/* SPDX-License-Identifier: GPL-2.0-or-later */
/* delayacct.h - per-task delay accounting
 *
 * Copyright (C) Shailabh Nagar, IBM Corp. 2006
 */

#ifndef _LINUX_DELAYACCT_H
#define _LINUX_DELAYACCT_H

#include <uapi/linux/taskstats.h>

#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
        raw_spinlock_t  lock;

        /* For each stat XXX, add following, aligned appropriately
         *
         * struct timespec XXX_start, XXX_end;
         * u64 XXX_delay;
         * u32 XXX_count;
         *
         * Atomicity of updates to XXX_delay, XXX_count protected by
         * single lock above (split into XXX_lock if contention is an issue).
         */

        /*
         * XXX_count is incremented on every XXX operation, the delay
         * associated with the operation is added to XXX_delay.
         * XXX_delay contains the accumulated delay time in nanoseconds.
         */
        u64 blkio_start;
        u64 blkio_delay_max;
        u64 blkio_delay_min;
        u64 blkio_delay;        /* wait for sync block io completion */
        u64 swapin_start;
        u64 swapin_delay_max;
        u64 swapin_delay_min;
        u64 swapin_delay;       /* wait for swapin */
        u32 blkio_count;        /* total count of the number of sync block */
                                /* io operations performed */
        u32 swapin_count;       /* total count of swapin */

        u64 freepages_start;
        u64 freepages_delay_max;
        u64 freepages_delay_min;
        u64 freepages_delay;    /* wait for memory reclaim */

        u64 thrashing_start;
        u64 thrashing_delay_max;
        u64 thrashing_delay_min;
        u64 thrashing_delay;    /* wait for thrashing page */

        u64 compact_start;
        u64 compact_delay_max;
        u64 compact_delay_min;
        u64 compact_delay;      /* wait for memory compact */

        u64 wpcopy_start;
        u64 wpcopy_delay_max;
        u64 wpcopy_delay_min;
        u64 wpcopy_delay;       /* wait for write-protect copy */

        u64 irq_delay_max;
        u64 irq_delay_min;
        u64 irq_delay;  /* wait for IRQ/SOFTIRQ */

        u32 freepages_count;    /* total count of memory reclaim */
        u32 thrashing_count;    /* total count of thrash waits */
        u32 compact_count;      /* total count of memory compact */
        u32 wpcopy_count;       /* total count of write-protect copy */
        u32 irq_count;  /* total count of IRQ/SOFTIRQ */

        struct timespec64 blkio_delay_max_ts;
        struct timespec64 swapin_delay_max_ts;
        struct timespec64 freepages_delay_max_ts;
        struct timespec64 thrashing_delay_max_ts;
        struct timespec64 compact_delay_max_ts;
        struct timespec64 wpcopy_delay_max_ts;
        struct timespec64 irq_delay_max_ts;
};
#endif

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/jump_label.h>

#ifdef CONFIG_TASK_DELAY_ACCT
DECLARE_STATIC_KEY_FALSE(delayacct_key);
extern int delayacct_on;        /* Delay accounting turned on/off */
extern struct kmem_cache *delayacct_cache;
extern void delayacct_init(void);

extern void __delayacct_tsk_init(struct task_struct *);
extern void __delayacct_tsk_exit(struct task_struct *);
extern void __delayacct_blkio_start(void);
extern void __delayacct_blkio_end(struct task_struct *);
extern int delayacct_add_tsk(struct taskstats *, struct task_struct *);
extern __u64 __delayacct_blkio_ticks(struct task_struct *);
extern void __delayacct_freepages_start(void);
extern void __delayacct_freepages_end(void);
extern void __delayacct_thrashing_start(bool *in_thrashing);
extern void __delayacct_thrashing_end(bool *in_thrashing);
extern void __delayacct_swapin_start(void);
extern void __delayacct_swapin_end(void);
extern void __delayacct_compact_start(void);
extern void __delayacct_compact_end(void);
extern void __delayacct_wpcopy_start(void);
extern void __delayacct_wpcopy_end(void);
extern void __delayacct_irq(struct task_struct *task, u32 delta);

static inline void delayacct_tsk_init(struct task_struct *tsk)
{
        /* reinitialize in case parent's non-null pointer was dup'ed*/
        tsk->delays = NULL;
        if (delayacct_on)
                __delayacct_tsk_init(tsk);
}

/* Free tsk->delays. Called from bad fork and __put_task_struct
 * where there's no risk of tsk->delays being accessed elsewhere
 */
static inline void delayacct_tsk_free(struct task_struct *tsk)
{
        if (tsk->delays)
                kmem_cache_free(delayacct_cache, tsk->delays);
        tsk->delays = NULL;
}

static inline void delayacct_blkio_start(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_blkio_start();
}

static inline void delayacct_blkio_end(struct task_struct *p)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (p->delays)
                __delayacct_blkio_end(p);
}

static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
{
        if (tsk->delays)
                return __delayacct_blkio_ticks(tsk);
        return 0;
}

static inline void delayacct_freepages_start(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_freepages_start();
}

static inline void delayacct_freepages_end(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_freepages_end();
}

static inline void delayacct_thrashing_start(bool *in_thrashing)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_thrashing_start(in_thrashing);
}

static inline void delayacct_thrashing_end(bool *in_thrashing)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_thrashing_end(in_thrashing);
}

static inline void delayacct_swapin_start(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_swapin_start();
}

static inline void delayacct_swapin_end(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_swapin_end();
}

static inline void delayacct_compact_start(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_compact_start();
}

static inline void delayacct_compact_end(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_compact_end();
}

static inline void delayacct_wpcopy_start(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_wpcopy_start();
}

static inline void delayacct_wpcopy_end(void)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (current->delays)
                __delayacct_wpcopy_end();
}

static inline void delayacct_irq(struct task_struct *task, u32 delta)
{
        if (!static_branch_unlikely(&delayacct_key))
                return;

        if (task->delays)
                __delayacct_irq(task, delta);
}

#else
static inline void delayacct_init(void)
{}
static inline void delayacct_tsk_init(struct task_struct *tsk)
{}
static inline void delayacct_tsk_free(struct task_struct *tsk)
{}
static inline void delayacct_blkio_start(void)
{}
static inline void delayacct_blkio_end(struct task_struct *p)
{}
static inline int delayacct_add_tsk(struct taskstats *d,
                                        struct task_struct *tsk)
{ return 0; }
static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
{ return 0; }
static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
{ return 0; }
static inline void delayacct_freepages_start(void)
{}
static inline void delayacct_freepages_end(void)
{}
static inline void delayacct_thrashing_start(bool *in_thrashing)
{}
static inline void delayacct_thrashing_end(bool *in_thrashing)
{}
static inline void delayacct_swapin_start(void)
{}
static inline void delayacct_swapin_end(void)
{}
static inline void delayacct_compact_start(void)
{}
static inline void delayacct_compact_end(void)
{}
static inline void delayacct_wpcopy_start(void)
{}
static inline void delayacct_wpcopy_end(void)
{}
static inline void delayacct_irq(struct task_struct *task, u32 delta)
{}

#endif /* CONFIG_TASK_DELAY_ACCT */

#endif