1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __INCLUDE_LINUX_OOM_H 2 #ifndef __INCLUDE_LINUX_OOM_H
3 #define __INCLUDE_LINUX_OOM_H 3 #define __INCLUDE_LINUX_OOM_H
4 4
5 5
6 #include <linux/sched/signal.h> 6 #include <linux/sched/signal.h>
7 #include <linux/types.h> 7 #include <linux/types.h>
8 #include <linux/nodemask.h> 8 #include <linux/nodemask.h>
9 #include <uapi/linux/oom.h> 9 #include <uapi/linux/oom.h>
10 #include <linux/sched/coredump.h> /* MMF_* */ 10 #include <linux/sched/coredump.h> /* MMF_* */
11 #include <linux/mm.h> /* VM_FAULT* */ 11 #include <linux/mm.h> /* VM_FAULT* */
12 12
13 struct zonelist; 13 struct zonelist;
14 struct notifier_block; 14 struct notifier_block;
15 struct mem_cgroup; 15 struct mem_cgroup;
16 struct task_struct; 16 struct task_struct;
17 17
18 enum oom_constraint { 18 enum oom_constraint {
19 CONSTRAINT_NONE, 19 CONSTRAINT_NONE,
20 CONSTRAINT_CPUSET, 20 CONSTRAINT_CPUSET,
21 CONSTRAINT_MEMORY_POLICY, 21 CONSTRAINT_MEMORY_POLICY,
22 CONSTRAINT_MEMCG, 22 CONSTRAINT_MEMCG,
23 }; 23 };
24 24
25 /* 25 /*
26 * Details of the page allocation that trigger 26 * Details of the page allocation that triggered the oom killer that are used to
27 * determine what should be killed. 27 * determine what should be killed.
28 */ 28 */
29 struct oom_control { 29 struct oom_control {
30 /* Used to determine cpuset */ 30 /* Used to determine cpuset */
31 struct zonelist *zonelist; 31 struct zonelist *zonelist;
32 32
33 /* Used to determine mempolicy */ 33 /* Used to determine mempolicy */
34 nodemask_t *nodemask; 34 nodemask_t *nodemask;
35 35
36 /* Memory cgroup in which oom is invok 36 /* Memory cgroup in which oom is invoked, or NULL for global oom */
37 struct mem_cgroup *memcg; 37 struct mem_cgroup *memcg;
38 38
39 /* Used to determine cpuset and node l 39 /* Used to determine cpuset and node locality requirement */
40 const gfp_t gfp_mask; 40 const gfp_t gfp_mask;
41 41
42 /* 42 /*
43 * order == -1 means the oom kill is r 43 * order == -1 means the oom kill is required by sysrq, otherwise only
44 * for display purposes. 44 * for display purposes.
45 */ 45 */
46 const int order; 46 const int order;
47 47
48 /* Used by oom implementation, do not 48 /* Used by oom implementation, do not set */
49 unsigned long totalpages; 49 unsigned long totalpages;
50 struct task_struct *chosen; 50 struct task_struct *chosen;
51 long chosen_points; 51 long chosen_points;
52 52
53 /* Used to print the constraint info. 53 /* Used to print the constraint info. */
54 enum oom_constraint constraint; 54 enum oom_constraint constraint;
55 }; 55 };
56 56
57 extern struct mutex oom_lock; 57 extern struct mutex oom_lock;
58 extern struct mutex oom_adj_mutex; 58 extern struct mutex oom_adj_mutex;
59 59
60 static inline void set_current_oom_origin(void 60 static inline void set_current_oom_origin(void)
61 { 61 {
62 current->signal->oom_flag_origin = tru 62 current->signal->oom_flag_origin = true;
63 } 63 }
64 64
65 static inline void clear_current_oom_origin(vo 65 static inline void clear_current_oom_origin(void)
66 { 66 {
67 current->signal->oom_flag_origin = fal 67 current->signal->oom_flag_origin = false;
68 } 68 }
69 69
70 static inline bool oom_task_origin(const struc 70 static inline bool oom_task_origin(const struct task_struct *p)
71 { 71 {
72 return p->signal->oom_flag_origin; 72 return p->signal->oom_flag_origin;
73 } 73 }
74 74
75 static inline bool tsk_is_oom_victim(struct ta 75 static inline bool tsk_is_oom_victim(struct task_struct * tsk)
76 { 76 {
77 return tsk->signal->oom_mm; 77 return tsk->signal->oom_mm;
78 } 78 }
79 79
80 /* 80 /*
81 * Checks whether a page fault on the given mm 81 * Checks whether a page fault on the given mm is still reliable.
82 * This is no longer true if the oom reaper st 82 * This is no longer true if the oom reaper started to reap the
83 * address space which is reflected by MMF_UNS 83 * address space which is reflected by MMF_UNSTABLE flag set in
84 * the mm. At that moment any !shared mapping 84 * the mm. At that moment any !shared mapping would lose the content
85 * and could cause a memory corruption (zero p 85 * and could cause a memory corruption (zero pages instead of the
86 * original content). 86 * original content).
87 * 87 *
88 * User should call this before establishing a 88 * User should call this before establishing a page table entry for
89 * a !shared mapping and under the proper page 89 * a !shared mapping and under the proper page table lock.
90 * 90 *
91 * Return 0 when the PF is safe VM_FAULT_SIGBU 91 * Return 0 when the PF is safe VM_FAULT_SIGBUS otherwise.
92 */ 92 */
93 static inline vm_fault_t check_stable_address_ 93 static inline vm_fault_t check_stable_address_space(struct mm_struct *mm)
94 { 94 {
95 if (unlikely(test_bit(MMF_UNSTABLE, &m 95 if (unlikely(test_bit(MMF_UNSTABLE, &mm->flags)))
96 return VM_FAULT_SIGBUS; 96 return VM_FAULT_SIGBUS;
97 return 0; 97 return 0;
98 } 98 }
99 99
100 long oom_badness(struct task_struct *p, 100 long oom_badness(struct task_struct *p,
101 unsigned long totalpages); 101 unsigned long totalpages);
102 102
103 extern bool out_of_memory(struct oom_control * 103 extern bool out_of_memory(struct oom_control *oc);
104 104
105 extern void exit_oom_victim(void); 105 extern void exit_oom_victim(void);
106 106
107 extern int register_oom_notifier(struct notifi 107 extern int register_oom_notifier(struct notifier_block *nb);
108 extern int unregister_oom_notifier(struct noti 108 extern int unregister_oom_notifier(struct notifier_block *nb);
109 109
110 extern bool oom_killer_disable(signed long tim 110 extern bool oom_killer_disable(signed long timeout);
111 extern void oom_killer_enable(void); 111 extern void oom_killer_enable(void);
112 112
113 extern struct task_struct *find_lock_task_mm(s 113 extern struct task_struct *find_lock_task_mm(struct task_struct *p);
114 114
115 #endif /* _INCLUDE_LINUX_OOM_H */ 115 #endif /* _INCLUDE_LINUX_OOM_H */
116 116
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