5 * Code markup for dynamic and static tracing.
7 * See Documentation/marker.txt.
9 * (C) Copyright 2006 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
10 * (C) Copyright 2009 Pierre-Marc Fournier <pierre-marc dot fournier at polymtl dot ca>
11 * (C) Copyright 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
13 * This library is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU Lesser General Public
15 * License as published by the Free Software Foundation;
16 * version 2.1 of the License.
18 * This library is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * Lesser General Public License for more details.
23 * You should have received a copy of the GNU Lesser General Public
24 * License along with this library; if not, write to the Free Software
25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 #include <bits/wordsize.h>
30 #include <urcu/list.h>
32 #include <ust/kcompat/kcompat.h>
37 * ust_marker_probe_func - Type of a marker probe function
39 * @probe_private: probe private data
40 * @call_private: call site private data
42 * @args: variable argument list pointer. Use a pointer to overcome C's
43 * inability to pass this around as a pointer in a portable manner in
44 * the callee otherwise.
46 * Type of marker probe functions. They receive the mdata and need to parse the
47 * format string to recover the variable argument list.
49 typedef void ust_marker_probe_func(const struct ust_marker
*mdata
,
50 void *probe_private
, void *call_private
,
51 const char *fmt
, va_list *args
);
53 struct ust_marker_probe_closure
{
54 ust_marker_probe_func
*func
; /* Callback */
55 void *probe_private
; /* Private probe data */
59 const char *channel
; /* Name of channel where to send data */
60 const char *name
; /* Marker name */
61 const char *format
; /* Marker format string, describing the
62 * variable argument list.
64 char state
; /* State. */
65 char ptype
; /* probe type : 0 : single, 1 : multi */
67 u16 channel_id
; /* Numeric channel identifier, dynamic */
68 u16 event_id
; /* Numeric event identifier, dynamic */
69 void (*call
)(const struct ust_marker
*mdata
, void *call_private
, ...);
70 struct ust_marker_probe_closure single
;
71 struct ust_marker_probe_closure
*multi
;
72 const char *tp_name
; /* Optional tracepoint name */
73 void *tp_cb
; /* Optional tracepoint callback */
77 * We keep the "channel" as internal field for marker.c *only*. It will be
82 * __ust_marker_ptrs section is not const (read-only) because it needs to be
83 * read-write to let the linker apply relocations and keep the object PIC.
85 #define _DEFINE_UST_MARKER(channel, name, tp_name_str, tp_cb, format) \
86 static const char __mstrtab_##channel##_##name[] \
87 __attribute__((section("__ust_markers_strings"))) \
88 = #channel "\0" #name "\0" format; \
89 static struct ust_marker __ust_marker_def_##name \
90 __attribute__((section("__ust_markers"))) = \
91 { __mstrtab_##channel##_##name, \
92 &__mstrtab_##channel##_##name[sizeof(#channel)], \
93 &__mstrtab_##channel##_##name[sizeof(#channel) + \
95 0, 0, 0, 0, ust_marker_probe_cb, \
96 { __ust_marker_empty_function, NULL}, \
97 NULL, tp_name_str, tp_cb }; \
98 static struct ust_marker * __ust_marker_ptr_##name \
99 __attribute__((used, section("__ust_marker_ptrs"))) = \
100 &__ust_marker_def_##name
103 * Make sure the alignment of the structure in the __ust_marker section will
104 * not add unwanted padding between the beginning of the section and the
105 * structure. Force alignment to the same alignment as the section start.
108 #define __ust_marker(channel, name, call_private, format, args...) \
110 _DEFINE_UST_MARKER(channel, name, NULL, NULL, format); \
111 __ust_marker_check_format(format, ## args); \
112 if (unlikely(__ust_marker_def_##name.state)) \
113 (__ust_marker_def_##name.call) \
114 (&__ust_marker_def_##name, call_private,\
119 * ust_marker - Marker using code patching
120 * @name: marker name, not quoted.
121 * @format: format string
122 * @args...: variable argument list
124 * Places a marker at caller site.
126 #define ust_marker(name, format, args...) \
127 __ust_marker(ust, name, NULL, format, ## args)
129 static inline __attribute__((deprecated
))
130 void __trace_mark_is_deprecated()
135 * UST_MARKER_NOARGS - Format string for a marker with no argument.
137 #define UST_MARKER_NOARGS " "
139 /* To be used for string format validity checking with gcc */
141 void __printf(1, 2) ___ust_marker_check_format(const char *fmt
, ...)
145 #define __ust_marker_check_format(format, args...) \
148 ___ust_marker_check_format(format, ## args); \
151 extern ust_marker_probe_func __ust_marker_empty_function
;
153 extern void ust_marker_probe_cb(const struct ust_marker
*mdata
,
154 void *call_private
, ...);
156 struct ust_marker_lib
{
157 struct ust_marker
* const *ust_marker_start
;
158 int ust_marker_count
;
159 struct cds_list_head list
;
162 #define UST_MARKER_LIB \
163 extern struct ust_marker * const __start___ust_marker_ptrs[] __attribute__((weak, visibility("hidden"))); \
164 extern struct ust_marker * const __stop___ust_marker_ptrs[] __attribute__((weak, visibility("hidden"))); \
165 static struct ust_marker * __ust_marker_ptr_dummy \
166 __attribute__((used, section("__ust_marker_ptrs"))); \
168 static void __attribute__((constructor)) __ust_marker__init(void) \
170 ust_marker_register_lib(__start___ust_marker_ptrs, \
171 __stop___ust_marker_ptrs \
172 - __start___ust_marker_ptrs); \
175 static void __attribute__((destructor)) __ust_marker__destroy(void) \
177 ust_marker_unregister_lib(__start___ust_marker_ptrs); \
181 int ust_marker_register_lib(struct ust_marker
* const *ust_marker_start
,
182 int ust_marker_count
);
184 int ust_marker_unregister_lib(struct ust_marker
* const *ust_marker_start
);
187 * trace_mark() -- DEPRECATED
188 * @channel: name prefix, not quoted. Ignored.
189 * @name: marker name, not quoted.
190 * @format: format string
191 * @args...: variable argument list
193 * Kept as a compatibility API and is *DEPRECATED* in favor of
196 #define trace_mark(channel, name, format, args...) \
197 __trace_mark_is_deprecated(); \
198 ust_marker(name, format, ## args)
200 static inline __attribute__((deprecated
))
201 void __MARKER_LIB_IS_DEPRECATED()
206 * MARKER_LIB is kept for backward compatibility and is *DEPRECATED*.
207 * Use UST_MARKER_LIB instead.
210 __MARKER_LIB_IS_DEPRECATED(); \
214 * MARKER_NOARGS - Compatibility API. *DEPRECATED*. Use
215 * UST_MARKER_NOARGS instead.
217 #define MARK_NOARGS UST_MARKER_NOARGS
219 #endif /* _UST_MARKER_H */