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

#include <linux/ceph/types.h>
#include <linux/percpu_counter.h>
#include <linux/ktime.h>

extern bool disable_send_metrics;

enum ceph_metric_type {
        CLIENT_METRIC_TYPE_CAP_INFO,
        CLIENT_METRIC_TYPE_READ_LATENCY,
        CLIENT_METRIC_TYPE_WRITE_LATENCY,
        CLIENT_METRIC_TYPE_METADATA_LATENCY,
        CLIENT_METRIC_TYPE_DENTRY_LEASE,
        CLIENT_METRIC_TYPE_OPENED_FILES,
        CLIENT_METRIC_TYPE_PINNED_ICAPS,
        CLIENT_METRIC_TYPE_OPENED_INODES,
        CLIENT_METRIC_TYPE_READ_IO_SIZES,
        CLIENT_METRIC_TYPE_WRITE_IO_SIZES,
        CLIENT_METRIC_TYPE_AVG_READ_LATENCY,
        CLIENT_METRIC_TYPE_STDEV_READ_LATENCY,
        CLIENT_METRIC_TYPE_AVG_WRITE_LATENCY,
        CLIENT_METRIC_TYPE_STDEV_WRITE_LATENCY,
        CLIENT_METRIC_TYPE_AVG_METADATA_LATENCY,
        CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY,

        CLIENT_METRIC_TYPE_MAX = CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY,
};

/*
 * This will always have the highest metric bit value
 * as the last element of the array.
 */
#define CEPHFS_METRIC_SPEC_CLIENT_SUPPORTED {      \
        CLIENT_METRIC_TYPE_CAP_INFO,               \
        CLIENT_METRIC_TYPE_READ_LATENCY,           \
        CLIENT_METRIC_TYPE_WRITE_LATENCY,          \
        CLIENT_METRIC_TYPE_METADATA_LATENCY,       \
        CLIENT_METRIC_TYPE_DENTRY_LEASE,           \
        CLIENT_METRIC_TYPE_OPENED_FILES,           \
        CLIENT_METRIC_TYPE_PINNED_ICAPS,           \
        CLIENT_METRIC_TYPE_OPENED_INODES,          \
        CLIENT_METRIC_TYPE_READ_IO_SIZES,          \
        CLIENT_METRIC_TYPE_WRITE_IO_SIZES,         \
        CLIENT_METRIC_TYPE_AVG_READ_LATENCY,       \
        CLIENT_METRIC_TYPE_STDEV_READ_LATENCY,     \
        CLIENT_METRIC_TYPE_AVG_WRITE_LATENCY,      \
        CLIENT_METRIC_TYPE_STDEV_WRITE_LATENCY,    \
        CLIENT_METRIC_TYPE_AVG_METADATA_LATENCY,   \
        CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY, \
                                                   \
        CLIENT_METRIC_TYPE_MAX,                    \
}

struct ceph_metric_header {
        __le32 type;     /* ceph metric type */
        __u8  ver;
        __u8  compat;
        __le32 data_len; /* length of sizeof(hit + mis + total) */
} __packed;

/* metric caps header */
struct ceph_metric_cap {
        struct ceph_metric_header header;
        __le64 hit;
        __le64 mis;
        __le64 total;
} __packed;

/* metric read latency header */
struct ceph_metric_read_latency {
        struct ceph_metric_header header;
        struct ceph_timespec lat;
        struct ceph_timespec avg;
        __le64 sq_sum;
        __le64 count;
} __packed;

/* metric write latency header */
struct ceph_metric_write_latency {
        struct ceph_metric_header header;
        struct ceph_timespec lat;
        struct ceph_timespec avg;
        __le64 sq_sum;
        __le64 count;
} __packed;

/* metric metadata latency header */
struct ceph_metric_metadata_latency {
        struct ceph_metric_header header;
        struct ceph_timespec lat;
        struct ceph_timespec avg;
        __le64 sq_sum;
        __le64 count;
} __packed;

/* metric dentry lease header */
struct ceph_metric_dlease {
        struct ceph_metric_header header;
        __le64 hit;
        __le64 mis;
        __le64 total;
} __packed;

