/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _KERNEL_SCHED_AUTOGROUP_H
#define _KERNEL_SCHED_AUTOGROUP_H

#include "sched.h"

#ifdef CONFIG_SCHED_AUTOGROUP

struct autogroup {
        /*
         * Reference doesn't mean how many threads attach to this
         * autogroup now. It just stands for the number of tasks
         * which could use this autogroup.
         */
        struct kref             kref;
        struct task_group       *tg;
        struct rw_semaphore     lock;
        unsigned long           id;
        int                     nice;
};

extern void autogroup_init(struct task_struct *init_task);
extern void autogroup_free(struct task_group *tg);

static inline bool task_group_is_autogroup(struct task_group *tg)
{
        return !!tg->autogroup;
}

extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg);

static inline struct task_group *
autogroup_task_group(struct task_struct *p, struct task_group *tg)
{
        extern unsigned int sysctl_sched_autogroup_enabled;
        int enabled = READ_ONCE(sysctl_sched_autogroup_enabled);

        if (enabled && task_wants_autogroup(p, tg))
                return p->signal->autogroup->tg;

        return tg;
}

extern int autogroup_path(struct task_group *tg, char *buf, int buflen);

#else /* !CONFIG_SCHED_AUTOGROUP: */

static inline void autogroup_init(struct task_struct *init_task) {  }
static inline void autogroup_free(struct task_group *tg) { }
static inline bool task_group_is_autogroup(struct task_group *tg)
{
        return 0;
}

static inline struct task_group *
autogroup_task_group(struct task_struct *p, struct task_group *tg)
{
        return tg;
}

static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
{
        return 0;
}

#endif /* !CONFIG_SCHED_AUTOGROUP */

#endif /* _KERNEL_SCHED_AUTOGROUP_H */