-#ifndef _LTTNG_TRACEPOINT_H
-#define _LTTNG_TRACEPOINT_H
-
/*
- * Copyright 2011-2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*/
+#ifndef _LTTNG_TRACEPOINT_H
+#define _LTTNG_TRACEPOINT_H
+
#include <stdio.h>
#include <stdlib.h>
#include <lttng/tracepoint-types.h>
#include <urcu/system.h>
#include <dlfcn.h> /* for dlopen */
#include <string.h> /* for memset */
+
#include <lttng/ust-config.h> /* for sdt */
#include <lttng/ust-compiler.h>
+#include <lttng/ust-tracer.h>
#ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
-#define SDT_USE_VARIADIC
+/*
+ * Instead of using SDT_USE_VARIADIC from 'sys/sdt.h', use our own namespaced
+ * macros since the instrumented application might already have included
+ * 'sys/sdt.h' without variadic support.
+ */
#include <sys/sdt.h>
-#define LTTNG_STAP_PROBEV STAP_PROBEV
+
+#define _LTTNG_SDT_NARG(...) \
+ __LTTNG_SDT_NARG(__VA_ARGS__, 12,11,10,9,8,7,6,5,4,3,2,1,0)
+
+#define __LTTNG_SDT_NARG(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12, N, ...) N
+
+#define _LTTNG_SDT_PROBE_N(provider, name, N, ...) \
+ _SDT_PROBE(provider, name, N, (__VA_ARGS__))
+
+#define LTTNG_STAP_PROBEV(provider, name, ...) \
+ _LTTNG_SDT_PROBE_N(provider, name, _LTTNG_SDT_NARG(0, ##__VA_ARGS__), ##__VA_ARGS__)
+
#else
#define LTTNG_STAP_PROBEV(...)
#endif
*/
#define _DECLARE_TRACEPOINT(_provider, _name, ...) \
extern struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name; \
-static inline __attribute__((always_inline, unused)) lttng_ust_notrace \
-void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)); \
+static inline \
+void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
+ __attribute__((always_inline, unused)) lttng_ust_notrace; \
static \
void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
{ \
- struct lttng_ust_tracepoint_probe *__tp_probe; \
+ struct lttng_ust_tracepoint_probe *__tp_probe; \
\
if (caa_unlikely(!TP_RCU_LINK_TEST())) \
return; \
- tp_rcu_read_lock_bp(); \
- __tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \
+ tp_rcu_read_lock(); \
+ __tp_probe = tp_rcu_dereference(__tracepoint_##_provider##___##_name.probes); \
if (caa_unlikely(!__tp_probe)) \
goto end; \
do { \
(_TP_ARGS_DATA_VAR(__VA_ARGS__)); \
} while ((++__tp_probe)->func); \
end: \
- tp_rcu_read_unlock_bp(); \
+ tp_rcu_read_unlock(); \
} \
static inline lttng_ust_notrace \
void __tracepoint_register_##_provider##___##_name(char *name, \
/*
* tracepoint dynamic linkage handling (callbacks). Hidden visibility:
* shared across objects in a module/main executable.
+ *
+ * IMPORTANT: this structure is part of the ABI between instrumented
+ * applications and UST. Fields need to be only added at the end, never
+ * reordered, never removed.
+ *
+ * The field @struct_size should be used to determine the size of the
+ * structure. It should be queried before using additional fields added
+ * at the end of the structure.
*/
struct lttng_ust_tracepoint_dlopen {
+ uint32_t struct_size;
+
void *liblttngust_handle;
int (*tracepoint_register_lib)(struct lttng_ust_tracepoint * const *tracepoints_start,
int tracepoints_count);
int (*tracepoint_unregister_lib)(struct lttng_ust_tracepoint * const *tracepoints_start);
- void (*rcu_read_lock_sym_bp)(void);
- void (*rcu_read_unlock_sym_bp)(void);
- void *(*rcu_dereference_sym_bp)(void *p);
+ void (*rcu_read_lock_sym)(void);
+ void (*rcu_read_unlock_sym)(void);
+ void *(*rcu_dereference_sym)(void *p);
+
+ /* End of base ABI. Fields below should be used after checking struct_size. */
};
extern struct lttng_ust_tracepoint_dlopen tracepoint_dlopen;
int __tracepoint_ptrs_registered
__attribute__((weak, visibility("hidden")));
struct lttng_ust_tracepoint_dlopen tracepoint_dlopen
- __attribute__((weak, visibility("hidden")));
+ __attribute__((weak, visibility("hidden"))) = {
+ .struct_size = sizeof(struct lttng_ust_tracepoint_dlopen),
+};
/*
* Deal with gcc O1 optimisation issues with weak hidden symbols. gcc
* 4.8 and prior does not have the same behavior for symbol scoping on
* Tracepoint dynamic linkage handling (callbacks). Hidden visibility: shared
* across objects in a module/main executable. The callbacks are used to
* control and check if the destructors should be executed.
+ *
+ * IMPORTANT: this structure is part of the ABI between instrumented
+ * applications and UST. Fields need to be only added at the end, never
+ * reordered, never removed.
+ *
+ * The field @struct_size should be used to determine the size of the
+ * structure. It should be queried before using additional fields added
+ * at the end of the structure.
