* SOFTWARE.
*/
+#include <stdio.h>
+#include <stdlib.h>
#include <lttng/tracepoint-types.h>
#include <lttng/tracepoint-rcu.h>
#include <urcu/compiler.h>
+#include <urcu/system.h>
#include <dlfcn.h> /* for dlopen */
#include <string.h> /* for memset */
-#include <assert.h>
#include <lttng/ust-config.h> /* for sdt */
#include <lttng/ust-compiler.h>
#ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
#define SDT_USE_VARIADIC
#include <sys/sdt.h>
+#define LTTNG_STAP_PROBEV STAP_PROBEV
#else
-#define STAP_PROBEV(...)
+#define LTTNG_STAP_PROBEV(...)
#endif
#ifdef __cplusplus
extern "C" {
#endif
+#define tracepoint_enabled(provider, name) \
+ caa_unlikely(CMM_LOAD_SHARED(__tracepoint_##provider##___##name.state))
+
+#define do_tracepoint(provider, name, ...) \
+ __tracepoint_cb_##provider##___##name(__VA_ARGS__)
+
#define tracepoint(provider, name, ...) \
do { \
- STAP_PROBEV(provider, name, ## __VA_ARGS__); \
- if (caa_unlikely(__tracepoint_##provider##___##name.state)) \
- __tracepoint_cb_##provider##___##name(__VA_ARGS__); \
+ LTTNG_STAP_PROBEV(provider, name, ## __VA_ARGS__); \
+ if (tracepoint_enabled(provider, name)) \
+ do_tracepoint(provider, name, __VA_ARGS__); \
} while (0)
#define TP_ARGS(...) __VA_ARGS__
#define _TP_ARGS_DATA_VAR(...) _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
#define _TP_PARAMS(...) __VA_ARGS__
+/*
+ * The tracepoint cb is marked always inline so we can distinguish
+ * between caller's ip addresses within the probe using the return
+ * address.
+ */
#define _DECLARE_TRACEPOINT(_provider, _name, ...) \
-extern struct tracepoint __tracepoint_##_provider##___##_name; \
-static inline lttng_ust_notrace \
+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 \
+static \
void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
{ \
- struct tracepoint_probe *__tp_probe; \
+ struct lttng_ust_tracepoint_probe *__tp_probe; \
\
if (caa_unlikely(!TP_RCU_LINK_TEST())) \
return; \
if (caa_unlikely(!__tp_probe)) \
goto end; \
do { \
- void (*__tp_cb)(void) = __tp_probe->func; \
+ void (*__tp_cb)(void) = __tp_probe->func; \
void *__tp_data = __tp_probe->data; \
\
URCU_FORCE_CAST(void (*)(_TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb) \
* tracepoint dynamic linkage handling (callbacks). Hidden visibility:
* shared across objects in a module/main executable.
*/
-struct tracepoint_dlopen {
+struct lttng_ust_tracepoint_dlopen {
void *liblttngust_handle;
- int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start,
+ int (*tracepoint_register_lib)(struct lttng_ust_tracepoint * const *tracepoints_start,
int tracepoints_count);
- int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start);
-#ifndef _LGPL_SOURCE
+ 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);
-#endif
};
-extern struct tracepoint_dlopen tracepoint_dlopen;
+extern struct lttng_ust_tracepoint_dlopen tracepoint_dlopen;
+extern struct lttng_ust_tracepoint_dlopen *tracepoint_dlopen_ptr;
+
+/*
+ * These weak symbols, the constructor, and destructor take care of
+ * registering only _one_ instance of the tracepoints per shared-ojbect
+ * (or for the whole main program).
+ */
+int __tracepoint_registered
+ __attribute__((weak, visibility("hidden")));
+int __tracepoint_ptrs_registered
+ __attribute__((weak, visibility("hidden")));
+struct lttng_ust_tracepoint_dlopen tracepoint_dlopen
+ __attribute__((weak, visibility("hidden")));
+/*
+ * 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
+ * 32-bit powerpc depending on the object size: symbols for objects of 8
+ * bytes or less have the same address throughout a module, whereas they
+ * have different addresses between compile units for objects larger
+ * than 8 bytes. Add this pointer indirection to ensure that the symbol
+ * scoping match that of the other weak hidden symbols found in this
+ * header.
