root/include/linux/trace_events.h
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _LINUX_TRACE_EVENT_H
#define _LINUX_TRACE_EVENT_H

#include <linux/ring_buffer.h>
#include <linux/trace_seq.h>
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/perf_event.h>
#include <linux/tracepoint.h>

struct trace_array;
struct array_buffer;
struct tracer;
struct dentry;
struct bpf_prog;
union bpf_attr;

/* Used for event string fields when they are NULL */
#define EVENT_NULL_STR          "(null)"

const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
                                  unsigned long flags,
                                  const struct trace_print_flags *flag_array);

const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
                                    const struct trace_print_flags *symbol_array);

#if BITS_PER_LONG == 32
const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
                      unsigned long long flags,
                      const struct trace_print_flags_u64 *flag_array);

const char *trace_print_symbols_seq_u64(struct trace_seq *p,
                                        unsigned long long val,
                                        const struct trace_print_flags_u64
                                                                 *symbol_array);
#endif

struct trace_iterator;
struct trace_event;

const char *trace_print_bitmask_seq(struct trace_iterator *iter, void *bitmask_ptr,
                                    unsigned int bitmask_size);

const char *trace_print_hex_seq(struct trace_seq *p,
                                const unsigned char *buf, int len,
                                bool concatenate);

const char *trace_print_array_seq(struct trace_seq *p,
                                   const void *buf, int count,
                                   size_t el_size);

const char *
trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
                         int prefix_type, int rowsize, int groupsize,
                         const void *buf, size_t len, bool ascii);

int trace_raw_output_prep(struct trace_iterator *iter,
                          struct trace_event *event);
extern __printf(2, 3)
void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...);

/* Used to find the offset and length of dynamic fields in trace events */
struct trace_dynamic_info {
#ifdef CONFIG_CPU_BIG_ENDIAN
        u16     len;
        u16     offset;
#else
        u16     offset;
        u16     len;
#endif
} __packed;

/*
 * The trace entry - the most basic unit of tracing. This is what
 * is printed in the end as a single line in the trace output, such as:
 *
 *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
 */
struct trace_entry {
        unsigned short          type;
        unsigned char           flags;
        unsigned char           preempt_count;
        int                     pid;
};

#define TRACE_EVENT_TYPE_MAX                                            \
        ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)

/*
 * Trace iterator - used by printout routines who present trace
 * results to users and which routines might sleep, etc:
 */
struct trace_iterator {
        struct trace_array      *tr;
        struct tracer           *trace;
        struct array_buffer     *array_buffer;
        void                    *private;
        int                     cpu_file;
        struct mutex            mutex;
        struct ring_buffer_iter **buffer_iter;
        unsigned long           iter_flags;
        void                    *temp;  /* temp holder */
        unsigned int            temp_size;
        char                    *fmt;   /* modified format holder */
        unsigned int            fmt_size;
        atomic_t                wait_index;

        /* trace_seq for __print_flags() and __print_symbolic() etc. */
        struct trace_seq        tmp_seq;

        cpumask_var_t           started;

        /* Set when the file is closed to prevent new waiters */
        bool                    closed;

        /* it's true when current open file is snapshot */
        bool                    snapshot;

        /* The below is zeroed out in pipe_read */
        struct trace_seq        seq;
        struct trace_entry      *ent;
        unsigned long           lost_events;
        int                     leftover;
        int                     ent_size;
        int                     cpu;
        u64                     ts;

        loff_t                  pos;
        long                    idx;

        /* All new field here will be zeroed out in pipe_read */
};

enum trace_iter_flags {
        TRACE_FILE_LAT_FMT      = 1,
        TRACE_FILE_ANNOTATE     = 2,
        TRACE_FILE_TIME_IN_NS   = 4,
        TRACE_FILE_PAUSE        = 8,
};


typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
                                      int flags, struct trace_event *event);

struct trace_event_functions {
        trace_print_func        trace;
        trace_print_func        raw;
        trace_print_func        hex;
        trace_print_func        binary;
};

struct trace_event {
        struct hlist_node               node;
        int                             type;
        struct trace_event_functions    *funcs;
};

extern int register_trace_event(struct trace_event *event);
extern int unregister_trace_event(struct trace_event *event);

