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 BEGIN_RTS_PRIVATE
  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
  31 #endif /* TRACING */
  32
  33 // -----------------------------------------------------------------------------
  34 // Message classes
  35 // -----------------------------------------------------------------------------
  36
  37 // debugging flags, set with +RTS -D<something>
  38 extern int DEBUG_sched;
  39 extern int DEBUG_interp;
  40 extern int DEBUG_weak;
  41 extern int DEBUG_gccafs;
  42 extern int DEBUG_gc;
  43 extern int DEBUG_block_alloc;
  44 extern int DEBUG_sanity;
  45 extern int DEBUG_stable;
  46 extern int DEBUG_stm;
  47 extern int DEBUG_prof;
  48 extern int DEBUG_gran;
  49 extern int DEBUG_par;
  50 extern int DEBUG_linker;
  51 extern int DEBUG_squeeze;
  52 extern int DEBUG_hpc;
  53 extern int DEBUG_sparks;
  54
  55 // events
  56 extern int TRACE_sched;
  57
  58 // -----------------------------------------------------------------------------
  59 // Posting events
  60 //
  61 // We use macros rather than inline functions deliberately.  We want
  62 // the not-taken case to be as efficient as possible, a simple
  63 // test-and-jump, and with inline functions gcc seemed to move some of
  64 // the instructions from the branch up before the test.
  65 //
  66 // -----------------------------------------------------------------------------
  67
  68 #ifdef DEBUG
  69 void traceBegin (const char *str, ...);
  70 void traceEnd (void);
  71 #endif
  72
  73 #ifdef TRACING
  74
  75 /*
  76  * Record a scheduler event
  77  */
  78 #define traceSchedEvent(cap, tag, tso, other)   \
  79     if (RTS_UNLIKELY(TRACE_sched)) {            \
  80         traceSchedEvent_(cap, tag, tso, other); \
  81     }
  82
  83 void traceSchedEvent_ (Capability *cap, EventTypeNum tag,
  84                        StgTSO *tso, StgWord64 other);
  85
  86
  87 /*
  88  * Record a nullary event
  89  */
  90 #define traceEvent(cap, tag)                    \
  91     if (RTS_UNLIKELY(TRACE_sched)) {            \
  92         traceEvent_(cap, tag);                  \
  93     }
  94
  95 void traceEvent_ (Capability *cap, EventTypeNum tag);
  96
  97 // variadic macros are C99, and supported by gcc.  However, the
  98 // ##__VA_ARGS syntax is a gcc extension, which allows the variable
  99 // argument list to be empty (see gcc docs for details).
 100
 101 /*
 102  * Emit a trace message on a particular Capability
 103  */
 104 #define traceCap(class, cap, msg, ...)          \
 105     if (RTS_UNLIKELY(class)) {                  \
 106         traceCap_(cap, msg, ##__VA_ARGS__);     \
 107     }
 108
 109 void traceCap_(Capability *cap, char *msg, ...);
 110
 111 /*
 112  * Emit a trace message
 113  */
 114 #define trace(class, msg, ...)                  \
 115     if (RTS_UNLIKELY(class)) {                  \
 116         trace_(msg, ##__VA_ARGS__);             \
 117     }
 118
 119 void trace_(char *msg, ...);
 120
 121 /*
 122  * A message or event emitted by the program
 123  */
 124 void traceUserMsg(Capability *cap, char *msg);
 125
 126 /*
 127  * Emit a debug message (only when DEBUG is defined)
 128  */
 129 #ifdef DEBUG
 130 #define debugTrace(class, msg, ...)             \
 131     if (RTS_UNLIKELY(class)) {                  \
 132         trace_(msg, ##__VA_ARGS__);             \
 133     }
 134 #else
 135 #define debugTrace(class, str, ...) /* nothing */
 136 #endif
 137
 138 /*
 139  * Emit a message/event describing the state of a thread
 140  */
 141 #define traceThreadStatus(class, tso)           \
 142     if (RTS_UNLIKELY(class)) {                  \
 143         traceThreadStatus_(tso);                \
 144     }
 145
 146 void traceThreadStatus_ (StgTSO *tso);
 147
 148 #else /* !TRACING */
 149
 150 #define traceSchedEvent(cap, tag, tso, other) /* nothing */
 151 #define traceEvent(cap, tag) /* nothing */
 152 #define traceCap(class, cap, msg, ...) /* nothing */
 153 #define trace(class, msg, ...) /* nothing */
 154 #define debugTrace(class, str, ...) /* nothing */
 155 #define traceThreadStatus(class, tso) /* nothing */
 156
 157 #endif /* TRACING */
 158
 159 // If DTRACE is enabled, but neither DEBUG nor TRACING, we need a C land
 160 // wrapper for the user-msg probe (as we can't expand that in PrimOps.cmm)
