Fix a typo in a comment
[ghc.git] / rts / Trace.h
1 /* -----------------------------------------------------------------------------
2 *
3 * (c) The GHC Team, 2008-2009
4 *
5 * Support for fast binary event logging and user-space dtrace probes.
6 *
7 * ---------------------------------------------------------------------------*/
8
9 #ifndef TRACE_H
10 #define TRACE_H
11
12 #include "rts/EventLogFormat.h"
13 #include "Capability.h"
14
15 #if defined(DTRACE)
16 #include "RtsProbes.h"
17 #endif /* defined(DTRACE) */
18
19 #include "BeginPrivate.h"
20
21 // -----------------------------------------------------------------------------
22 // EventLog API
23 // -----------------------------------------------------------------------------
24
25 #if defined(TRACING)
26
27 void initTracing (void);
28 void endTracing (void);
29 void freeTracing (void);
30 void resetTracing (void);
31
32 #endif /* TRACING */
33
34 typedef StgWord32 CapsetID;
35 typedef StgWord16 CapsetType;
36 enum CapsetType { CapsetTypeCustom = CAPSET_TYPE_CUSTOM,
37 CapsetTypeOsProcess = CAPSET_TYPE_OSPROCESS,
38 CapsetTypeClockdomain = CAPSET_TYPE_CLOCKDOMAIN };
39 #define CAPSET_OSPROCESS_DEFAULT 0
40
41 // -----------------------------------------------------------------------------
42 // Message classes
43 // -----------------------------------------------------------------------------
44
45 // debugging flags, set with +RTS -D<something>
46 extern int DEBUG_sched;
47 extern int DEBUG_interp;
48 extern int DEBUG_weak;
49 extern int DEBUG_gccafs;
50 extern int DEBUG_gc;
51 extern int DEBUG_block_alloc;
52 extern int DEBUG_sanity;
53 extern int DEBUG_stable;
54 extern int DEBUG_stm;
55 extern int DEBUG_prof;
56 extern int DEBUG_gran;
57 extern int DEBUG_par;
58 extern int DEBUG_linker;
59 extern int DEBUG_squeeze;
60 extern int DEBUG_hpc;
61 extern int DEBUG_sparks;
62
63 // events
64 extern int TRACE_sched;
65
66 // -----------------------------------------------------------------------------
67 // Posting events
68 //
69 // We use macros rather than inline functions deliberately. We want
70 // the not-taken case to be as efficient as possible, a simple
71 // test-and-jump, and with inline functions gcc seemed to move some of
72 // the instructions from the branch up before the test.
73 //
74 // -----------------------------------------------------------------------------
75
76 #ifdef DEBUG
77 void traceBegin (const char *str, ...);
78 void traceEnd (void);
79 #endif
80
81 #ifdef TRACING
82
83 /*
84 * Record a scheduler event
85 */
86 #define traceSchedEvent(cap, tag, tso, other) \
87 if (RTS_UNLIKELY(TRACE_sched)) { \
88 traceSchedEvent_(cap, tag, tso, other, 0); \
89 }
90
91 #define traceSchedEvent2(cap, tag, tso, info1, info2) \
92 if (RTS_UNLIKELY(TRACE_sched)) { \
93 traceSchedEvent_(cap, tag, tso, info1, info2); \
94 }
95
96 void traceSchedEvent_ (Capability *cap, EventTypeNum tag,
97 StgTSO *tso, StgWord info1, StgWord info2);
98
99
100 /*
101 * Record a nullary event
102 */
103 #define traceEvent(cap, tag) \
104 if (RTS_UNLIKELY(TRACE_sched)) { \
105 traceEvent_(cap, tag); \
106 }
107
108 void traceEvent_ (Capability *cap, EventTypeNum tag);
109
110 // variadic macros are C99, and supported by gcc. However, the
111 // ##__VA_ARGS syntax is a gcc extension, which allows the variable
112 // argument list to be empty (see gcc docs for details).