/* Return values for print_line callback */
enum print_line_t {
        TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
        TRACE_TYPE_HANDLED      = 1,
        TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
        TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
};

enum print_line_t trace_handle_return(struct trace_seq *s);

static inline void tracing_generic_entry_update(struct trace_entry *entry,
                                                unsigned short type,
                                                unsigned int trace_ctx)
{
        entry->preempt_count            = trace_ctx & 0xff;
        entry->pid                      = current->pid;
        entry->type                     = type;
        entry->flags =                  trace_ctx >> 16;
}

unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);

enum trace_flag_type {
        TRACE_FLAG_IRQS_OFF             = 0x01,
        TRACE_FLAG_NEED_RESCHED_LAZY    = 0x02,
        TRACE_FLAG_NEED_RESCHED         = 0x04,
        TRACE_FLAG_HARDIRQ              = 0x08,
        TRACE_FLAG_SOFTIRQ              = 0x10,
        TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
        TRACE_FLAG_NMI                  = 0x40,
        TRACE_FLAG_BH_OFF               = 0x80,
};

static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
{
        unsigned int irq_status = irqs_disabled_flags(irqflags) ?
                TRACE_FLAG_IRQS_OFF : 0;
        return tracing_gen_ctx_irq_test(irq_status);
}
static inline unsigned int tracing_gen_ctx(void)
{
        unsigned long irqflags;

        local_save_flags(irqflags);
        return tracing_gen_ctx_flags(irqflags);
}

static inline unsigned int tracing_gen_ctx_dec(void)
{
        unsigned int trace_ctx;

        trace_ctx = tracing_gen_ctx();
        /*
         * Subtract one from the preemption counter if preemption is enabled,
         * see trace_event_buffer_reserve()for details.
         */
        if (IS_ENABLED(CONFIG_PREEMPTION))
                trace_ctx--;
        return trace_ctx;
}

struct trace_event_file;

struct ring_buffer_event *
trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
                                struct trace_event_file *trace_file,
                                int type, unsigned long len,
                                unsigned int trace_ctx);

#define TRACE_RECORD_CMDLINE    BIT(0)
#define TRACE_RECORD_TGID       BIT(1)

void tracing_record_taskinfo(struct task_struct *task, int flags);
void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
                                          struct task_struct *next, int flags);

void tracing_record_cmdline(struct task_struct *task);
void tracing_record_tgid(struct task_struct *task);

int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
         __printf(3, 4);

struct event_filter;

enum trace_reg {
        TRACE_REG_REGISTER,
        TRACE_REG_UNREGISTER,
#ifdef CONFIG_PERF_EVENTS
        TRACE_REG_PERF_REGISTER,
        TRACE_REG_PERF_UNREGISTER,
        TRACE_REG_PERF_OPEN,
        TRACE_REG_PERF_CLOSE,
        /*
         * These (ADD/DEL) use a 'boolean' return value, where 1 (true) means a
         * custom action was taken and the default action is not to be
         * performed.
         */
        TRACE_REG_PERF_ADD,
        TRACE_REG_PERF_DEL,
#endif
};

struct trace_event_call;

#define TRACE_FUNCTION_TYPE ((const char *)~0UL)

struct trace_event_fields {
        const char *type;
        union {
                struct {
                        const char *name;
                        const int  size;
                        const int  align;
                        const unsigned int is_signed:1;
                        unsigned int needs_test:1;
                        const int  filter_type;
                        const int  len;
                };
                int (*define_fields)(struct trace_event_call *);
        };
};

struct trace_event_class {
        const char              *system;
        void                    *probe;
#ifdef CONFIG_PERF_EVENTS
        void                    *perf_probe;
#endif
        int                     (*reg)(struct trace_event_call *event,
                                       enum trace_reg type, void *data);
        struct trace_event_fields *fields_array;
        struct list_head        *(*get_fields)(struct trace_event_call *);
        struct list_head        fields;
        int                     (*raw_init)(struct trace_event_call *);
};

