1 #ifndef __INCLUDE_LINUX_OOM_H 2 #define __INCLUDE_LINUX_OOM_H 3 4 5 #include <linux/sched/signal.h> 6 #include <linux/types.h> 7 #include <linux/nodemask.h> 8 #include <uapi/linux/oom.h> 9 #include <linux/sched/coredump.h> /* MMF_* */ 10 #include <linux/mm.h> /* VM_FAULT* */ 11 12 struct zonelist; 13 struct notifier_block; 14 struct mem_cgroup; 15 struct task_struct; 16 17 /* 18 * Details of the page allocation that triggered the oom killer that are used to 19 * determine what should be killed. 20 */ 21 struct oom_control { 22 /* Used to determine cpuset */ 23 struct zonelist *zonelist; 24 25 /* Used to determine mempolicy */ 26 nodemask_t *nodemask; 27 28 /* Memory cgroup in which oom is invoked, or NULL for global oom */ 29 struct mem_cgroup *memcg; 30 31 /* Used to determine cpuset and node locality requirement */ 32 const gfp_t gfp_mask; 33 34 /* 35 * order == -1 means the oom kill is required by sysrq, otherwise only 36 * for display purposes. 37 */ 38 const int order; 39 40 /* Used by oom implementation, do not set */ 41 unsigned long totalpages; 42 struct task_struct *chosen; 43 unsigned long chosen_points; 44 }; 45 46 extern struct mutex oom_lock; 47 48 static inline void set_current_oom_origin(void) 49 { 50 current->signal->oom_flag_origin = true; 51 } 52 53 static inline void clear_current_oom_origin(void) 54 { 55 current->signal->oom_flag_origin = false; 56 } 57 58 static inline bool oom_task_origin(const struct task_struct *p) 59 { 60 return p->signal->oom_flag_origin; 61 } 62 63 static inline bool tsk_is_oom_victim(struct task_struct * tsk) 64 { 65 return tsk->signal->oom_mm; 66 } 67 68 /* 69 * Checks whether a page fault on the given mm is still reliable. 70 * This is no longer true if the oom reaper started to reap the 71 * address space which is reflected by MMF_UNSTABLE flag set in 72 * the mm. At that moment any !shared mapping would lose the content 73 * and could cause a memory corruption (zero pages instead of the 74 * original content). 75 * 76 * User should call this before establishing a page table entry for 77 * a !shared mapping and under the proper page table lock. 78 * 79 * Return 0 when the PF is safe VM_FAULT_SIGBUS otherwise. 80 */ 81 static inline int check_stable_address_space(struct mm_struct *mm) 82 { 83 if (unlikely(test_bit(MMF_UNSTABLE, &mm->flags))) 84 return VM_FAULT_SIGBUS; 85 return 0; 86 } 87 88 extern unsigned long oom_badness(struct task_struct *p, 89 struct mem_cgroup *memcg, const nodemask_t *nodemask, 90 unsigned long totalpages); 91 92 extern bool out_of_memory(struct oom_control *oc); 93 94 extern void exit_oom_victim(void); 95 96 extern int register_oom_notifier(struct notifier_block *nb); 97 extern int unregister_oom_notifier(struct notifier_block *nb); 98 99 extern bool oom_killer_disable(signed long timeout); 100 extern void oom_killer_enable(void); 101 102 extern struct task_struct *find_lock_task_mm(struct task_struct *p); 103 104 /* sysctls */ 105 extern int sysctl_oom_dump_tasks; 106 extern int sysctl_oom_kill_allocating_task; 107 extern int sysctl_panic_on_oom; 108 #endif /* _INCLUDE_LINUX_OOM_H */ 109