113
114 /*
115 * Emit a trace message on a particular Capability
116 */
117 #define traceCap(class, cap, msg, ...) \
118 if (RTS_UNLIKELY(class)) { \
119 traceCap_(cap, msg, ##__VA_ARGS__); \
120 }
121
122 void traceCap_(Capability *cap, char *msg, ...);
123
124 /*
125 * Emit a trace message
126 */
127 #define trace(class, msg, ...) \
128 if (RTS_UNLIKELY(class)) { \
129 trace_(msg, ##__VA_ARGS__); \
130 }
131
132 void trace_(char *msg, ...);
133
134 /*
135 * A message or event emitted by the program
136 */
137 void traceUserMsg(Capability *cap, char *msg);
138
139 /*
140 * Emit a debug message (only when DEBUG is defined)
141 */
142 #ifdef DEBUG
143 #define debugTrace(class, msg, ...) \
144 if (RTS_UNLIKELY(class)) { \
145 trace_(msg, ##__VA_ARGS__); \
146 }
147 #else
148 #define debugTrace(class, str, ...) /* nothing */
149 #endif
150
151 #ifdef DEBUG
152 #define debugTraceCap(class, cap, msg, ...) \
153 if (RTS_UNLIKELY(class)) { \
154 traceCap_(cap, msg, ##__VA_ARGS__); \
155 }
156 #else
157 #define debugTraceCap(class, cap, str, ...) /* nothing */
158 #endif
159
160 /*
161 * Emit a message/event describing the state of a thread
162 */
163 #define traceThreadStatus(class, tso) \
164 if (RTS_UNLIKELY(class)) { \
165 traceThreadStatus_(tso); \
166 }
167
168 void traceThreadStatus_ (StgTSO *tso);
169
170 void traceEventStartup_ (int n_caps);
171
172 /*
173 * Events for describing capability sets in the eventlog
174 *
175 * Note: unlike other events, these are not conditional on TRACE_sched or
176 * similar because they are not "real" events themselves but provide
177 * information and context for other "real" events. Other events depend on
178 * the capset info events so for simplicity, rather than working out if
179 * they're necessary we always emit them. They should be very low volume.
180 */
181 void traceCapsetModify_ (EventTypeNum tag,
182 CapsetID capset,
183 StgWord32 other);
184
185 void traceOSProcessInfo_ (void);
186
187 #else /* !TRACING */
188
189 #define traceSchedEvent(cap, tag, tso, other) /* nothing */
190 #define traceSchedEvent2(cap, tag, tso, other, info) /* nothing */
191 #define traceEvent(cap, tag) /* nothing */
192 #define traceCap(class, cap, msg, ...) /* nothing */
193 #define trace(class, msg, ...) /* nothing */
194 #define debugTrace(class, str, ...) /* nothing */
195 #define debugTraceCap(class, cap, str, ...) /* nothing */
196 #define traceThreadStatus(class, tso) /* nothing */
197 #define traceEventStartup_(n_caps) /* nothing */
198 #define traceCapsetModify_(tag, capset, other) /* nothing */
199 #define traceOSProcessInfo_() /* nothing */
200
201 #endif /* TRACING */
202
203 // If DTRACE is enabled, but neither DEBUG nor TRACING, we need a C land
204 // wrapper for the user-msg probe (as we can't expand that in PrimOps.cmm)
205 //
206 #if !defined(DEBUG) && !defined(TRACING) && defined(DTRACE)
207
208 void dtraceUserMsgWrapper(Capability *cap, char *msg);
209
210 #endif /* !defined(DEBUG) && !defined(TRACING) && defined(DTRACE) */
211
212 // -----------------------------------------------------------------------------
213 // Aliases for static dtrace probes if dtrace is available
214 // -----------------------------------------------------------------------------
215
216 #if defined(DTRACE)
217
218 #define dtraceCreateThread(cap, tid) \
219 HASKELLEVENT_CREATE_THREAD(cap, tid)
220 #define dtraceRunThread(cap, tid) \