 161 //
 162 #if !defined(DEBUG) && !defined(TRACING) && defined(DTRACE)
 163
 164 void dtraceUserMsgWrapper(Capability *cap, char *msg);
 165
 166 #endif /* !defined(DEBUG) && !defined(TRACING) && defined(DTRACE) */
 167
 168 // -----------------------------------------------------------------------------
 169 // Aliases for static dtrace probes if dtrace is available
 170 // -----------------------------------------------------------------------------
 171
 172 #if defined(DTRACE)
 173
 174 #define dtraceCreateThread(cap, tid)                    \
 175     HASKELLEVENT_CREATE_THREAD(cap, tid)
 176 #define dtraceRunThread(cap, tid)                       \
 177     HASKELLEVENT_RUN_THREAD(cap, tid)
 178 #define dtraceStopThread(cap, tid, status)              \
 179     HASKELLEVENT_STOP_THREAD(cap, tid, status)
 180 #define dtraceThreadRunnable(cap, tid)                  \
 181     HASKELLEVENT_THREAD_RUNNABLE(cap, tid)
 182 #define dtraceMigrateThread(cap, tid, new_cap)          \
 183     HASKELLEVENT_MIGRATE_THREAD(cap, tid, new_cap)
 184 #define dtraceRunSpark(cap, tid)                        \
 185     HASKELLEVENT_RUN_SPARK(cap, tid)
 186 #define dtraceStealSpark(cap, tid, victim_cap)          \
 187     HASKELLEVENT_STEAL_SPARK(cap, tid, victim_cap)
 188 #define dtraceShutdown(cap)                             \
 189     HASKELLEVENT_SHUTDOWN(cap)
 190 #define dtraceThreadWakeup(cap, tid, other_cap)         \
 191     HASKELLEVENT_THREAD_WAKEUP(cap, tid, other_cap)
 192 #define dtraceGcStart(cap)                              \
 193     HASKELLEVENT_GC_START(cap)
 194 #define dtraceGcEnd(cap)                                \
 195     HASKELLEVENT_GC_END(cap)
 196 #define dtraceRequestSeqGc(cap)                         \
 197     HASKELLEVENT_REQUEST_SEQ_GC(cap)
 198 #define dtraceRequestParGc(cap)                         \
 199     HASKELLEVENT_REQUEST_PAR_GC(cap)
 200 #define dtraceCreateSparkThread(cap, spark_tid)         \
 201     HASKELLEVENT_CREATE_SPARK_THREAD(cap, spark_tid)
 202 #define dtraceStartup(num_caps)                         \
 203     HASKELLEVENT_STARTUP(num_caps)
 204 #define dtraceUserMsg(cap, msg)                         \
 205     HASKELLEVENT_USER_MSG(cap, msg)
 206 #define dtraceGcIdle(cap)                               \
 207     HASKELLEVENT_GC_IDLE(cap)
 208 #define dtraceGcWork(cap)                               \
 209     HASKELLEVENT_GC_WORK(cap)
 210 #define dtraceGcDone(cap)                               \
 211     HASKELLEVENT_GC_DONE(cap)
 212
 213 #else /* !defined(DTRACE) */
 214
 215 #define dtraceCreateThread(cap, tid)                    /* nothing */
 216 #define dtraceRunThread(cap, tid)                       /* nothing */
 217 #define dtraceStopThread(cap, tid, status)              /* nothing */
 218 #define dtraceThreadRunnable(cap, tid)                  /* nothing */
 219 #define dtraceMigrateThread(cap, tid, new_cap)          /* nothing */
 220 #define dtraceRunSpark(cap, tid)                        /* nothing */
 221 #define dtraceStealSpark(cap, tid, victim_cap)          /* nothing */
 222 #define dtraceShutdown(cap)                             /* nothing */
 223 #define dtraceThreadWakeup(cap, tid, other_cap)         /* nothing */
 224 #define dtraceGcStart(cap)                              /* nothing */
 225 #define dtraceGcEnd(cap)                                /* nothing */
 226 #define dtraceRequestSeqGc(cap)                         /* nothing */
 227 #define dtraceRequestParGc(cap)                         /* nothing */
 228 #define dtraceCreateSparkThread(cap, spark_tid)         /* nothing */
 229 #define dtraceStartup(num_caps)                         /* nothing */
 230 #define dtraceUserMsg(cap, msg)                         /* nothing */
 231 #define dtraceGcIdle(cap)                               /* nothing */
 232 #define dtraceGcWork(cap)                               /* nothing */
 233 #define dtraceGcDone(cap)                               /* nothing */
 234
 235 #endif
 236
 237 // -----------------------------------------------------------------------------
 238 // Trace probes dispatching to various tracing frameworks
 239 //
 240 // In order to avoid accumulating multiple calls to tracing calls at trace
 241 // points, we define inline probe functions that contain the various
 242 // invocations.
