instrumentation/syscalls/lttng-syscalls-extractor/lttng-syscalls-extractor.c

   1 /*
   2  * lttng-syscalls-extractor.c
   3  *
   4  * Dump syscall metadata to console.
   5  *
   6  * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  * Copyright 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/types.h>
  27 #include <linux/list.h>
  28 #include <linux/err.h>
  29 #include <linux/slab.h>
  30 #include <linux/kallsyms.h>
  31 #include <linux/dcache.h>
  32 #include <linux/ftrace_event.h>
  33 #include <trace/syscall.h>
  34 #include <asm/syscall.h>
  35
  36 #ifndef CONFIG_FTRACE_SYSCALLS
  37 #error "You need to set CONFIG_FTRACE_SYSCALLS=y"
  38 #endif
  39
  40 #ifndef CONFIG_KALLSYMS_ALL
  41 #error "You need to set CONFIG_KALLSYMS_ALL=y"
  42 #endif
  43
  44 static struct syscall_metadata **__start_syscalls_metadata;
  45 static struct syscall_metadata **__stop_syscalls_metadata;
  46
  47 static __init
  48 struct syscall_metadata *find_syscall_meta(unsigned long syscall)
  49 {
  50         struct syscall_metadata **iter;
  51
  52         for (iter = __start_syscalls_metadata;
  53                         iter < __stop_syscalls_metadata; iter++) {
  54                 if ((*iter)->syscall_nr == syscall)
  55                         return (*iter);
  56         }
  57         return NULL;
  58 }
  59
  60 int init_module(void)
  61 {
  62         struct syscall_metadata *meta;
  63         int i;
  64
  65         __start_syscalls_metadata = (void *) kallsyms_lookup_name("__start_syscalls_metadata");
  66         __stop_syscalls_metadata = (void *) kallsyms_lookup_name("__stop_syscalls_metadata");
  67
  68         for (i = 0; i < NR_syscalls; i++) {
  69                 int j;
  70
  71                 meta = find_syscall_meta(i);
  72                 if (!meta)
  73                         continue;
  74                 printk("syscall %s nr %d nbargs %d ",
  75                         meta->name, meta->syscall_nr, meta->nb_args);
  76                 printk("types: (");
  77                 for (j = 0; j < meta->nb_args; j++) {
  78                         if (j > 0)
  79                                 printk(", ");
  80                         printk("%s", meta->types[j]);
  81                 }
  82                 printk(") ");
  83                 printk("args: (");
  84                 for (j = 0; j < meta->nb_args; j++) {
  85                         if (j > 0)
  86                                 printk(", ");
  87                         printk("%s", meta->args[j]);
  88                 }
  89                 printk(")\n");
  90         }
  91         printk("SUCCESS\n");
  92
  93         return -1;
  94 }
  95
  96 void cleanup_module(void)
  97 {
  98 }
  99
 100 MODULE_LICENSE("GPL");