extern int trace_event_reg(struct trace_event_call *event,
                            enum trace_reg type, void *data);

struct trace_event_buffer {
        struct trace_buffer             *buffer;
        struct ring_buffer_event        *event;
        struct trace_event_file         *trace_file;
        void                            *entry;
        unsigned int                    trace_ctx;
        struct pt_regs                  *regs;
};

void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
                                  struct trace_event_file *trace_file,
                                  unsigned long len);

void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);

enum {
        TRACE_EVENT_FL_CAP_ANY_BIT,
        TRACE_EVENT_FL_NO_SET_FILTER_BIT,
        TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
        TRACE_EVENT_FL_TRACEPOINT_BIT,
        TRACE_EVENT_FL_DYNAMIC_BIT,
        TRACE_EVENT_FL_KPROBE_BIT,
        TRACE_EVENT_FL_UPROBE_BIT,
        TRACE_EVENT_FL_EPROBE_BIT,
        TRACE_EVENT_FL_FPROBE_BIT,
        TRACE_EVENT_FL_CUSTOM_BIT,
        TRACE_EVENT_FL_TEST_STR_BIT,
};

/*
 * Event flags:
 *  CAP_ANY       - Any user can enable for perf
 *  NO_SET_FILTER - Set when filter has error and is to be ignored
 *  IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
 *  TRACEPOINT    - Event is a tracepoint
 *  DYNAMIC       - Event is a dynamic event (created at run time)
 *  KPROBE        - Event is a kprobe
 *  UPROBE        - Event is a uprobe
 *  EPROBE        - Event is an event probe
 *  FPROBE        - Event is an function probe
 *  CUSTOM        - Event is a custom event (to be attached to an exsiting tracepoint)
 *                   This is set when the custom event has not been attached
 *                   to a tracepoint yet, then it is cleared when it is.
 *  TEST_STR      - The event has a "%s" that points to a string outside the event
 */
enum {
        TRACE_EVENT_FL_CAP_ANY          = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
        TRACE_EVENT_FL_NO_SET_FILTER    = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
        TRACE_EVENT_FL_IGNORE_ENABLE    = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
        TRACE_EVENT_FL_TRACEPOINT       = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
        TRACE_EVENT_FL_DYNAMIC          = (1 << TRACE_EVENT_FL_DYNAMIC_BIT),
        TRACE_EVENT_FL_KPROBE           = (1 << TRACE_EVENT_FL_KPROBE_BIT),
        TRACE_EVENT_FL_UPROBE           = (1 << TRACE_EVENT_FL_UPROBE_BIT),
        TRACE_EVENT_FL_EPROBE           = (1 << TRACE_EVENT_FL_EPROBE_BIT),
        TRACE_EVENT_FL_FPROBE           = (1 << TRACE_EVENT_FL_FPROBE_BIT),
        TRACE_EVENT_FL_CUSTOM           = (1 << TRACE_EVENT_FL_CUSTOM_BIT),
        TRACE_EVENT_FL_TEST_STR         = (1 << TRACE_EVENT_FL_TEST_STR_BIT),
};

#define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)

struct trace_event_call {
        struct list_head        list;
        struct trace_event_class *class;
        union {
                const char              *name;
                /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
                struct tracepoint       *tp;
        };
        struct trace_event      event;
        char                    *print_fmt;
        /*
         * Static events can disappear with modules,
         * where as dynamic ones need their own ref count.
         */
        union {
                void                            *module;
                atomic_t                        refcnt;
        };
        void                    *data;

        /* See the TRACE_EVENT_FL_* flags above */
        int                     flags; /* static flags of different events */

#ifdef CONFIG_PERF_EVENTS
        int                             perf_refcount;
        struct hlist_head __percpu      *perf_events;
        struct bpf_prog_array __rcu     *prog_array;

        int     (*perf_perm)(struct trace_event_call *,
                             struct perf_event *);
#endif
};