+ */
+struct lttng_ust_tracepoint_dlopen *tracepoint_dlopen_ptr
+ __attribute__((weak, visibility("hidden")));
+
+#ifndef _LGPL_SOURCE
+static inline void lttng_ust_notrace
+__tracepoint__init_urcu_sym(void);
+static inline void
+__tracepoint__init_urcu_sym(void)
+{
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ /*
+ * 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 =
+ 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 =
+ 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 =
+ URCU_FORCE_CAST(void *(*)(void *p),
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
+ "tp_rcu_dereference_sym_bp"));
+}
+#else
+static inline void lttng_ust_notrace
+__tracepoint__init_urcu_sym(void);
+static inline void
+__tracepoint__init_urcu_sym(void)
+{
+}
+#endif
+
+static void lttng_ust_notrace __attribute__((constructor))
+__tracepoints__init(void);
+static void
+__tracepoints__init(void)
+{
+ if (__tracepoint_registered++) {
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
+ return;
+ __tracepoint__init_urcu_sym();
+ return;
+ }
+
+ if (!tracepoint_dlopen_ptr)
+ 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);
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
+ return;
+ __tracepoint__init_urcu_sym();
+}
+
+static void lttng_ust_notrace __attribute__((destructor))
+__tracepoints__destroy(void);
+static void
+__tracepoints__destroy(void)
+{
+ int ret;
+
+ if (--__tracepoint_registered)
+ return;
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ if (tracepoint_dlopen_ptr->liblttngust_handle && !__tracepoint_ptrs_registered) {
+ ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle);
+ if (ret) {
+ fprintf(stderr, "Error (%d) in dlclose\n", ret);
+ abort();
+ }
+ memset(tracepoint_dlopen_ptr, 0, sizeof(*tracepoint_dlopen_ptr));
+ }
+}
#ifdef TRACEPOINT_DEFINE
* registering only _one_ instance of the tracepoints per shared-ojbect
* (or for the whole main program).
*/
-extern struct tracepoint * const __start___tracepoints_ptrs[]
+extern struct lttng_ust_tracepoint * const __start___tracepoints_ptrs[]
__attribute__((weak, visibility("hidden")));
-extern struct tracepoint * const __stop___tracepoints_ptrs[]
+extern struct lttng_ust_tracepoint * const __stop___tracepoints_ptrs[]
__attribute__((weak, visibility("hidden")));
/*
static const char __tp_strtab_##_provider##___##_name[] \
__attribute__((section("__tracepoints_strings"))) = \
#_provider ":" #_name; \
- struct tracepoint __tracepoint_##_provider##___##_name \
+ struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name \
__attribute__((section("__tracepoints"))) = \
{ \
__tp_strtab_##_provider##___##_name, \
NULL, \
_TRACEPOINT_UNDEFINED_REF(_provider), \
_TP_EXTRACT_STRING(_args), \
+ { }, \
}; \
- static struct tracepoint * __tracepoint_ptr_##_provider##___##_name \
+ static struct lttng_ust_tracepoint * \
+ __tracepoint_ptr_##_provider##___##_name \
__attribute__((used, section("__tracepoints_ptrs"))) = \
&__tracepoint_##_provider##___##_name;
-static inline void __tracepoints__init_define(void)
-{
- tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs,
- __stop___tracepoints_ptrs -
- __start___tracepoints_ptrs);
-}
-
-static inline void __tracepoints__destroy_define(void)
-{
- if (tracepoint_dlopen.tracepoint_unregister_lib)
- tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs);
-}
-
-
-#else /* TRACEPOINT_DEFINE */
-
-#define _DEFINE_TRACEPOINT(_provider, _name, _args)
-
-static inline void __tracepoints__init_define(void)
-{
-}
-
-static inline void __tracepoints__destroy_define(void)
-{
-}
-
-#endif /* #else TRACEPOINT_DEFINE */
-
-#if defined(TRACEPOINT_DEFINE) || defined(TRACEPOINT_CREATE_PROBES)
-
-/*
- * These weak symbols, the constructor, and destructor take care of
- * registering only _one_ instance of the tracepoints per shared-ojbect
- * (or for the whole main program).
