Root/
1 | #ifndef _LINUX_TRACEPOINT_H |
2 | #define _LINUX_TRACEPOINT_H |
3 | |
4 | /* |
5 | * Kernel Tracepoint API. |
6 | * |
7 | * See Documentation/trace/tracepoints.txt. |
8 | * |
9 | * (C) Copyright 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
10 | * |
11 | * Heavily inspired from the Linux Kernel Markers. |
12 | * |
13 | * This file is released under the GPLv2. |
14 | * See the file COPYING for more details. |
15 | */ |
16 | |
17 | #include <linux/errno.h> |
18 | #include <linux/types.h> |
19 | #include <linux/rcupdate.h> |
20 | #include <linux/static_key.h> |
21 | |
22 | struct module; |
23 | struct tracepoint; |
24 | |
25 | struct tracepoint_func { |
26 | void *func; |
27 | void *data; |
28 | }; |
29 | |
30 | struct tracepoint { |
31 | const char *name; /* Tracepoint name */ |
32 | struct static_key key; |
33 | void (*regfunc)(void); |
34 | void (*unregfunc)(void); |
35 | struct tracepoint_func __rcu *funcs; |
36 | }; |
37 | |
38 | /* |
39 | * Connect a probe to a tracepoint. |
40 | * Internal API, should not be used directly. |
41 | */ |
42 | extern int tracepoint_probe_register(const char *name, void *probe, void *data); |
43 | |
44 | /* |
45 | * Disconnect a probe from a tracepoint. |
46 | * Internal API, should not be used directly. |
47 | */ |
48 | extern int |
49 | tracepoint_probe_unregister(const char *name, void *probe, void *data); |
50 | |
51 | extern int tracepoint_probe_register_noupdate(const char *name, void *probe, |
52 | void *data); |
53 | extern int tracepoint_probe_unregister_noupdate(const char *name, void *probe, |
54 | void *data); |
55 | extern void tracepoint_probe_update_all(void); |
56 | |
57 | #ifdef CONFIG_MODULES |
58 | struct tp_module { |
59 | struct list_head list; |
60 | unsigned int num_tracepoints; |
61 | struct tracepoint * const *tracepoints_ptrs; |
62 | }; |
63 | #endif /* CONFIG_MODULES */ |
64 | |
65 | struct tracepoint_iter { |
66 | #ifdef CONFIG_MODULES |
67 | struct tp_module *module; |
68 | #endif /* CONFIG_MODULES */ |
69 | struct tracepoint * const *tracepoint; |
70 | }; |
71 | |
72 | extern void tracepoint_iter_start(struct tracepoint_iter *iter); |
73 | extern void tracepoint_iter_next(struct tracepoint_iter *iter); |
74 | extern void tracepoint_iter_stop(struct tracepoint_iter *iter); |
75 | extern void tracepoint_iter_reset(struct tracepoint_iter *iter); |
76 | |
77 | /* |
78 | * tracepoint_synchronize_unregister must be called between the last tracepoint |
79 | * probe unregistration and the end of module exit to make sure there is no |
80 | * caller executing a probe when it is freed. |
81 | */ |
82 | static inline void tracepoint_synchronize_unregister(void) |
83 | { |
84 | synchronize_sched(); |
85 | } |
86 | |
87 | #define PARAMS(args...) args |
88 | |
89 | #endif /* _LINUX_TRACEPOINT_H */ |
90 | |
91 | /* |
92 | * Note: we keep the TRACE_EVENT and DECLARE_TRACE outside the include |
93 | * file ifdef protection. |
94 | * This is due to the way trace events work. If a file includes two |
95 | * trace event headers under one "CREATE_TRACE_POINTS" the first include |
96 | * will override the TRACE_EVENT and break the second include. |
97 | */ |
98 | |
99 | #ifndef DECLARE_TRACE |
100 | |
101 | #define TP_PROTO(args...) args |
102 | #define TP_ARGS(args...) args |
103 | #define TP_CONDITION(args...) args |
104 | |
105 | #ifdef CONFIG_TRACEPOINTS |
106 | |
107 | /* |
108 | * it_func[0] is never NULL because there is at least one element in the array |
109 | * when the array itself is non NULL. |
110 | * |
111 | * Note, the proto and args passed in includes "__data" as the first parameter. |
112 | * The reason for this is to handle the "void" prototype. If a tracepoint |
113 | * has a "void" prototype, then it is invalid to declare a function |