221 HASKELLEVENT_RUN_THREAD(cap, tid)
222 #define dtraceStopThread(cap, tid, status, info) \
223 HASKELLEVENT_STOP_THREAD(cap, tid, status, info)
224 #define dtraceThreadRunnable(cap, tid) \
225 HASKELLEVENT_THREAD_RUNNABLE(cap, tid)
226 #define dtraceMigrateThread(cap, tid, new_cap) \
227 HASKELLEVENT_MIGRATE_THREAD(cap, tid, new_cap)
228 #define dtraceRunSpark(cap, tid) \
229 HASKELLEVENT_RUN_SPARK(cap, tid)
230 #define dtraceStealSpark(cap, tid, victim_cap) \
231 HASKELLEVENT_STEAL_SPARK(cap, tid, victim_cap)
232 #define dtraceShutdown(cap) \
233 HASKELLEVENT_SHUTDOWN(cap)
234 #define dtraceThreadWakeup(cap, tid, other_cap) \
235 HASKELLEVENT_THREAD_WAKEUP(cap, tid, other_cap)
236 #define dtraceGcStart(cap) \
237 HASKELLEVENT_GC_START(cap)
238 #define dtraceGcEnd(cap) \
239 HASKELLEVENT_GC_END(cap)
240 #define dtraceRequestSeqGc(cap) \
241 HASKELLEVENT_REQUEST_SEQ_GC(cap)
242 #define dtraceRequestParGc(cap) \
243 HASKELLEVENT_REQUEST_PAR_GC(cap)
244 #define dtraceCreateSparkThread(cap, spark_tid) \
245 HASKELLEVENT_CREATE_SPARK_THREAD(cap, spark_tid)
246 #define dtraceStartup(num_caps) \
247 HASKELLEVENT_STARTUP(num_caps)
248 #define dtraceUserMsg(cap, msg) \
249 HASKELLEVENT_USER_MSG(cap, msg)
250 #define dtraceGcIdle(cap) \
251 HASKELLEVENT_GC_IDLE(cap)
252 #define dtraceGcWork(cap) \
253 HASKELLEVENT_GC_WORK(cap)
254 #define dtraceGcDone(cap) \
255 HASKELLEVENT_GC_DONE(cap)
256 #define dtraceCapsetCreate(capset, capset_type) \
257 HASKELLEVENT_CAPSET_CREATE(capset, capset_type)
258 #define dtraceCapsetDelete(capset) \
259 HASKELLEVENT_CAPSET_DELETE(capset)
260 #define dtraceCapsetAssignCap(capset, capno) \
261 HASKELLEVENT_CAPSET_ASSIGN_CAP(capset, capno)
262 #define dtraceCapsetRemoveCap(capset, capno) \
263 HASKELLEVENT_CAPSET_REMOVE_CAP(capset, capno)
264
265 #else /* !defined(DTRACE) */
266
267 #define dtraceCreateThread(cap, tid) /* nothing */
268 #define dtraceRunThread(cap, tid) /* nothing */
269 #define dtraceStopThread(cap, tid, status, info) /* nothing */
270 #define dtraceThreadRunnable(cap, tid) /* nothing */
271 #define dtraceMigrateThread(cap, tid, new_cap) /* nothing */
272 #define dtraceRunSpark(cap, tid) /* nothing */
273 #define dtraceStealSpark(cap, tid, victim_cap) /* nothing */
274 #define dtraceShutdown(cap) /* nothing */
275 #define dtraceThreadWakeup(cap, tid, other_cap) /* nothing */
276 #define dtraceGcStart(cap) /* nothing */
277 #define dtraceGcEnd(cap) /* nothing */
278 #define dtraceRequestSeqGc(cap) /* nothing */
279 #define dtraceRequestParGc(cap) /* nothing */
280 #define dtraceCreateSparkThread(cap, spark_tid) /* nothing */
281 #define dtraceStartup(num_caps) /* nothing */
282 #define dtraceUserMsg(cap, msg) /* nothing */
283 #define dtraceGcIdle(cap) /* nothing */
284 #define dtraceGcWork(cap) /* nothing */
285 #define dtraceGcDone(cap) /* nothing */
286 #define dtraceCapsetCreate(capset, capset_type) /* nothing */
287 #define dtraceCapsetDelete(capset) /* nothing */
288 #define dtraceCapsetAssignCap(capset, capno) /* nothing */
289 #define dtraceCapsetRemoveCap(capset, capno) /* nothing */
290
291 #endif
292
293 // -----------------------------------------------------------------------------
294 // Trace probes dispatching to various tracing frameworks
295 //
296 // In order to avoid accumulating multiple calls to tracing calls at trace
297 // points, we define inline probe functions that contain the various
298 // invocations.
