#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 <lttng/ust-config.h> /* for sdt */
#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
#endif
#define tracepoint_enabled(provider, name) \
- caa_unlikely(__tracepoint_##provider##___##name.state)
+ 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__); \
+ LTTNG_STAP_PROBEV(provider, name, ## __VA_ARGS__); \
if (tracepoint_enabled(provider, name)) \
do_tracepoint(provider, name, __VA_ARGS__); \
} while (0)
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);
-#ifndef _LGPL_SOURCE
void (*rcu_read_lock_sym_bp)(void);
void (*rcu_read_unlock_sym_bp)(void);
void *(*rcu_dereference_sym_bp)(void *p);
-#endif
};
extern struct lttng_ust_tracepoint_dlopen tracepoint_dlopen;
-
-#if defined(TRACEPOINT_DEFINE) || defined(TRACEPOINT_CREATE_PROBES)
+extern struct lttng_ust_tracepoint_dlopen *tracepoint_dlopen_ptr;
/*
* These weak symbols, the constructor, and destructor take care of
__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")));
+
+/*
+ * 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.
+ */
+struct lttng_ust_tracepoint_destructors_syms {
+ int *old_tracepoint_disable_destructors;
+ void (*tracepoint_disable_destructors)(void);
+ int (*tracepoint_get_destructors_state)(void);
+};
+
+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")));
+struct lttng_ust_tracepoint_destructors_syms *tracepoint_destructors_syms_ptr
+ __attribute__((weak, visibility("hidden")));
+
+static inline void tracepoint_disable_destructors(void)
+{
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ if (!tracepoint_destructors_syms_ptr)
+ tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms;
+ 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
static inline void lttng_ust_notrace
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.rcu_read_lock_sym_bp)
- tracepoint_dlopen.rcu_read_lock_sym_bp =
+ 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.liblttngust_handle,
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tp_rcu_read_lock_bp"));
- if (!tracepoint_dlopen.rcu_read_unlock_sym_bp)
- tracepoint_dlopen.rcu_read_unlock_sym_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.liblttngust_handle,
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tp_rcu_read_unlock_bp"));
- if (!tracepoint_dlopen.rcu_dereference_sym_bp)
- tracepoint_dlopen.rcu_dereference_sym_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.liblttngust_handle,
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tp_rcu_dereference_sym_bp"));
}
#else
static void
__tracepoints__init(void)
{
- if (__tracepoint_registered++)
+ if (__tracepoint_registered++) {
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
+ return;
+ __tracepoint__init_urcu_sym();
return;
+ }
- if (!tracepoint_dlopen.liblttngust_handle)
- 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.liblttngust_handle)
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
return;
__tracepoint__init_urcu_sym();
}
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));
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ if (!tracepoint_destructors_syms_ptr)
+ tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms;
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
+ return;
+ if (__tracepoint_ptrs_registered)
+ return;
+ /*
+ * Lookup if destructors must be executed using the new method.
+ */
+ if (tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state
+ && !tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state()) {
+ /*
+ * The tracepoint_get_destructors_state symbol was found with
+ * dlsym but its returned value is 0 meaning that destructors
+ * must not be executed.
