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// SPDX-License-Identifier: GPL-2.0-only
#include <linux/module.h>
#include <linux/mm.h> /* for handle_mm_fault() */
#include <linux/ftrace.h>
#include <linux/sched/stat.h>
extern void my_direct_func(unsigned long ip);
void my_direct_func(unsigned long ip)
{
trace_printk("ip %lx\n", ip);
}
extern void my_tramp(void *);
asm (
" .pushsection .text, \"ax\", @progbits\n"
" .type my_tramp, @function\n"
" .globl my_tramp\n"
" my_tramp:"
" pushq %rbp\n"
" movq %rsp, %rbp\n"
" pushq %rdi\n"
" movq 8(%rbp), %rdi\n"
" call my_direct_func\n"
" popq %rdi\n"
" leave\n"
" ret\n"
" .size my_tramp, .-my_tramp\n"
" .popsection\n"
);
static struct ftrace_ops direct;
static int __init ftrace_direct_multi_init(void)
{
ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0);
return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
}
static void __exit ftrace_direct_multi_exit(void)
{
unregister_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
}
module_init(ftrace_direct_multi_init);
module_exit(ftrace_direct_multi_exit);
MODULE_AUTHOR("Jiri Olsa");
MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()");
MODULE_LICENSE("GPL");
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