299 //
300 // Dtrace - dtrace probes are unconditionally added as probe activation is
301 // handled by the dtrace component of the kernel, and inactive probes are
302 // very cheap — usually, one no-op. Consequently, dtrace can be used with
303 // all flavours of the RTS. In addition, we still support logging events to
304 // a file, even in the presence of dtrace. This is, eg, useful when tracing
305 // on a server, but browsing trace information with ThreadScope on a local
306 // client.
307 //
308 // -----------------------------------------------------------------------------
309
310 INLINE_HEADER void traceEventCreateThread(Capability *cap STG_UNUSED,
311 StgTSO *tso STG_UNUSED)
312 {
313 traceSchedEvent(cap, EVENT_CREATE_THREAD, tso, tso->stackobj->stack_size);
314 dtraceCreateThread((EventCapNo)cap->no, (EventThreadID)tso->id);
315 }
316
317 INLINE_HEADER void traceEventRunThread(Capability *cap STG_UNUSED,
318 StgTSO *tso STG_UNUSED)
319 {
320 traceSchedEvent(cap, EVENT_RUN_THREAD, tso, tso->what_next);
321 dtraceRunThread((EventCapNo)cap->no, (EventThreadID)tso->id);
322 }
323
324 INLINE_HEADER void traceEventStopThread(Capability *cap STG_UNUSED,
325 StgTSO *tso STG_UNUSED,
326 StgThreadReturnCode status STG_UNUSED,
327 StgWord32 info STG_UNUSED)
328 {
329 traceSchedEvent2(cap, EVENT_STOP_THREAD, tso, status, info);
330 dtraceStopThread((EventCapNo)cap->no, (EventThreadID)tso->id,
331 (EventThreadStatus)status, (EventThreadID)info);
332 }
333
334 // needs to be EXTERN_INLINE as it is used in another EXTERN_INLINE function
335 EXTERN_INLINE void traceEventThreadRunnable(Capability *cap STG_UNUSED,
336 StgTSO *tso STG_UNUSED);
337
338 EXTERN_INLINE void traceEventThreadRunnable(Capability *cap STG_UNUSED,
339 StgTSO *tso STG_UNUSED)
340 {
341 traceSchedEvent(cap, EVENT_THREAD_RUNNABLE, tso, 0);
342 dtraceThreadRunnable((EventCapNo)cap->no, (EventThreadID)tso->id);
343 }
344
345 INLINE_HEADER void traceEventMigrateThread(Capability *cap STG_UNUSED,
346 StgTSO *tso STG_UNUSED,
347 nat new_cap STG_UNUSED)
348 {
349 traceSchedEvent(cap, EVENT_MIGRATE_THREAD, tso, new_cap);
350 dtraceMigrateThread((EventCapNo)cap->no, (EventThreadID)tso->id,
351 (EventCapNo)new_cap);
352 }
353
354 INLINE_HEADER void traceEventRunSpark(Capability *cap STG_UNUSED,
355 StgTSO *tso STG_UNUSED)
356 {
357 traceSchedEvent(cap, EVENT_RUN_SPARK, tso, 0);
358 dtraceRunSpark((EventCapNo)cap->no, (EventThreadID)tso->id);
359 }
360
361 INLINE_HEADER void traceEventStealSpark(Capability *cap STG_UNUSED,
362 StgTSO *tso STG_UNUSED,
363 nat victim_cap STG_UNUSED)
364 {
365 traceSchedEvent(cap, EVENT_STEAL_SPARK, tso, victim_cap);
366 dtraceStealSpark((EventCapNo)cap->no, (EventThreadID)tso->id,
367 (EventCapNo)victim_cap);
368 }
369
370 INLINE_HEADER void traceEventShutdown(Capability *cap STG_UNUSED)
371 {
372 traceSchedEvent(cap, EVENT_SHUTDOWN, 0, 0);
373 dtraceShutdown((EventCapNo)cap->no);
374 }
375
376 INLINE_HEADER void traceEventThreadWakeup(Capability *cap STG_UNUSED,
377 StgTSO *tso STG_UNUSED,
378 nat other_cap STG_UNUSED)
