSTRAINT_CPUSET,
  45         CONSTRAINT_MEMORY_POLICY,
  46         CONSTRAINT_MEMCG,
  47 };
  48
  49 enum oom_scan_t {
  50         OOM_SCAN_OK,            /* scan thread and find its badness */
  51         OOM_SCAN_CONTINUE,      /* do not consider thread for oom kill */
  52         OOM_SCAN_ABORT,         /* abort the iteration and return */
  53         OOM_SCAN_SELECT,        /* always select this thread first */
  54 };
  55
  56 extern struct mutex oom_lock;
  57
  58 static inline void set_current_oom_origin(void)
  59 {
  60         current->signal->oom_flag_origin = true;
  61 }
  62
  63 static inline void clear_current_oom_origin(void)
  64 {
  65         current->signal->oom_flag_origin = false;
  66 }
  67
  68 static inline bool oom_task_origin(const struct task_struct *p)
  69 {
  70         return p->signal->oom_flag_origin;
  71 }
  72
  73 extern void mark_oom_victim(struct task_struct *tsk);
  74
  75 #ifdef CONFIG_MMU
  76 extern void wake_oom_reaper(struct task_struct *tsk);
  77 #else
  78 static inline void wake_oom_reaper(struct task_struct *tsk)
  79 {
  80 }
  81 #endif
  82
  83 extern unsigned long oom_badness(struct task_struct *p,
  84                 struct mem_cgroup *memcg, const nodemask_t *nodemask,
  85                 unsigned long totalpages);
  86
  87 extern void oom_kill_process(struct oom_control *oc, struct task_struct *p,
  88                              unsigned int points, unsigned long totalpages,
  89                              const char *message);
  90
  91 extern void check_panic_on_oom(struct oom_control *oc,
  92                                enum oom_constraint constraint);
  93
  94 extern enum oom_scan_t oom_scan_process_thread(struct oom_control *oc,
  95                                                struct task_struct *task);
  96
  97 extern bool out_of_memory(struct oom_control *oc);
  98
  99 extern void exit_oom_victim(struct task_struct *tsk);
 100
 101 extern int register_oom_notifier(struct notifier_block *nb);
 102 extern int unregister_oom_notifier(struct notifier_block *nb);
 103
 104 extern bool oom_killer_disabled;
 105 extern bool oom_killer_disable(void);
 106 extern void oom_killer_enable(void);
 107
 108 extern struct task_struct *find_lock_task_mm(struct task_struct *p);
 109
 110 bool task_will_free_mem(struct task_struct *task);
 111
 112 /* sysctls */
 113 extern int sysctl_oom_dump_tasks;
 114 extern int sysctl_oom_kill_allocating_task;
 115 extern int sysctl_panic_on_oom;
 116 #endif /* _INCLUDE_LINUX_OOM_H */