#ifdef CONFIG_DYNAMIC_EVENTS
bool trace_event_dyn_try_get_ref(struct trace_event_call *call);
void trace_event_dyn_put_ref(struct trace_event_call *call);
bool trace_event_dyn_busy(struct trace_event_call *call);
#else
static inline bool trace_event_dyn_try_get_ref(struct trace_event_call *call)
{
        /* Without DYNAMIC_EVENTS configured, nothing should be calling this */
        return false;
}
static inline void trace_event_dyn_put_ref(struct trace_event_call *call)
{
}
static inline bool trace_event_dyn_busy(struct trace_event_call *call)
{
        /* Nothing should call this without DYNAIMIC_EVENTS configured. */
        return true;
}
#endif

static inline bool trace_event_try_get_ref(struct trace_event_call *call)
{
        if (call->flags & TRACE_EVENT_FL_DYNAMIC)
                return trace_event_dyn_try_get_ref(call);
        else
                return try_module_get(call->module);
}

static inline void trace_event_put_ref(struct trace_event_call *call)
{
        if (call->flags & TRACE_EVENT_FL_DYNAMIC)
                trace_event_dyn_put_ref(call);
        else
                module_put(call->module);
}

#ifdef CONFIG_PERF_EVENTS
static inline bool bpf_prog_array_valid(struct trace_event_call *call)
{
        /*
         * This inline function checks whether call->prog_array
         * is valid or not. The function is called in various places,
         * outside rcu_read_lock/unlock, as a heuristic to speed up execution.
         *
         * If this function returns true, and later call->prog_array
         * becomes false inside rcu_read_lock/unlock region,
         * we bail out then. If this function return false,
         * there is a risk that we might miss a few events if the checking
         * were delayed until inside rcu_read_lock/unlock region and
         * call->prog_array happened to become non-NULL then.
         *
         * Here, READ_ONCE() is used instead of rcu_access_pointer().
         * rcu_access_pointer() requires the actual definition of
         * "struct bpf_prog_array" while READ_ONCE() only needs
         * a declaration of the same type.
         */
        return !!READ_ONCE(call->prog_array);
}
#endif

static inline const char *
trace_event_name(struct trace_event_call *call)
{
        if (call->flags & TRACE_EVENT_FL_CUSTOM)
                return call->name;
        else if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
                return call->tp ? call->tp->name : NULL;
        else
                return call->name;
}

static inline struct list_head *
trace_get_fields(struct trace_event_call *event_call)
{
        if (!event_call->class->get_fields)
                return &event_call->class->fields;
        return event_call->class->get_fields(event_call);
}

struct trace_subsystem_dir;

enum {
        EVENT_FILE_FL_ENABLED_BIT,
        EVENT_FILE_FL_RECORDED_CMD_BIT,
        EVENT_FILE_FL_RECORDED_TGID_BIT,
        EVENT_FILE_FL_FILTERED_BIT,
        EVENT_FILE_FL_NO_SET_FILTER_BIT,
        EVENT_FILE_FL_SOFT_DISABLED_BIT,
        EVENT_FILE_FL_TRIGGER_MODE_BIT,
        EVENT_FILE_FL_TRIGGER_COND_BIT,
        EVENT_FILE_FL_PID_FILTER_BIT,
        EVENT_FILE_FL_WAS_ENABLED_BIT,
        EVENT_FILE_FL_FREED_BIT,
};

extern struct trace_event_file *trace_get_event_file(const char *instance,
                                                     const char *system,
                                                     const char *event);
extern void trace_put_event_file(struct trace_event_file *file);