- */
-int __tracepoint_registered
- __attribute__((weak, visibility("hidden")));
-struct tracepoint_dlopen tracepoint_dlopen
- __attribute__((weak, visibility("hidden")));
-
static void lttng_ust_notrace __attribute__((constructor))
-__tracepoints__init(void);
+__tracepoints__ptrs_init(void);
static void
-__tracepoints__init(void)
+__tracepoints__ptrs_init(void)
{
- if (__tracepoint_registered++)
+ if (__tracepoint_ptrs_registered++)
return;
-
- tracepoint_dlopen.liblttngust_handle =
- dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
- if (!tracepoint_dlopen.liblttngust_handle)
+ if (!tracepoint_dlopen_ptr)
+ 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);
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
return;
- tracepoint_dlopen.tracepoint_register_lib =
- URCU_FORCE_CAST(int (*)(struct tracepoint * const *, int),
- dlsym(tracepoint_dlopen.liblttngust_handle,
+ tracepoint_dlopen_ptr->tracepoint_register_lib =
+ URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *, int),
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tracepoint_register_lib"));
- tracepoint_dlopen.tracepoint_unregister_lib =
- URCU_FORCE_CAST(int (*)(struct tracepoint * const *),
- dlsym(tracepoint_dlopen.liblttngust_handle,
+ tracepoint_dlopen_ptr->tracepoint_unregister_lib =
+ URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *),
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tracepoint_unregister_lib"));
-#ifndef _LGPL_SOURCE
- tracepoint_dlopen.rcu_read_lock_sym_bp =
- URCU_FORCE_CAST(void (*)(void),
- dlsym(tracepoint_dlopen.liblttngust_handle,
- "tp_rcu_read_lock_bp"));
- tracepoint_dlopen.rcu_read_unlock_sym_bp =
- URCU_FORCE_CAST(void (*)(void),
- dlsym(tracepoint_dlopen.liblttngust_handle,
- "tp_rcu_read_unlock_bp"));
- tracepoint_dlopen.rcu_dereference_sym_bp =
- URCU_FORCE_CAST(void *(*)(void *p),
- dlsym(tracepoint_dlopen.liblttngust_handle,
- "tp_rcu_dereference_sym_bp"));
-#endif
- __tracepoints__init_define();
+ __tracepoint__init_urcu_sym();
+ if (tracepoint_dlopen_ptr->tracepoint_register_lib) {
+ tracepoint_dlopen_ptr->tracepoint_register_lib(__start___tracepoints_ptrs,
+ __stop___tracepoints_ptrs -
+ __start___tracepoints_ptrs);
+ }
}
static void lttng_ust_notrace __attribute__((destructor))
-__tracepoints__destroy(void);
+__tracepoints__ptrs_destroy(void);
static void
-__tracepoints__destroy(void)
+__tracepoints__ptrs_destroy(void)
{
int ret;
- if (--__tracepoint_registered)
+ if (--__tracepoint_ptrs_registered)
return;
- __tracepoints__destroy_define();
- if (tracepoint_dlopen.liblttngust_handle) {
- ret = dlclose(tracepoint_dlopen.liblttngust_handle);
- assert(!ret);
- memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ if (tracepoint_dlopen_ptr->tracepoint_unregister_lib)
+ tracepoint_dlopen_ptr->tracepoint_unregister_lib(__start___tracepoints_ptrs);
+ if (tracepoint_dlopen_ptr->liblttngust_handle && !__tracepoint_registered) {
+ ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle);
+ if (ret) {
+ fprintf(stderr, "Error (%d) in dlclose\n", ret);
+ abort();
+ }
+ memset(tracepoint_dlopen_ptr, 0, sizeof(*tracepoint_dlopen_ptr));
}
}
-#endif
+#else /* TRACEPOINT_DEFINE */
+
+#define _DEFINE_TRACEPOINT(_provider, _name, _args)
+
+#endif /* #else TRACEPOINT_DEFINE */
#ifdef __cplusplus
}
* debug information with line-level scope (TRACEPOINT_EVENT default)
*
* TRACE_DEBUG 14
- * debug-level message (trace_printf default)
+ * debug-level message
*
* Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT
* should be declared prior to the the TRACEPOINT_LOGLEVEL for a given
projects / lttng-ust.git / blobdiff