379 {
380 traceSchedEvent(cap, EVENT_THREAD_WAKEUP, tso, other_cap);
381 dtraceThreadWakeup((EventCapNo)cap->no, (EventThreadID)tso->id,
382 (EventCapNo)other_cap);
383 }
384
385 INLINE_HEADER void traceEventGcStart(Capability *cap STG_UNUSED)
386 {
387 traceSchedEvent(cap, EVENT_GC_START, 0, 0);
388 dtraceGcStart((EventCapNo)cap->no);
389 }
390
391 INLINE_HEADER void traceEventGcEnd(Capability *cap STG_UNUSED)
392 {
393 traceSchedEvent(cap, EVENT_GC_END, 0, 0);
394 dtraceGcEnd((EventCapNo)cap->no);
395 }
396
397 INLINE_HEADER void traceEventRequestSeqGc(Capability *cap STG_UNUSED)
398 {
399 traceSchedEvent(cap, EVENT_REQUEST_SEQ_GC, 0, 0);
400 dtraceRequestSeqGc((EventCapNo)cap->no);
401 }
402
403 INLINE_HEADER void traceEventRequestParGc(Capability *cap STG_UNUSED)
404 {
405 traceSchedEvent(cap, EVENT_REQUEST_PAR_GC, 0, 0);
406 dtraceRequestParGc((EventCapNo)cap->no);
407 }
408
409 INLINE_HEADER void traceEventCreateSparkThread(Capability *cap STG_UNUSED,
410 StgThreadID spark_tid STG_UNUSED)
411 {
412 traceSchedEvent(cap, EVENT_CREATE_SPARK_THREAD, 0, spark_tid);
413 dtraceCreateSparkThread((EventCapNo)cap->no, (EventThreadID)spark_tid);
414 }
415
416 INLINE_HEADER void traceEventStartup(void)
417 {
418 int n_caps;
419 #ifdef THREADED_RTS
420 // XXX n_capabilities hasn't been initialised yet
421 n_caps = RtsFlags.ParFlags.nNodes;
422 #else
423 n_caps = 1;
424 #endif
425
426 traceEventStartup_(n_caps);
427 dtraceStartup(n_caps);
428 }
429
430 INLINE_HEADER void traceEventGcIdle(Capability *cap STG_UNUSED)
431 {
432 traceEvent(cap, EVENT_GC_IDLE);
433 dtraceGcIdle((EventCapNo)cap->no);
434 }
435
436 INLINE_HEADER void traceEventGcWork(Capability *cap STG_UNUSED)
437 {
438 traceEvent(cap, EVENT_GC_WORK);
439 dtraceGcWork((EventCapNo)cap->no);
440 }
441
442 INLINE_HEADER void traceEventGcDone(Capability *cap STG_UNUSED)
443 {
444 traceEvent(cap, EVENT_GC_DONE);
445 dtraceGcDone((EventCapNo)cap->no);
446 }
447
448 INLINE_HEADER void traceCapsetCreate(CapsetID capset STG_UNUSED,
449 CapsetType capset_type STG_UNUSED)
450 {
451 traceCapsetModify_(EVENT_CAPSET_CREATE, capset, capset_type);
452 dtraceCapsetCreate(capset, capset_type);
453 }
454
455 INLINE_HEADER void traceCapsetDelete(CapsetID capset STG_UNUSED)
456 {
457 traceCapsetModify_(EVENT_CAPSET_DELETE, capset, 0);
458 dtraceCapsetDelete(capset);
459 }
460
461 INLINE_HEADER void traceCapsetAssignCap(CapsetID capset STG_UNUSED,
462 nat capno STG_UNUSED)
463 {
464 traceCapsetModify_(EVENT_CAPSET_ASSIGN_CAP, capset, capno);
465 dtraceCapsetAssignCap(capset, capno);
466 }
467
468 INLINE_HEADER void traceCapsetRemoveCap(CapsetID capset STG_UNUSED,
469 nat capno STG_UNUSED)
470 {
471 traceCapsetModify_(EVENT_CAPSET_REMOVE_CAP, capset, capno);
472 dtraceCapsetRemoveCap(capset, capno);
473 }
474
475 INLINE_HEADER void traceOSProcessInfo(void)
476 {
477 traceOSProcessInfo_();
478 /* Note: no DTrace equivalent because all this OS process info
479 * is available to DTrace directly */
480 }
481
482 #include "EndPrivate.h"
483
484 #endif /* TRACE_H */