linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Kprobes-based tracing events

 *

 * Created by Masami Hiramatsu <mhiramat@redhat.com>

 *

 */

#define pr_fmt(fmt) "trace_kprobe: " fmt

​

#include <linux/module.h>

#include <linux/uaccess.h>

#include <linux/rculist.h>

#include <linux/error-injection.h>

​

#include "trace_dynevent.h"

#include "trace_kprobe_selftest.h"

#include "trace_probe.h"

#include "trace_probe_tmpl.h"

​

#define KPROBE_EVENT_SYSTEM "kprobes"

#define KRETPROBE_MAXACTIVE_MAX 4096

​

static int trace_kprobe_create(int argc, const char **argv);

static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);

static int trace_kprobe_release(struct dyn_event *ev);

static bool trace_kprobe_is_busy(struct dyn_event *ev);

static bool trace_kprobe_match(const char *system, const char *event,

                   struct dyn_event *ev);

​

static struct dyn_event_operations trace_kprobe_ops = {

    .create = trace_kprobe_create,

    .show = trace_kprobe_show,

    .is_busy = trace_kprobe_is_busy,

    .free = trace_kprobe_release,

    .match = trace_kprobe_match,

};

​

/*

 * Kprobe event core functions

 */

struct trace_kprobe {

    struct dyn_event    devent;

    struct kretprobe    rp; /* Use rp.kp for kprobe use */

    unsigned long __percpu *nhit;

    const char      *symbol;    /* symbol name */

    struct trace_probe  tp;

};

​

static bool is_trace_kprobe(struct dyn_event *ev)

{

    return ev->ops == &trace_kprobe_ops;

}

​

static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev)

{

    return container_of(ev, struct trace_kprobe, devent);

}

​

/**

 * for_each_trace_kprobe - iterate over the trace_kprobe list

 * @pos:    the struct trace_kprobe * for each entry

 * @dpos:   the struct dyn_event * to use as a loop cursor

 */