/* SPDX-License-Identifier: GPL-2.0 */
#undef TRACE_SYSTEM
#define TRACE_SYSTEM ksm

#if !defined(_TRACE_KSM_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_KSM_H

#include <linux/tracepoint.h>

/**
 * ksm_scan_template - called for start / stop scan
 *
 * @seq:        sequence number of scan
 * @rmap_entries:    actual number of rmap entries
 *
 * Allows to trace the start / stop of a ksm scan.
 */
DECLARE_EVENT_CLASS(ksm_scan_template,

    TP_PROTO(int seq, u32 rmap_entries),

    TP_ARGS(seq, rmap_entries),

    TP_STRUCT__entry(
        __field(int,    seq)
        __field(u32,    rmap_entries)
    ),

    TP_fast_assign(
        __entry->seq        = seq;
        __entry->rmap_entries    = rmap_entries;
    ),

    TP_printk("seq %d rmap size %d",
            __entry->seq, __entry->rmap_entries)
);

/**
 * ksm_start_scan - called after a new ksm scan is started
 *
 * @seq:        sequence number of scan
 * @rmap_entries:    actual number of rmap entries
 *
 * Allows to trace the start of a ksm scan.
 */
DEFINE_EVENT(ksm_scan_template, ksm_start_scan,

    TP_PROTO(int seq, u32 rmap_entries),

    TP_ARGS(seq, rmap_entries)
);

/**
 * ksm_stop_scan - called after a new ksm scan has completed
 *
 * @seq:        sequence number of scan
 * @rmap_entries:    actual number of rmap entries
 *
 * Allows to trace the completion of a ksm scan.
 */
DEFINE_EVENT(ksm_scan_template, ksm_stop_scan,

    TP_PROTO(int seq, u32 rmap_entries),

    TP_ARGS(seq, rmap_entries)
);

/**
 * ksm_enter - called after a new process has been added / removed from ksm
 *
 * @mm:            address of the mm object of the process
 *
 * Allows to trace the when a process has been added or removed from ksm.
 */
DECLARE_EVENT_CLASS(ksm_enter_exit_template,

    TP_PROTO(void *mm),

    TP_ARGS(mm),

    TP_STRUCT__entry(
        __field(void *,        mm)
    ),

    TP_fast_assign(
        __entry->mm    = mm;
    ),

    TP_printk("mm %p", __entry->mm)
);

/**
 * ksm_enter - called after a new process has been added to ksm
 *
 * @mm:            address of the mm object of the process
 *
 * Allows to trace the when a process has been added to ksm.
 */
DEFINE_EVENT(ksm_enter_exit_template, ksm_enter,

    TP_PROTO(void *mm),

    TP_ARGS(mm)
);

/**
 * ksm_exit - called after a new process has been removed from ksm
 *
 * @mm:            address of the mm object of the process
 *
 * Allows to trace the when a process has been removed from ksm.
 */
DEFINE_EVENT(ksm_enter_exit_template, ksm_exit,

    TP_PROTO(void *mm),

    TP_ARGS(mm)
);

/**
 * ksm_merge_one_page - called after a page has been merged
 *
 * @pfn:        page frame number of ksm page
 * @rmap_item:        address of rmap_item  object
 * @mm:            address of the process mm struct
 * @err:        success
 *
 * Allows to trace the ksm merging of individual pages.
 */
TRACE_EVENT(ksm_merge_one_page,

    TP_PROTO(unsigned long pfn, void *rmap_item, void *mm, int err),

    TP_ARGS(pfn, rmap_item, mm, err),

    TP_STRUCT__entry(
        __field(unsigned long,    pfn)
        __field(void *,        rmap_item)
        __field(void *,        mm)
        __field(int,        err)
    ),

    TP_fast_assign(
        __entry->pfn        = pfn;
        __entry->rmap_item    = rmap_item;
        __entry->mm        = mm;
        __entry->err        = err;
    ),

    TP_printk("ksm pfn %lu rmap_item %p mm %p error %d",
            __entry->pfn, __entry->rmap_item, __entry->mm, __entry->err)
);

/**
 * ksm_merge_with_ksm_page - called after a page has been merged with a ksm page
 *
 * @ksm_page:        address ksm page
 * @pfn:        page frame number of ksm page
 * @rmap_item:        address of rmap_item  object
 * @mm:            address of the mm object of the process
 * @err:        success
 *
 * Allows to trace the merging of a page with a ksm page.
 */
TRACE_EVENT(ksm_merge_with_ksm_page,

    TP_PROTO(void *ksm_page, unsigned long pfn, void *rmap_item, void *mm, int err),

    TP_ARGS(ksm_page, pfn, rmap_item, mm, err),

    TP_STRUCT__entry(
        __field(void *,        ksm_page)
        __field(unsigned long,    pfn)
        __field(void *,        rmap_item)
        __field(void *,        mm)
        __field(int,        err)
    ),

    TP_fast_assign(
        __entry->ksm_page    = ksm_page;
        __entry->pfn        = pfn;
        __entry->rmap_item    = rmap_item;
        __entry->mm        = mm;
        __entry->err        = err;
    ),

    TP_printk("%spfn %lu rmap_item %p mm %p error %d",
          (__entry->ksm_page ? "ksm " : ""),
          __entry->pfn, __entry->rmap_item, __entry->mm, __entry->err)
);

/**
 * ksm_remove_ksm_page - called after a ksm page has been removed
 *
 * @pfn:        page frame number of ksm page
 *
 * Allows to trace the removing of stable ksm pages.
 */
TRACE_EVENT(ksm_remove_ksm_page,

    TP_PROTO(unsigned long pfn),

    TP_ARGS(pfn),

    TP_STRUCT__entry(
        __field(unsigned long, pfn)
    ),

    TP_fast_assign(
        __entry->pfn = pfn;
    ),

    TP_printk("pfn %lu", __entry->pfn)
);

/**
 * ksm_remove_rmap_item - called after a rmap_item has been removed from the
 *                        stable tree
 *
 * @pfn:        page frame number of ksm page
 * @rmap_item:        address of rmap_item  object
 * @mm:            address of the process mm struct
 *
 * Allows to trace the removal of pages from the stable tree list.
 */
TRACE_EVENT(ksm_remove_rmap_item,

    TP_PROTO(unsigned long pfn, void *rmap_item, void *mm),

    TP_ARGS(pfn, rmap_item, mm),

    TP_STRUCT__entry(
        __field(unsigned long,    pfn)
        __field(void *,        rmap_item)
        __field(void *,        mm)
    ),

    TP_fast_assign(
        __entry->pfn        = pfn;
        __entry->rmap_item    = rmap_item;
        __entry->mm        = mm;
    ),

    TP_printk("pfn %lu rmap_item %p mm %p",
            __entry->pfn, __entry->rmap_item, __entry->mm)
);

#endif /* _TRACE_KSM_H */

/* This part must be outside protection */
#include <trace/define_trace.h>