1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _KERNEL_SCHED_AUTOGROUP_H
3 #define _KERNEL_SCHED_AUTOGROUP_H
4 
5 #ifdef CONFIG_SCHED_AUTOGROUP
6 
7 struct autogroup {
8 	/*
9 	 * Reference doesn't mean how many threads attach to this
10 	 * autogroup now. It just stands for the number of tasks
11 	 * which could use this autogroup.
12 	 */
13 	struct kref		kref;
14 	struct task_group	*tg;
15 	struct rw_semaphore	lock;
16 	unsigned long		id;
17 	int			nice;
18 };
19 
20 extern void autogroup_init(struct task_struct *init_task);
21 extern void autogroup_free(struct task_group *tg);
22 
task_group_is_autogroup(struct task_group * tg)23 static inline bool task_group_is_autogroup(struct task_group *tg)
24 {
25 	return !!tg->autogroup;
26 }
27 
28 extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg);
29 
30 static inline struct task_group *
autogroup_task_group(struct task_struct * p,struct task_group * tg)31 autogroup_task_group(struct task_struct *p, struct task_group *tg)
32 {
33 	extern unsigned int sysctl_sched_autogroup_enabled;
34 	int enabled = READ_ONCE(sysctl_sched_autogroup_enabled);
35 
36 	if (enabled && task_wants_autogroup(p, tg))
37 		return p->signal->autogroup->tg;
38 
39 	return tg;
40 }
41 
42 extern int autogroup_path(struct task_group *tg, char *buf, int buflen);
43 
44 #else /* !CONFIG_SCHED_AUTOGROUP */
45 
autogroup_init(struct task_struct * init_task)46 static inline void autogroup_init(struct task_struct *init_task) {  }
autogroup_free(struct task_group * tg)47 static inline void autogroup_free(struct task_group *tg) { }
task_group_is_autogroup(struct task_group * tg)48 static inline bool task_group_is_autogroup(struct task_group *tg)
49 {
50 	return 0;
51 }
52 
53 static inline struct task_group *
autogroup_task_group(struct task_struct * p,struct task_group * tg)54 autogroup_task_group(struct task_struct *p, struct task_group *tg)
55 {
56 	return tg;
57 }
58 
autogroup_path(struct task_group * tg,char * buf,int buflen)59 static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
60 {
61 	return 0;
62 }
63 
64 #endif /* CONFIG_SCHED_AUTOGROUP */
65 
66 #endif /* _KERNEL_SCHED_AUTOGROUP_H */
67