114 | * as "(void *, void)". The DECLARE_TRACE_NOARGS() will pass in just |
115 | * "void *data", where as the DECLARE_TRACE() will pass in "void *data, proto". |
116 | */ |
117 | #define __DO_TRACE(tp, proto, args, cond, prercu, postrcu) \ |
118 | do { \ |
119 | struct tracepoint_func *it_func_ptr; \ |
120 | void *it_func; \ |
121 | void *__data; \ |
122 | \ |
123 | if (!(cond)) \ |
124 | return; \ |
125 | prercu; \ |
126 | rcu_read_lock_sched_notrace(); \ |
127 | it_func_ptr = rcu_dereference_sched((tp)->funcs); \ |
128 | if (it_func_ptr) { \ |
129 | do { \ |
130 | it_func = (it_func_ptr)->func; \ |
131 | __data = (it_func_ptr)->data; \ |
132 | ((void(*)(proto))(it_func))(args); \ |
133 | } while ((++it_func_ptr)->func); \ |
134 | } \ |
135 | rcu_read_unlock_sched_notrace(); \ |
136 | postrcu; \ |
137 | } while (0) |
138 | |
139 | #ifndef MODULE |
140 | #define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \ |
141 | static inline void trace_##name##_rcuidle(proto) \ |
142 | { \ |
143 | if (static_key_false(&__tracepoint_##name.key)) \ |
144 | __DO_TRACE(&__tracepoint_##name, \ |
145 | TP_PROTO(data_proto), \ |
146 | TP_ARGS(data_args), \ |
147 | TP_CONDITION(cond), \ |
148 | rcu_irq_enter(), \ |
149 | rcu_irq_exit()); \ |
150 | } |
151 | #else |
152 | #define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) |
153 | #endif |
154 | |
155 | /* |
156 | * Make sure the alignment of the structure in the __tracepoints section will |
157 | * not add unwanted padding between the beginning of the section and the |
158 | * structure. Force alignment to the same alignment as the section start. |
159 | */ |
160 | #define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ |
161 | extern struct tracepoint __tracepoint_##name; \ |
162 | static inline void trace_##name(proto) \ |
163 | { \ |
164 | if (static_key_false(&__tracepoint_##name.key)) \ |
165 | __DO_TRACE(&__tracepoint_##name, \ |
166 | TP_PROTO(data_proto), \ |
167 | TP_ARGS(data_args), \ |
168 | TP_CONDITION(cond),,); \ |
169 | } \ |
170 | __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ |
171 | PARAMS(cond), PARAMS(data_proto), PARAMS(data_args)) \ |
172 | static inline int \ |
173 | register_trace_##name(void (*probe)(data_proto), void *data) \ |
174 | { \ |
175 | return tracepoint_probe_register(#name, (void *)probe, \ |
176 | data); \ |
177 | } \ |
178 | static inline int \ |
179 | unregister_trace_##name(void (*probe)(data_proto), void *data) \ |
180 | { \ |
181 | return tracepoint_probe_unregister(#name, (void *)probe, \ |
182 | data); \ |
183 | } \ |
184 | static inline void \ |
185 | check_trace_callback_type_##name(void (*cb)(data_proto)) \ |
186 | { \ |
187 | } |
188 | |
189 | /* |
190 | * We have no guarantee that gcc and the linker won't up-align the tracepoint |
191 | * structures, so we create an array of pointers that will be used for iteration |
192 | * on the tracepoints. |
193 | */ |
194 | #define DEFINE_TRACE_FN(name, reg, unreg) \ |
195 | static const char __tpstrtab_##name[] \ |
196 | __attribute__((section("__tracepoints_strings"))) = #name; \ |
197 | struct tracepoint __tracepoint_##name \ |
198 | __attribute__((section("__tracepoints"))) = \ |
199 | { __tpstrtab_##name, STATIC_KEY_INIT_FALSE, reg, unreg, NULL };\ |
200 | static struct tracepoint * const __tracepoint_ptr_##name __used \ |
201 | __attribute__((section("__tracepoints_ptrs"))) = \ |
202 | &__tracepoint_##name; |
203 | |
204 | #define DEFINE_TRACE(name) \ |
205 | DEFINE_TRACE_FN(name, NULL, NULL); |
206 | |
207 | #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \ |
208 | EXPORT_SYMBOL_GPL(__tracepoint_##name) |
209 | #define EXPORT_TRACEPOINT_SYMBOL(name) \ |
210 | EXPORT_SYMBOL(__tracepoint_##name) |
211 | |
212 | #else /* !CONFIG_TRACEPOINTS */ |
213 | #define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ |
214 | static inline void trace_##name(proto) \ |
215 | { } \ |
216 | static inline void trace_##name##_rcuidle(proto) \ |
217 | { } \ |
218 | static inline int \ |
219 | register_trace_##name(void (*probe)(data_proto), \ |
220 | void *data) \ |
221 | { \ |
222 | return -ENOSYS; \ |
223 | } \ |
224 | static inline int \ |
225 | unregister_trace_##name(void (*probe)(data_proto), \ |
226 | void *data) \ |
227 | { \ |
228 | return -ENOSYS; \ |
229 | } \ |
230 | static inline void check_trace_callback_type_##name(void (*cb)(data_proto)) \ |
231 | { \ |
232 | } |
233 | |
234 | #define DEFINE_TRACE_FN(name, reg, unreg) |
235 | #define DEFINE_TRACE(name) |
236 | #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) |
237 | #define EXPORT_TRACEPOINT_SYMBOL(name) |
238 | |
239 | #endif /* CONFIG_TRACEPOINTS */ |
240 | |
241 | /* |
242 | * The need for the DECLARE_TRACE_NOARGS() is to handle the prototype |
243 | * (void). "void" is a special value in a function prototype and can |
244 | * not be combined with other arguments. Since the DECLARE_TRACE() |
245 | * macro adds a data element at the beginning of the prototype, |
246 | * we need a way to differentiate "(void *data, proto)" from |
247 | * "(void *data, void)". The second prototype is invalid. |
248 | * |
249 | * DECLARE_TRACE_NOARGS() passes "void" as the tracepoint prototype |
250 | * and "void *__data" as the callback prototype. |
251 | * |
252 | * DECLARE_TRACE() passes "proto" as the tracepoint protoype and |
253 | * "void *__data, proto" as the callback prototype. |
254 | */ |
255 | #define DECLARE_TRACE_NOARGS(name) \ |
256 | __DECLARE_TRACE(name, void, , 1, void *__data, __data) |
257 | |
258 | #define DECLARE_TRACE(name, proto, args) \ |
259 | __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \ |
260 | PARAMS(void *__data, proto), \ |
261 | PARAMS(__data, args)) |
262 | |
263 | #define DECLARE_TRACE_CONDITION(name, proto, args, cond) \ |
264 | __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), PARAMS(cond), \ |
265 | PARAMS(void *__data, proto), \ |
266 | PARAMS(__data, args)) |
267 | |
268 | #define TRACE_EVENT_FLAGS(event, flag) |
269 | |
270 | #define TRACE_EVENT_PERF_PERM(event, expr...) |
271 | |
272 | #endif /* DECLARE_TRACE */ |
273 | |
274 | #ifndef TRACE_EVENT |
275 | /* |
276 | * For use with the TRACE_EVENT macro: |
277 | * |
278 | * We define a tracepoint, its arguments, its printk format |
279 | * and its 'fast binay record' layout. |
280 | * |
281 | * Firstly, name your tracepoint via TRACE_EVENT(name : the |
282 | * 'subsystem_event' notation is fine. |
283 | * |
284 | * Think about this whole construct as the |
285 | * 'trace_sched_switch() function' from now on. |
286 | * |
287 | * |
288 | * TRACE_EVENT(sched_switch, |
289 | * |
290 | * * |
291 | * * A function has a regular function arguments |
292 | * * prototype, declare it via TP_PROTO(): |
293 | * * |
294 | * |
295 | * TP_PROTO(struct rq *rq, struct task_struct *prev, |
296 | * struct task_struct *next), |
297 | * |
298 | * * |
299 | * * Define the call signature of the 'function'. |
300 | * * (Design sidenote: we use this instead of a |
301 | * * TP_PROTO1/TP_PROTO2/TP_PROTO3 ugliness.) |
302 | * * |
303 | * |
304 | * TP_ARGS(rq, prev, next), |
305 | * |
306 | * * |
307 | * * Fast binary tracing: define the trace record via |
308 | * * TP_STRUCT__entry(). You can think about it like a |
309 | * * regular C structure local variable definition. |
310 | * * |
311 | * * This is how the trace record is structured and will |
312 | * * be saved into the ring buffer. These are the fields |
313 | * * that will be exposed to user-space in |
314 | * * /sys/kernel/debug/tracing/events/<*>/format. |
315 | * * |
316 | * * The declared 'local variable' is called '__entry' |
317 | * * |
