wrapper/tracepoint.h

   1 #ifndef _LTTNG_WRAPPER_TRACEPOINT_H
   2 #define _LTTNG_WRAPPER_TRACEPOINT_H
   3
   4 /*
   5  * wrapper/tracepoint.h
   6  *
   7  * wrapper around DECLARE_EVENT_CLASS.
   8  *
   9  * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; only
  14  * version 2.1 of the License.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  24  */
  25
  26 #include <linux/version.h>
  27 #include <linux/tracepoint.h>
  28 #include <linux/module.h>
  29
  30 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,35))
  31
  32 #define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print)
  33
  34 #endif
  35
  36 #ifndef HAVE_KABI_2635_TRACEPOINT
  37
  38 #define kabi_2635_tracepoint_probe_register tracepoint_probe_register
  39 #define kabi_2635_tracepoint_probe_unregister tracepoint_probe_unregister
  40 #define kabi_2635_tracepoint_probe_register_noupdate tracepoint_probe_register_noupdate
  41 #define kabi_2635_tracepoint_probe_unregister_noupdate tracepoint_probe_unregister_noupdate
  42
  43 #endif /* HAVE_KABI_2635_TRACEPOINT */
  44
  45 #ifdef CONFIG_MODULE_SIG
  46
  47 #include <linux/kallsyms.h>
  48 #include "kallsyms.h"
  49
  50 static inline
  51 int wrapper_tracepoint_module_notify(struct notifier_block *nb,
  52                 unsigned long val, struct module *mod)
  53 {
  54         int (*tracepoint_module_notify_sym)(struct notifier_block *nb,
  55                         unsigned long val, struct module *mod);
  56
  57         tracepoint_module_notify_sym =
  58                 (void *) kallsyms_lookup_funcptr("tracepoint_module_notify");
  59         if (tracepoint_module_notify_sym) {
  60                 return tracepoint_module_notify_sym(nb, val, mod);
  61         } else {
  62                 printk(KERN_WARNING "LTTng: tracepoint_module_notify symbol lookup failed.\n");
  63                 return -ENOSYS;
  64         }
  65 }
  66
  67 static inline
  68 int wrapper_lttng_fixup_sig(struct module *mod)
  69 {
  70         int ret = 0;
  71
  72         /*
  73          * This is for module.c confusing force loaded modules with
  74          * unsigned modules.
  75          */
  76         if (!THIS_MODULE->sig_ok &&
  77                         THIS_MODULE->taints & (1U << TAINT_FORCED_MODULE)) {
  78                 THIS_MODULE->taints &= ~(1U << TAINT_FORCED_MODULE);
  79                 ret = wrapper_tracepoint_module_notify(NULL,
  80                                 MODULE_STATE_COMING, mod);
  81                 THIS_MODULE->taints |= (1U << TAINT_FORCED_MODULE);
  82         }
  83         return ret;
  84 }
  85
  86 #else /* CONFIG_MODULE_SIG */
  87
  88 static inline
  89 int wrapper_lttng_fixup_sig(struct module *mod)
  90 {
  91         return 0;
  92 }
  93
  94 #endif /* #else CONFIG_MODULE_SIG */
  95
  96 #endif /* _LTTNG_WRAPPER_TRACEPOINT_H */