#define MAX_DYNEVENT_CMD_LEN    (2048)

enum dynevent_type {
        DYNEVENT_TYPE_SYNTH = 1,
        DYNEVENT_TYPE_KPROBE,
        DYNEVENT_TYPE_NONE,
};

struct dynevent_cmd;

typedef int (*dynevent_create_fn_t)(struct dynevent_cmd *cmd);

struct dynevent_cmd {
        struct seq_buf          seq;
        const char              *event_name;
        unsigned int            n_fields;
        enum dynevent_type      type;
        dynevent_create_fn_t    run_command;
        void                    *private_data;
};

extern int dynevent_create(struct dynevent_cmd *cmd);

extern int synth_event_delete(const char *name);

extern void synth_event_cmd_init(struct dynevent_cmd *cmd,
                                 char *buf, int maxlen);

extern int __synth_event_gen_cmd_start(struct dynevent_cmd *cmd,
                                       const char *name,
                                       struct module *mod, ...);

#define synth_event_gen_cmd_start(cmd, name, mod, ...)  \
        __synth_event_gen_cmd_start(cmd, name, mod, ## __VA_ARGS__, NULL)

struct synth_field_desc {
        const char *type;
        const char *name;
};

extern int synth_event_gen_cmd_array_start(struct dynevent_cmd *cmd,
                                           const char *name,
                                           struct module *mod,
                                           struct synth_field_desc *fields,
                                           unsigned int n_fields);
extern int synth_event_create(const char *name,
                              struct synth_field_desc *fields,
                              unsigned int n_fields, struct module *mod);

extern int synth_event_add_field(struct dynevent_cmd *cmd,
                                 const char *type,
                                 const char *name);
extern int synth_event_add_field_str(struct dynevent_cmd *cmd,
                                     const char *type_name);
extern int synth_event_add_fields(struct dynevent_cmd *cmd,
                                  struct synth_field_desc *fields,
                                  unsigned int n_fields);

#define synth_event_gen_cmd_end(cmd)    \
        dynevent_create(cmd)

struct synth_event;

struct synth_event_trace_state {
        struct trace_event_buffer fbuffer;
        struct synth_trace_event *entry;
        struct trace_buffer *buffer;
        struct synth_event *event;
        unsigned int cur_field;
        unsigned int n_u64;
        bool disabled;
        bool add_next;
        bool add_name;
};

extern int synth_event_trace(struct trace_event_file *file,
                             unsigned int n_vals, ...);
extern int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
                                   unsigned int n_vals);
extern int synth_event_trace_start(struct trace_event_file *file,
                                   struct synth_event_trace_state *trace_state);
extern int synth_event_add_next_val(u64 val,
                                    struct synth_event_trace_state *trace_state);
extern int synth_event_add_val(const char *field_name, u64 val,
                               struct synth_event_trace_state *trace_state);
extern int synth_event_trace_end(struct synth_event_trace_state *trace_state);

extern int kprobe_event_delete(const char *name);

extern void kprobe_event_cmd_init(struct dynevent_cmd *cmd,
                                  char *buf, int maxlen);

#define kprobe_event_gen_cmd_start(cmd, name, loc, ...)                 \
        __kprobe_event_gen_cmd_start(cmd, false, name, loc, ## __VA_ARGS__, NULL)

#define kretprobe_event_gen_cmd_start(cmd, name, loc, ...)              \
        __kprobe_event_gen_cmd_start(cmd, true, name, loc, ## __VA_ARGS__, NULL)

extern int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd,
                                        bool kretprobe,
                                        const char *name,
                                        const char *loc, ...);

#define kprobe_event_add_fields(cmd, ...)       \
        __kprobe_event_add_fields(cmd, ## __VA_ARGS__, NULL)

#define kprobe_event_add_field(cmd, field)      \
        __kprobe_event_add_fields(cmd, field, NULL)

extern int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...);

#define kprobe_event_gen_cmd_end(cmd)           \
        dynevent_create(cmd)

#define kretprobe_event_gen_cmd_end(cmd)        \
        dynevent_create(cmd)

