* SOFTWARE.
*/
+#include <stdio.h>
+#include <stdlib.h>
#include <lttng/tracepoint-types.h>
#include <lttng/tracepoint-rcu.h>
#include <urcu/compiler.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>
{ \
struct tracepoint_probe *__tp_probe; \
\
- if (!TP_RCU_LINK_TEST()) \
+ if (caa_unlikely(!TP_RCU_LINK_TEST())) \
return; \
tp_rcu_read_lock_bp(); \
__tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \
extern struct tracepoint_dlopen tracepoint_dlopen;
+#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")));
+int __tracepoint_ptrs_registered
+ __attribute__((weak, visibility("hidden")));
+struct tracepoint_dlopen tracepoint_dlopen
+ __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)
+{
+ /*
+ * Symbols below are needed by tracepoint call sites and probe
+ * providers.
+ */
+ if (!tracepoint_dlopen.rcu_read_lock_sym_bp)
+ tracepoint_dlopen.rcu_read_lock_sym_bp =
+ URCU_FORCE_CAST(void (*)(void),
+ dlsym(tracepoint_dlopen.liblttngust_handle,
+ "tp_rcu_read_lock_bp"));
+ if (!tracepoint_dlopen.rcu_read_unlock_sym_bp)
+ tracepoint_dlopen.rcu_read_unlock_sym_bp =
+ URCU_FORCE_CAST(void (*)(void),
+ dlsym(tracepoint_dlopen.liblttngust_handle,
+ "tp_rcu_read_unlock_bp"));
+ if (!tracepoint_dlopen.rcu_dereference_sym_bp)
+ tracepoint_dlopen.rcu_dereference_sym_bp =
+ URCU_FORCE_CAST(void *(*)(void *p),
+ dlsym(tracepoint_dlopen.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++)
+ return;
+
+ if (!tracepoint_dlopen.liblttngust_handle)
+ tracepoint_dlopen.liblttngust_handle =
+ dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
+ if (!tracepoint_dlopen.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.liblttngust_handle && !__tracepoint_ptrs_registered) {
+ ret = dlclose(tracepoint_dlopen.liblttngust_handle);
+ if (ret) {
+ fprintf(stderr, "Error (%d) in dlclose\n", ret);
+ abort();
+ }
+ memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
+ }
+}
+
+#endif
+
#ifdef TRACEPOINT_DEFINE
+/*
+ * 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).
+ */
+extern struct tracepoint * const __start___tracepoints_ptrs[]
+ __attribute__((weak, visibility("hidden")));
+extern struct tracepoint * const __stop___tracepoints_ptrs[]
+ __attribute__((weak, visibility("hidden")));
+
/*
* When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
* unresolved symbol that requires the provider to be linked in. When
NULL, \
_TRACEPOINT_UNDEFINED_REF(_provider), \
_TP_EXTRACT_STRING(_args), \
+ { }, \
}; \
static struct tracepoint * __tracepoint_ptr_##_provider##___##_name \
__attribute__((used, section("__tracepoints_ptrs"))) = \
&__tracepoint_##_provider##___##_name;
-/*
- * 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).
- */
-extern struct tracepoint * const __start___tracepoints_ptrs[]
- __attribute__((weak, visibility("hidden")));
-extern struct tracepoint * const __stop___tracepoints_ptrs[]
- __attribute__((weak, visibility("hidden")));
-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)
+ tracepoint_dlopen.liblttngust_handle =
+ dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
if (!tracepoint_dlopen.liblttngust_handle)
return;
tracepoint_dlopen.tracepoint_register_lib =
URCU_FORCE_CAST(int (*)(struct tracepoint * const *),
dlsym(tracepoint_dlopen.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
- tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs,
+ __tracepoint__init_urcu_sym();
+ if (tracepoint_dlopen.tracepoint_register_lib) {
+ tracepoint_dlopen.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;
if (tracepoint_dlopen.tracepoint_unregister_lib)
tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs);
- if (tracepoint_dlopen.liblttngust_handle) {
+ if (tracepoint_dlopen.liblttngust_handle && !__tracepoint_registered) {
ret = dlclose(tracepoint_dlopen.liblttngust_handle);
- assert(!ret);
+ if (ret) {
+ fprintf(stderr, "Error (%d) in dlclose\n", ret);
+ abort();
+ }
memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
}
}
projects / lttng-ust.git / blobdiff