 243 //
 244 // Dtrace - dtrace probes are unconditionally added as probe activation is
 245 //   handled by the dtrace component of the kernel, and inactive probes are
 246 //   very cheap — usually, one no-op.  Consequently, dtrace can be used with
 247 //   all flavours of the RTS.  In addition, we still support logging events to
 248 //   a file, even in the presence of dtrace.  This is, eg, useful when tracing
 249 //   on a server, but browsing trace information with ThreadScope on a local
 250 //   client.
 251 //
 252 // -----------------------------------------------------------------------------
 253
 254 INLINE_HEADER void traceEventCreateThread(Capability *cap STG_UNUSED,
 255                                           StgTSO     *tso STG_UNUSED)
 256 {
 257     traceSchedEvent(cap, EVENT_CREATE_THREAD, tso, tso->stack_size);
 258     dtraceCreateThread((EventCapNo)cap->no, (EventThreadID)tso->id);
 259 }
 260
 261 INLINE_HEADER void traceEventRunThread(Capability *cap STG_UNUSED,
 262                                        StgTSO     *tso STG_UNUSED)
 263 {
 264     traceSchedEvent(cap, EVENT_RUN_THREAD, tso, tso->what_next);
 265     dtraceRunThread((EventCapNo)cap->no, (EventThreadID)tso->id);
 266 }
 267
 268 INLINE_HEADER void traceEventStopThread(Capability          *cap    STG_UNUSED,
 269                                         StgTSO              *tso    STG_UNUSED,
 270                                         StgThreadReturnCode  status STG_UNUSED)
 271 {
 272     traceSchedEvent(cap, EVENT_STOP_THREAD, tso, status);
 273     dtraceStopThread((EventCapNo)cap->no, (EventThreadID)tso->id,
 274                      (EventThreadStatus)status);
 275 }
 276
 277 // needs to be EXTERN_INLINE as it is used in another EXTERN_INLINE function
 278 EXTERN_INLINE void traceEventThreadRunnable(Capability *cap STG_UNUSED,
 279                                             StgTSO     *tso STG_UNUSED);
 280
 281 EXTERN_INLINE void traceEventThreadRunnable(Capability *cap STG_UNUSED,
 282                                             StgTSO     *tso STG_UNUSED)
 283 {
 284     traceSchedEvent(cap, EVENT_THREAD_RUNNABLE, tso, 0);
 285     dtraceThreadRunnable((EventCapNo)cap->no, (EventThreadID)tso->id);
 286 }
 287
 288 INLINE_HEADER void traceEventMigrateThread(Capability *cap     STG_UNUSED,
 289                                            StgTSO     *tso     STG_UNUSED,
 290                                            nat         new_cap STG_UNUSED)
 291 {
 292     traceSchedEvent(cap, EVENT_MIGRATE_THREAD, tso, new_cap);
 293     dtraceMigrateThread((EventCapNo)cap->no, (EventThreadID)tso->id,
 294                         (EventCapNo)new_cap);
 295 }
 296
 297 INLINE_HEADER void traceEventRunSpark(Capability *cap STG_UNUSED,
 298                                       StgTSO     *tso STG_UNUSED)
 299 {
 300     traceSchedEvent(cap, EVENT_RUN_SPARK, tso, 0);
 301     dtraceRunSpark((EventCapNo)cap->no, (EventThreadID)tso->id);
 302 }
 303
 304 INLINE_HEADER void traceEventStealSpark(Capability *cap        STG_UNUSED,