/*
 * Event file flags:
 *  ENABLED       - The event is enabled
 *  RECORDED_CMD  - The comms should be recorded at sched_switch
 *  RECORDED_TGID - The tgids should be recorded at sched_switch
 *  FILTERED      - The event has a filter attached
 *  NO_SET_FILTER - Set when filter has error and is to be ignored
 *  SOFT_DISABLED - When set, do not trace the event (even though its
 *                   tracepoint may be enabled)
 *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
 *  TRIGGER_COND  - When set, one or more triggers has an associated filter
 *  PID_FILTER    - When set, the event is filtered based on pid
 *  WAS_ENABLED   - Set when enabled to know to clear trace on module removal
 *  FREED         - File descriptor is freed, all fields should be considered invalid
 */
enum {
        EVENT_FILE_FL_ENABLED           = (1 << EVENT_FILE_FL_ENABLED_BIT),
        EVENT_FILE_FL_RECORDED_CMD      = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
        EVENT_FILE_FL_RECORDED_TGID     = (1 << EVENT_FILE_FL_RECORDED_TGID_BIT),
        EVENT_FILE_FL_FILTERED          = (1 << EVENT_FILE_FL_FILTERED_BIT),
        EVENT_FILE_FL_NO_SET_FILTER     = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
        EVENT_FILE_FL_SOFT_DISABLED     = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
        EVENT_FILE_FL_TRIGGER_MODE      = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
        EVENT_FILE_FL_TRIGGER_COND      = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
        EVENT_FILE_FL_PID_FILTER        = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
        EVENT_FILE_FL_WAS_ENABLED       = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT),
        EVENT_FILE_FL_FREED             = (1 << EVENT_FILE_FL_FREED_BIT),
};

struct trace_event_file {
        struct list_head                list;
        struct trace_event_call         *event_call;
        struct event_filter __rcu       *filter;
        struct eventfs_inode            *ei;
        struct trace_array              *tr;
        struct trace_subsystem_dir      *system;
        struct list_head                triggers;

        /*
         * 32 bit flags:
         *   bit 0:             enabled
         *   bit 1:             enabled cmd record
         *   bit 2:             enable/disable with the soft disable bit
         *   bit 3:             soft disabled
         *   bit 4:             trigger enabled
         *
         * Note: The bits must be set atomically to prevent races
         * from other writers. Reads of flags do not need to be in
         * sync as they occur in critical sections. But the way flags
         * is currently used, these changes do not affect the code
         * except that when a change is made, it may have a slight
         * delay in propagating the changes to other CPUs due to
         * caching and such. Which is mostly OK ;-)
         */
        unsigned long           flags;
        refcount_t              ref;    /* ref count for opened files */
        atomic_t                sm_ref; /* soft-mode reference counter */
        atomic_t                tm_ref; /* trigger-mode reference counter */
};

#ifdef CONFIG_HIST_TRIGGERS
extern struct irq_work hist_poll_work;
extern wait_queue_head_t hist_poll_wq;

static inline void hist_poll_wakeup(void)
{
        if (wq_has_sleeper(&hist_poll_wq))
                irq_work_queue(&hist_poll_work);
}

#define hist_poll_wait(file, wait)      \
        poll_wait(file, &hist_poll_wq, wait)

#else
static inline void hist_poll_wakeup(void)
{
}
#endif

#define __TRACE_EVENT_FLAGS(name, value)                                \
        static int __init trace_init_flags_##name(void)                 \
        {                                                               \
                event_##name.flags |= value;                            \
                return 0;                                               \
        }                                                               \
        early_initcall(trace_init_flags_##name);

#define __TRACE_EVENT_PERF_PERM(name, expr...)                          \
        static int perf_perm_##name(struct trace_event_call *tp_event, \
                                    struct perf_event *p_event)         \
        {                                                               \
                return ({ expr; });                                     \
        }                                                               \
        static int __init trace_init_perf_perm_##name(void)             \
        {                                                               \
                event_##name.perf_perm = &perf_perm_##name;             \
                return 0;                                               \
        }                                                               \
        early_initcall(trace_init_perf_perm_##name);