318 | * * __field(pid_t, prev_prid) is equivalent to a standard declariton: |
319 | * * |
320 | * * pid_t prev_pid; |
321 | * * |
322 | * * __array(char, prev_comm, TASK_COMM_LEN) is equivalent to: |
323 | * * |
324 | * * char prev_comm[TASK_COMM_LEN]; |
325 | * * |
326 | * |
327 | * TP_STRUCT__entry( |
328 | * __array( char, prev_comm, TASK_COMM_LEN ) |
329 | * __field( pid_t, prev_pid ) |
330 | * __field( int, prev_prio ) |
331 | * __array( char, next_comm, TASK_COMM_LEN ) |
332 | * __field( pid_t, next_pid ) |
333 | * __field( int, next_prio ) |
334 | * ), |
335 | * |
336 | * * |
337 | * * Assign the entry into the trace record, by embedding |
338 | * * a full C statement block into TP_fast_assign(). You |
339 | * * can refer to the trace record as '__entry' - |
340 | * * otherwise you can put arbitrary C code in here. |
341 | * * |
342 | * * Note: this C code will execute every time a trace event |
343 | * * happens, on an active tracepoint. |
344 | * * |
345 | * |
346 | * TP_fast_assign( |
347 | * memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN); |
348 | * __entry->prev_pid = prev->pid; |
349 | * __entry->prev_prio = prev->prio; |
350 | * memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN); |
351 | * __entry->next_pid = next->pid; |
352 | * __entry->next_prio = next->prio; |
353 | * ), |
354 | * |
355 | * * |
356 | * * Formatted output of a trace record via TP_printk(). |
357 | * * This is how the tracepoint will appear under ftrace |
358 | * * plugins that make use of this tracepoint. |
359 | * * |
360 | * * (raw-binary tracing wont actually perform this step.) |
361 | * * |
362 | * |
363 | * TP_printk("task %s:%d [%d] ==> %s:%d [%d]", |
364 | * __entry->prev_comm, __entry->prev_pid, __entry->prev_prio, |
365 | * __entry->next_comm, __entry->next_pid, __entry->next_prio), |
366 | * |
367 | * ); |
368 | * |
369 | * This macro construct is thus used for the regular printk format |
370 | * tracing setup, it is used to construct a function pointer based |
371 | * tracepoint callback (this is used by programmatic plugins and |
372 | * can also by used by generic instrumentation like SystemTap), and |
373 | * it is also used to expose a structured trace record in |
374 | * /sys/kernel/debug/tracing/events/. |
375 | * |
376 | * A set of (un)registration functions can be passed to the variant |
377 | * TRACE_EVENT_FN to perform any (un)registration work. |
378 | */ |
379 | |
380 | #define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print) |
381 | #define DEFINE_EVENT(template, name, proto, args) \ |
382 | DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) |
383 | #define DEFINE_EVENT_FN(template, name, proto, args, reg, unreg)\ |
384 | DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) |
385 | #define DEFINE_EVENT_PRINT(template, name, proto, args, print) \ |
386 | DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) |
387 | #define DEFINE_EVENT_CONDITION(template, name, proto, \ |
388 | args, cond) \ |
389 | DECLARE_TRACE_CONDITION(name, PARAMS(proto), \ |
390 | PARAMS(args), PARAMS(cond)) |
391 | |
392 | #define TRACE_EVENT(name, proto, args, struct, assign, print) \ |
393 | DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) |
394 | #define TRACE_EVENT_FN(name, proto, args, struct, \ |
395 | assign, print, reg, unreg) \ |
396 | DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) |
397 | #define TRACE_EVENT_CONDITION(name, proto, args, cond, \ |
398 | struct, assign, print) \ |
399 | DECLARE_TRACE_CONDITION(name, PARAMS(proto), \ |
400 | PARAMS(args), PARAMS(cond)) |
401 | |
402 | #define TRACE_EVENT_FLAGS(event, flag) |
403 | |
404 | #define TRACE_EVENT_PERF_PERM(event, expr...) |
405 | |
406 | #endif /* ifdef TRACE_EVENT (see note above) */ |
407 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9