xref: /openbmc/linux/kernel/sched/autogroup.h (revision 842ed298)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifdef CONFIG_SCHED_AUTOGROUP
3 
4 struct autogroup {
5 	/*
6 	 * Reference doesn't mean how many threads attach to this
7 	 * autogroup now. It just stands for the number of tasks
8 	 * which could use this autogroup.
9 	 */
10 	struct kref		kref;
11 	struct task_group	*tg;
12 	struct rw_semaphore	lock;
13 	unsigned long		id;
14 	int			nice;
15 };
16 
17 extern void autogroup_init(struct task_struct *init_task);
18 extern void autogroup_free(struct task_group *tg);
19 
20 static inline bool task_group_is_autogroup(struct task_group *tg)
21 {
22 	return !!tg->autogroup;
23 }
24 
25 extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg);
26 
27 static inline struct task_group *
28 autogroup_task_group(struct task_struct *p, struct task_group *tg)
29 {
30 	int enabled = READ_ONCE(sysctl_sched_autogroup_enabled);
31 
32 	if (enabled && task_wants_autogroup(p, tg))
33 		return p->signal->autogroup->tg;
34 
35 	return tg;
36 }
37 
38 extern int autogroup_path(struct task_group *tg, char *buf, int buflen);
39 
40 #else /* !CONFIG_SCHED_AUTOGROUP */
41 
42 static inline void autogroup_init(struct task_struct *init_task) {  }
43 static inline void autogroup_free(struct task_group *tg) { }
44 static inline bool task_group_is_autogroup(struct task_group *tg)
45 {
46 	return 0;
47 }
48 
49 static inline struct task_group *
50 autogroup_task_group(struct task_struct *p, struct task_group *tg)
51 {
52 	return tg;
53 }
54 
55 static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
56 {
57 	return 0;
58 }
59 
60 #endif /* CONFIG_SCHED_AUTOGROUP */
61