*/
struct lttng_ust_tracepoint_destructors_syms {
- int *old_tracepoint_disable_destructors;
+ uint32_t struct_size;
+
void (*tracepoint_disable_destructors)(void);
int (*tracepoint_get_destructors_state)(void);
+
+ /* End of base ABI. Fields below should be used after checking struct_size. */
};
extern struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms;
extern struct lttng_ust_tracepoint_destructors_syms *tracepoint_destructors_syms_ptr;
struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms
- __attribute__((weak, visibility("hidden")));
+ __attribute__((weak, visibility("hidden"))) = {
+ .struct_size = sizeof(struct lttng_ust_tracepoint_destructors_syms),
+};
struct lttng_ust_tracepoint_destructors_syms *tracepoint_destructors_syms_ptr
__attribute__((weak, visibility("hidden")));
if (tracepoint_dlopen_ptr->liblttngust_handle
&& tracepoint_destructors_syms_ptr->tracepoint_disable_destructors)
tracepoint_destructors_syms_ptr->tracepoint_disable_destructors();
- *tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors = 1;
}
#ifndef _LGPL_SOURCE
* Symbols below are needed by tracepoint call sites and probe
* providers.
*/
- if (!tracepoint_dlopen_ptr->rcu_read_lock_sym_bp)
- tracepoint_dlopen_ptr->rcu_read_lock_sym_bp =
+ if (!tracepoint_dlopen_ptr->rcu_read_lock_sym)
+ tracepoint_dlopen_ptr->rcu_read_lock_sym =
URCU_FORCE_CAST(void (*)(void),
dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
- "tp_rcu_read_lock_bp"));
- if (!tracepoint_dlopen_ptr->rcu_read_unlock_sym_bp)
- tracepoint_dlopen_ptr->rcu_read_unlock_sym_bp =
+ "tp_rcu_read_lock"));
+ if (!tracepoint_dlopen_ptr->rcu_read_unlock_sym)
+ tracepoint_dlopen_ptr->rcu_read_unlock_sym =
URCU_FORCE_CAST(void (*)(void),
dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
- "tp_rcu_read_unlock_bp"));
- if (!tracepoint_dlopen_ptr->rcu_dereference_sym_bp)
- tracepoint_dlopen_ptr->rcu_dereference_sym_bp =
+ "tp_rcu_read_unlock"));
+ if (!tracepoint_dlopen_ptr->rcu_dereference_sym)
+ tracepoint_dlopen_ptr->rcu_dereference_sym =
URCU_FORCE_CAST(void *(*)(void *p),
dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
- "tp_rcu_dereference_sym_bp"));
+ "tp_rcu_dereference_sym"));
}
#else
static inline void lttng_ust_notrace
}
#endif
-static void lttng_ust_notrace __attribute__((constructor))
-__tracepoints__init(void);
+static void
+__tracepoints__init(void)
+ lttng_ust_notrace __attribute__((constructor));
static void
__tracepoints__init(void)
{
tracepoint_dlopen_ptr = &tracepoint_dlopen;
if (!tracepoint_dlopen_ptr->liblttngust_handle)
tracepoint_dlopen_ptr->liblttngust_handle =
- dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
+ dlopen(LTTNG_UST_TRACEPOINT_LIB_SONAME, RTLD_NOW | RTLD_GLOBAL);
if (!tracepoint_dlopen_ptr->liblttngust_handle)
return;
__tracepoint__init_urcu_sym();
*/
return;
}
- /*
- * Lookup if destructors must be executed using the old method.
- */
- if (tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors
- && *tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors) {
- /*
- * The old_tracepoint_disable_destructors symbol was found with
- * dlsym but its value is 1 meaning that destructors must not
- * be executed.
- */
- return;
- }
-
ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle);
if (ret) {
fprintf(stderr, "Error (%d) in dlclose\n", ret);
__attribute__((section("__tracepoints_strings"))) = \
#_provider ":" #_name; \
struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name \
- __attribute__((section("__tracepoints"))) = \
- { \
+ __attribute__((section("__tracepoints"))) = { \
+ sizeof(struct lttng_ust_tracepoint), \
__tp_strtab_##_provider##___##_name, \
0, \
NULL, \
_TRACEPOINT_UNDEFINED_REF(_provider), \
_TP_EXTRACT_STRING(_args), \
- { }, \
}; \
static struct lttng_ust_tracepoint * \
__tracepoint_ptr_##_provider##___##_name \
__lttng_ust_variable_attribute_no_sanitize_address = \
&__tracepoint_##_provider##___##_name;
-static void lttng_ust_notrace __attribute__((constructor))
-__tracepoints__ptrs_init(void);
+static void
+__tracepoints__ptrs_init(void)
+ lttng_ust_notrace __attribute__((constructor));
static void
__tracepoints__ptrs_init(void)
{
tracepoint_dlopen_ptr = &tracepoint_dlopen;
if (!tracepoint_dlopen_ptr->liblttngust_handle)
tracepoint_dlopen_ptr->liblttngust_handle =
- dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
+ dlopen(LTTNG_UST_TRACEPOINT_LIB_SONAME, RTLD_NOW | RTLD_GLOBAL);
if (!tracepoint_dlopen_ptr->liblttngust_handle)
return;
if (!tracepoint_destructors_syms_ptr)
URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *),
dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tracepoint_unregister_lib"));
- tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors =
- URCU_FORCE_CAST(int *,
- dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
- "__tracepoints__disable_destructors"));
tracepoint_destructors_syms_ptr->tracepoint_disable_destructors =
URCU_FORCE_CAST(void (*)(void),
dlsym(tracepoint_dlopen_ptr->liblttngust_handle,