+ */
+ 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;
}
-}
-#endif
+ 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
{
if (__tracepoint_ptrs_registered++)
return;
- if (!tracepoint_dlopen.liblttngust_handle)
- 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.liblttngust_handle)
+ if (!tracepoint_dlopen_ptr->liblttngust_handle)
return;
- tracepoint_dlopen.tracepoint_register_lib =
+ if (!tracepoint_destructors_syms_ptr)
+ tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms;
+ tracepoint_dlopen_ptr->tracepoint_register_lib =
URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *, int),
- dlsym(tracepoint_dlopen.liblttngust_handle,
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
"tracepoint_register_lib"));
- tracepoint_dlopen.tracepoint_unregister_lib =
+ tracepoint_dlopen_ptr->tracepoint_unregister_lib =
URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *),
- dlsym(tracepoint_dlopen.liblttngust_handle,
+ 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,
+ "tp_disable_destructors"));
+ tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state =
+ URCU_FORCE_CAST(int (*)(void),
+ dlsym(tracepoint_dlopen_ptr->liblttngust_handle,
+ "tp_get_destructors_state"));
__tracepoint__init_urcu_sym();
- if (tracepoint_dlopen.tracepoint_register_lib) {
- tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs,
+ if (tracepoint_dlopen_ptr->tracepoint_register_lib) {
+ tracepoint_dlopen_ptr->tracepoint_register_lib(__start___tracepoints_ptrs,
__stop___tracepoints_ptrs -
__start___tracepoints_ptrs);
}
if (--__tracepoint_ptrs_registered)
return;
- if (tracepoint_dlopen.tracepoint_unregister_lib)
- tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs);
- if (tracepoint_dlopen.liblttngust_handle && !__tracepoint_registered) {
- ret = dlclose(tracepoint_dlopen.liblttngust_handle);
+ if (!tracepoint_dlopen_ptr)
+ tracepoint_dlopen_ptr = &tracepoint_dlopen;
+ if (!tracepoint_destructors_syms_ptr)
+ tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms;
+ if (tracepoint_dlopen_ptr->tracepoint_unregister_lib)
+ tracepoint_dlopen_ptr->tracepoint_unregister_lib(__start___tracepoints_ptrs);
+ if (tracepoint_dlopen_ptr->liblttngust_handle
+ && tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state
+ && tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state()
+ && !__tracepoint_ptrs_registered) {
+ ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle);
if (ret) {
fprintf(stderr, "Error (%d) in dlclose\n", ret);
abort();
}
- memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
+ memset(tracepoint_dlopen_ptr, 0, sizeof(*tracepoint_dlopen_ptr));
}
}
/* The following declarations must be outside re-inclusion protection. */
+#ifndef TRACEPOINT_ENUM
+
+/*
+ * Tracepoint Enumerations
+ *
+ * The enumeration is a mapping between an integer, or range of integers, and
+ * a string. It can be used to have a more compact trace in cases where the
+ * possible values for a field are limited:
+ *
+ * An example:
+ *
+ * TRACEPOINT_ENUM(someproject_component, enumname,
+ * TP_ENUM_VALUES(
+ * ctf_enum_value("even", 0)
+ * ctf_enum_value("uneven", 1)
+ * ctf_enum_range("twoto4", 2, 4)
+ * ctf_enum_value("five", 5)
+ * )
+ * )
+ *
+ * Where "someproject_component" is the name of the component this enumeration
+ * belongs to and "enumname" identifies this enumeration. Inside the
+ * TP_ENUM_VALUES macro is the actual mapping. Each string value can map
+ * to either a single value with ctf_enum_value or a range of values
+ * with ctf_enum_range.
+ *
+ * Enumeration ranges may overlap, but the behavior is implementation-defined,
+ * each trace reader will handle overlapping as it wishes.
+ *
+ * That enumeration can then be used in a field inside the TP_FIELD macro using
+ * the following line:
+ *
+ * ctf_enum(someproject_component, enumname, enumtype, enumfield, enumval)
+ *
+ * Where "someproject_component" and "enumname" match those in the
+ * TRACEPOINT_ENUM, "enumtype" is a signed or unsigned integer type
+ * backing the enumeration, "enumfield" is the name of the field and
+ * "enumval" is the value.
+ */
+
+#define TRACEPOINT_ENUM(provider, name, values)
+
+#endif /* #ifndef TRACEPOINT_ENUM */
+
#ifndef TRACEPOINT_EVENT
/*
* * Integer, printed with 0x base 16 *
* ctf_integer_hex(unsigned long, field_d, arg1)
*
+ * * Enumeration *
+ * ctf_enum(someproject_component, enum_name, int, field_e, arg0)
+ *
* * Array Sequence, printed as UTF8-encoded array of bytes *
* ctf_array_text(char, field_b, string, FIXED_LEN)
* ctf_sequence_text(char, field_c, string, size_t, strlen)
projects / lttng-ust.git / blobdiff