#define PERF_MAX_TRACE_SIZE     8192

#define MAX_FILTER_STR_VAL      256U    /* Should handle KSYM_SYMBOL_LEN */

enum event_trigger_type {
        ETT_NONE                = (0),
        ETT_TRACE_ONOFF         = (1 << 0),
        ETT_SNAPSHOT            = (1 << 1),
        ETT_STACKTRACE          = (1 << 2),
        ETT_EVENT_ENABLE        = (1 << 3),
        ETT_EVENT_HIST          = (1 << 4),
        ETT_HIST_ENABLE         = (1 << 5),
        ETT_EVENT_EPROBE        = (1 << 6),
};

extern int filter_match_preds(struct event_filter *filter, void *rec);

extern enum event_trigger_type
event_triggers_call(struct trace_event_file *file,
                    struct trace_buffer *buffer, void *rec,
                    struct ring_buffer_event *event);
extern void
event_triggers_post_call(struct trace_event_file *file,
                         enum event_trigger_type tt);

bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);

bool __trace_trigger_soft_disabled(struct trace_event_file *file);

/**
 * trace_trigger_soft_disabled - do triggers and test if soft disabled
 * @file: The file pointer of the event to test
 *
 * If any triggers without filters are attached to this event, they
 * will be called here. If the event is soft disabled and has no
 * triggers that require testing the fields, it will return true,
 * otherwise false.
 */
static __always_inline bool
trace_trigger_soft_disabled(struct trace_event_file *file)
{
        unsigned long eflags = file->flags;

        if (likely(!(eflags & (EVENT_FILE_FL_TRIGGER_MODE |
                               EVENT_FILE_FL_SOFT_DISABLED |
                               EVENT_FILE_FL_PID_FILTER))))
                return false;

        if (likely(eflags & EVENT_FILE_FL_TRIGGER_COND))
                return false;

        return __trace_trigger_soft_disabled(file);
}

#ifdef CONFIG_BPF_EVENTS
unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx);
int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
void perf_event_detach_bpf_prog(struct perf_event *event);
int perf_event_query_prog_array(struct perf_event *event, void __user *info);

struct bpf_raw_tp_link;
int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);

struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name);
void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp);
int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
                            u32 *fd_type, const char **buf,
                            u64 *probe_offset, u64 *probe_addr,
                            unsigned long *missed);
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
#else
static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
{
        return 1;
}

static inline int
perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie)
{
        return -EOPNOTSUPP;
}

static inline void perf_event_detach_bpf_prog(struct perf_event *event) { }

static inline int
perf_event_query_prog_array(struct perf_event *event, void __user *info)
{
        return -EOPNOTSUPP;
}
struct bpf_raw_tp_link;
static inline int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
{
        return -EOPNOTSUPP;
}
static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
{
        return -EOPNOTSUPP;
}
static inline struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
{
        return NULL;
}
static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
{
}
static inline int bpf_get_perf_event_info(const struct perf_event *event,
                                          u32 *prog_id, u32 *fd_type,
                                          const char **buf, u64 *probe_offset,
                                          u64 *probe_addr, unsigned long *missed)
{
        return -EOPNOTSUPP;
}
static inline int
bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
        return -EOPNOTSUPP;
}
static inline int
bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
        return -EOPNOTSUPP;
}
#endif

enum {
        FILTER_OTHER = 0,
        FILTER_STATIC_STRING,
        FILTER_DYN_STRING,
        FILTER_RDYN_STRING,
        FILTER_PTR_STRING,
        FILTER_TRACE_FN,
        FILTER_CPUMASK,
        FILTER_COMM,
        FILTER_CPU,
        FILTER_STACKTRACE,
};

extern int trace_event_raw_init(struct trace_event_call *call);
extern int trace_define_field(struct trace_event_call *call, const char *type,
                              const char *name, int offset, int size,
                              int is_signed, int filter_type);
extern int trace_add_event_call(struct trace_event_call *call);
extern int trace_remove_event_call(struct trace_event_call *call);
extern int trace_event_get_offsets(struct trace_event_call *call);

int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
int trace_set_clr_event(const char *system, const char *event, int set);
int trace_array_set_clr_event(struct trace_array *tr, const char *system,
                const char *event, bool enable);