 305                                         StgTSO     *tso        STG_UNUSED,
 306                                         nat         victim_cap STG_UNUSED)
 307 {
 308     traceSchedEvent(cap, EVENT_STEAL_SPARK, tso, victim_cap);
 309     dtraceStealSpark((EventCapNo)cap->no, (EventThreadID)tso->id,
 310                      (EventCapNo)victim_cap);
 311 }
 312
 313 INLINE_HEADER void traceEventShutdown(Capability *cap STG_UNUSED)
 314 {
 315     traceSchedEvent(cap, EVENT_SHUTDOWN, 0, 0);
 316     dtraceShutdown((EventCapNo)cap->no);
 317 }
 318
 319 INLINE_HEADER void traceEventThreadWakeup(Capability *cap       STG_UNUSED,
 320                                           StgTSO     *tso       STG_UNUSED,
 321                                           nat         other_cap STG_UNUSED)
 322 {
 323     traceSchedEvent(cap, EVENT_THREAD_WAKEUP, tso, other_cap);
 324     dtraceThreadWakeup((EventCapNo)cap->no, (EventThreadID)tso->id,
 325                        (EventCapNo)other_cap);
 326 }
 327
 328 INLINE_HEADER void traceEventGcStart(Capability *cap STG_UNUSED)
 329 {
 330     traceSchedEvent(cap, EVENT_GC_START, 0, 0);
 331     dtraceGcStart((EventCapNo)cap->no);
 332 }
 333
 334 INLINE_HEADER void traceEventGcEnd(Capability *cap STG_UNUSED)
 335 {
 336     traceSchedEvent(cap, EVENT_GC_END, 0, 0);
 337     dtraceGcEnd((EventCapNo)cap->no);
 338 }
 339
 340 INLINE_HEADER void traceEventRequestSeqGc(Capability *cap STG_UNUSED)
 341 {
 342     traceSchedEvent(cap, EVENT_REQUEST_SEQ_GC, 0, 0);
 343     dtraceRequestSeqGc((EventCapNo)cap->no);
 344 }
 345
 346 INLINE_HEADER void traceEventRequestParGc(Capability *cap STG_UNUSED)
 347 {
 348     traceSchedEvent(cap, EVENT_REQUEST_PAR_GC, 0, 0);
 349     dtraceRequestParGc((EventCapNo)cap->no);
 350 }
 351
 352 INLINE_HEADER void traceEventCreateSparkThread(Capability  *cap      STG_UNUSED,
 353                                                StgThreadID spark_tid STG_UNUSED)
 354 {
 355     traceSchedEvent(cap, EVENT_CREATE_SPARK_THREAD, 0, spark_tid);
 356     dtraceCreateSparkThread((EventCapNo)cap->no, (EventThreadID)spark_tid);
 357 }
 358
 359 // This applies only to dtrace as EVENT_STARTUP in the logging framework is
 360 // handled specially in 'EventLog.c'.
 361 //
 362 INLINE_HEADER void dtraceEventStartup(void)
 363 {
 364 #ifdef THREADED_RTS
 365     // XXX n_capabilities hasn't been initislised yet
 366     dtraceStartup(RtsFlags.ParFlags.nNodes);
 367 #else
 368     dtraceStartup(1);
 369 #endif
 370 }
 371
 372 INLINE_HEADER void traceEventGcIdle(Capability *cap STG_UNUSED)
 373 {
 374     traceEvent(cap, EVENT_GC_IDLE);
 375     dtraceGcIdle((EventCapNo)cap->no);
 376 }
 377
 378 INLINE_HEADER void traceEventGcWork(Capability *cap STG_UNUSED)
 379 {
 380     traceEvent(cap, EVENT_GC_WORK);
 381     dtraceGcWork((EventCapNo)cap->no);
 382 }
 383
 384 INLINE_HEADER void traceEventGcDone(Capability *cap STG_UNUSED)
 385 {
 386     traceEvent(cap, EVENT_GC_DONE);
 387     dtraceGcDone((EventCapNo)cap->no);
 388 }
 389
 390 END_RTS_PRIVATE
 391
 392 #endif /* TRACE_H */