/* metric opened files header */
struct ceph_opened_files {
        struct ceph_metric_header header;
        __le64 opened_files;
        __le64 total;
} __packed;

/* metric pinned i_caps header */
struct ceph_pinned_icaps {
        struct ceph_metric_header header;
        __le64 pinned_icaps;
        __le64 total;
} __packed;

/* metric opened inodes header */
struct ceph_opened_inodes {
        struct ceph_metric_header header;
        __le64 opened_inodes;
        __le64 total;
} __packed;

/* metric read io size header */
struct ceph_read_io_size {
        struct ceph_metric_header header;
        __le64 total_ops;
        __le64 total_size;
} __packed;

/* metric write io size header */
struct ceph_write_io_size {
        struct ceph_metric_header header;
        __le64 total_ops;
        __le64 total_size;
} __packed;

struct ceph_metric_head {
        __le32 num;     /* the number of metrics that will be sent */
} __packed;

enum metric_type {
        METRIC_READ,
        METRIC_WRITE,
        METRIC_METADATA,
        METRIC_COPYFROM,
        METRIC_MAX
};

struct ceph_metric {
        spinlock_t lock;
        u64 total;
        u64 size_sum;
        u64 size_min;
        u64 size_max;
        ktime_t latency_sum;
        ktime_t latency_avg;
        ktime_t latency_sq_sum;
        ktime_t latency_min;
        ktime_t latency_max;
};

/* This is the global metrics */
struct ceph_client_metric {
        atomic64_t            total_dentries;
        struct percpu_counter d_lease_hit;
        struct percpu_counter d_lease_mis;

        atomic64_t            total_caps;
        struct percpu_counter i_caps_hit;
        struct percpu_counter i_caps_mis;

        struct ceph_metric metric[METRIC_MAX];

        /* The total number of directories and files that are opened */
        atomic64_t opened_files;

        /* The total number of inodes that have opened files or directories */
        struct percpu_counter opened_inodes;
        struct percpu_counter total_inodes;

        struct ceph_mds_session *session;
        struct delayed_work delayed_work;  /* delayed work */
};

static inline void metric_schedule_delayed(struct ceph_client_metric *m)
{
        if (disable_send_metrics)
                return;

        /* per second */
        schedule_delayed_work(&m->delayed_work, round_jiffies_relative(HZ));
}

extern int ceph_metric_init(struct ceph_client_metric *m);
extern void ceph_metric_destroy(struct ceph_client_metric *m);

static inline void ceph_update_cap_hit(struct ceph_client_metric *m)
{
        percpu_counter_inc(&m->i_caps_hit);
}

static inline void ceph_update_cap_mis(struct ceph_client_metric *m)
{
        percpu_counter_inc(&m->i_caps_mis);
}

extern void ceph_update_metrics(struct ceph_metric *m,
                                ktime_t r_start, ktime_t r_end,
                                unsigned int size, int rc);

static inline void ceph_update_read_metrics(struct ceph_client_metric *m,
                                            ktime_t r_start, ktime_t r_end,
                                            unsigned int size, int rc)
{
        ceph_update_metrics(&m->metric[METRIC_READ],
                            r_start, r_end, size, rc);
}
static inline void ceph_update_write_metrics(struct ceph_client_metric *m,
                                             ktime_t r_start, ktime_t r_end,
                                             unsigned int size, int rc)
{
        ceph_update_metrics(&m->metric[METRIC_WRITE],
                            r_start, r_end, size, rc);
}
static inline void ceph_update_metadata_metrics(struct ceph_client_metric *m,
                                                ktime_t r_start, ktime_t r_end,
                                                int rc)
{
        ceph_update_metrics(&m->metric[METRIC_METADATA],
                            r_start, r_end, 0, rc);
}
static inline void ceph_update_copyfrom_metrics(struct ceph_client_metric *m,
                                                ktime_t r_start, ktime_t r_end,
                                                unsigned int size, int rc)
{
        ceph_update_metrics(&m->metric[METRIC_COPYFROM],
                            r_start, r_end, size, rc);
}
#endif /* _FS_CEPH_MDS_METRIC_H */