1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
3 * lttng-syscalls-extractor.c
5 * Dump syscall metadata to console.
7 * Copyright 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 * Copyright 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/list.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/kallsyms.h>
18 #include <linux/dcache.h>
19 #include <linux/trace_events.h>
20 #include <trace/syscall.h>
21 #include <asm/syscall.h>
23 #ifndef CONFIG_FTRACE_SYSCALLS
24 #error "You need to set CONFIG_FTRACE_SYSCALLS=y"
27 #ifndef CONFIG_KALLSYMS_ALL
28 #error "You need to set CONFIG_KALLSYMS_ALL=y"
32 * The 'ident' parameter is prepended to each printk line to help
33 * extract the proper lines from dmesg.
35 static char *ident
= "";
36 module_param(ident
, charp
, 0);
38 static struct syscall_metadata
**__start_syscalls_metadata
;
39 static struct syscall_metadata
**__stop_syscalls_metadata
;
42 struct syscall_metadata
*find_syscall_meta(unsigned long syscall
)
44 struct syscall_metadata
**iter
;
46 for (iter
= __start_syscalls_metadata
;
47 iter
< __stop_syscalls_metadata
; iter
++) {
48 if ((*iter
)->syscall_nr
== syscall
)
56 struct syscall_metadata
*meta
;
59 __start_syscalls_metadata
= (void *) kallsyms_lookup_name("__start_syscalls_metadata");
60 __stop_syscalls_metadata
= (void *) kallsyms_lookup_name("__stop_syscalls_metadata");
62 printk("%s---START---\n", ident
);
63 for (i
= 0; i
< NR_syscalls
; i
++) {
66 meta
= find_syscall_meta(i
);
69 printk("%ssyscall %s nr %d nbargs %d ",
70 ident
, meta
->name
, meta
->syscall_nr
, meta
->nb_args
);
71 printk(KERN_CONT
"types: (");
72 for (j
= 0; j
< meta
->nb_args
; j
++) {
74 printk(KERN_CONT
", ");
75 printk(KERN_CONT
"%s", meta
->types
[j
]);
77 printk(KERN_CONT
") ");
78 printk(KERN_CONT
"args: (");
79 for (j
= 0; j
< meta
->nb_args
; j
++) {
81 printk(KERN_CONT
", ");
82 printk(KERN_CONT
"%s", meta
->args
[j
]);
84 printk(KERN_CONT
")\n");
86 printk("%s---END---\n", ident
);
89 * This module always fails to load.
94 void cleanup_module(void)
98 MODULE_LICENSE("GPL");