autogroup.h

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