#ifdef CONFIG_PERF_EVENTS
struct perf_event;

DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);

extern int  perf_trace_init(struct perf_event *event);
extern void perf_trace_destroy(struct perf_event *event);
extern int  perf_trace_add(struct perf_event *event, int flags);
extern void perf_trace_del(struct perf_event *event, int flags);
#ifdef CONFIG_KPROBE_EVENTS
extern int  perf_kprobe_init(struct perf_event *event, bool is_retprobe);
extern void perf_kprobe_destroy(struct perf_event *event);
extern int bpf_get_kprobe_info(const struct perf_event *event,
                               u32 *fd_type, const char **symbol,
                               u64 *probe_offset, u64 *probe_addr,
                               unsigned long *missed,
                               bool perf_type_tracepoint);
#endif
#ifdef CONFIG_UPROBE_EVENTS
extern int  perf_uprobe_init(struct perf_event *event,
                             unsigned long ref_ctr_offset, bool is_retprobe);
extern void perf_uprobe_destroy(struct perf_event *event);
extern int bpf_get_uprobe_info(const struct perf_event *event,
                               u32 *fd_type, const char **filename,
                               u64 *probe_offset, u64 *probe_addr,
                               bool perf_type_tracepoint);
#endif
extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
                                     char *filter_str);
extern void ftrace_profile_free_filter(struct perf_event *event);
void perf_trace_buf_update(void *record, u16 type);
void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp);

int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
void perf_event_free_bpf_prog(struct perf_event *event);

void bpf_trace_run1(struct bpf_raw_tp_link *link, u64 arg1);
void bpf_trace_run2(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2);
void bpf_trace_run3(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3);
void bpf_trace_run4(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4);
void bpf_trace_run5(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4, u64 arg5);
void bpf_trace_run6(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4, u64 arg5, u64 arg6);
void bpf_trace_run7(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7);
void bpf_trace_run8(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
                    u64 arg8);
void bpf_trace_run9(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
                    u64 arg8, u64 arg9);
void bpf_trace_run10(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
                     u64 arg8, u64 arg9, u64 arg10);
void bpf_trace_run11(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
                     u64 arg8, u64 arg9, u64 arg10, u64 arg11);
void bpf_trace_run12(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
                     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
                     u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12);
void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
                               struct trace_event_call *call, u64 count,
                               struct pt_regs *regs, struct hlist_head *head,
                               struct task_struct *task);

static inline void
perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type,
                       u64 count, struct pt_regs *regs, void *head,
                       struct task_struct *task)
{
        perf_tp_event(type, count, raw_data, size, regs, head, rctx, task);
}

#endif

#define TRACE_EVENT_STR_MAX     512

/*
 * gcc warns that you can not use a va_list in an inlined
 * function. But lets me make it into a macro :-/
 */
#define __trace_event_vstr_len(fmt, va)                 \
({                                                      \
        va_list __ap;                                   \
        int __ret;                                      \
                                                        \
        va_copy(__ap, *(va));                           \
        __ret = vsnprintf(NULL, 0, fmt, __ap) + 1;      \
        va_end(__ap);                                   \
                                                        \
        min(__ret, TRACE_EVENT_STR_MAX);                \
})

#endif /* _LINUX_TRACE_EVENT_H */

/*
 * Note: we keep the TRACE_CUSTOM_EVENT outside the include file ifdef protection.
 *  This is due to the way trace custom events work. If a file includes two
 *  trace event headers under one "CREATE_CUSTOM_TRACE_EVENTS" the first include
 *  will override the TRACE_CUSTOM_EVENT and break the second include.
 */

#ifndef TRACE_CUSTOM_EVENT

#define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print)
#define DEFINE_CUSTOM_EVENT(template, name, proto, args)
#define TRACE_CUSTOM_EVENT(name, proto, args, struct, assign, print)

#endif /* ifdef TRACE_CUSTOM_EVENT (see note above) */