src/trace.h

   1 /*
   2  * Copyright (c) 2010-2013 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_APACHE_LICENSE_HEADER_START@
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  * @APPLE_APACHE_LICENSE_HEADER_END@
  19  */
  20
  21 /*
  22  * IMPORTANT: This header file describes INTERNAL interfaces to libdispatch
  23  * which are subject to change in future releases of Mac OS X. Any applications
  24  * relying on these interfaces WILL break.
  25  */
  26
  27 #ifndef __DISPATCH_TRACE__
  28 #define __DISPATCH_TRACE__
  29
  30 #if DISPATCH_PURE_C
  31
  32 #if DISPATCH_USE_DTRACE || DISPATCH_USE_DTRACE_INTROSPECTION
  33 typedef struct dispatch_trace_timer_params_s {
  34         int64_t deadline, interval, leeway;
  35 } *dispatch_trace_timer_params_t;
  36
  37 #include "provider.h"
  38 #endif // DISPATCH_USE_DTRACE || DISPATCH_USE_DTRACE_INTROSPECTION
  39
  40 #if DISPATCH_USE_DTRACE_INTROSPECTION
  41 #define _dispatch_trace_callout(_c, _f, _dcc) do { \
  42                 if (slowpath(DISPATCH_CALLOUT_ENTRY_ENABLED()) || \
  43                                 slowpath(DISPATCH_CALLOUT_RETURN_ENABLED())) { \
  44                         dispatch_queue_t _dq = _dispatch_queue_get_current(); \
  45                         const char *_label = _dq && _dq->dq_label ? _dq->dq_label : ""; \
  46                         dispatch_function_t _func = (dispatch_function_t)(_f); \
  47                         void *_ctxt = (_c); \
  48                         DISPATCH_CALLOUT_ENTRY(_dq, _label, _func, _ctxt); \
  49                         _dcc; \
  50                         DISPATCH_CALLOUT_RETURN(_dq, _label, _func, _ctxt); \
  51                 } else { \
  52                         _dcc; \
  53                 } \
  54         } while (0)
  55 #elif DISPATCH_INTROSPECTION
  56 #define _dispatch_trace_callout(_c, _f, _dcc) \
  57                 do { (void)(_c); (void)(_f); _dcc; } while (0)
  58 #endif // DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
  59
  60 #if DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
  61 DISPATCH_ALWAYS_INLINE
  62 static inline void
  63 _dispatch_trace_client_callout(void *ctxt, dispatch_function_t f)
  64 {
  65         dispatch_function_t func = (f == _dispatch_call_block_and_release &&
  66                         ctxt ? _dispatch_Block_invoke(ctxt) : f);
  67         _dispatch_introspection_callout_entry(ctxt, func);
  68         _dispatch_trace_callout(ctxt, func, _dispatch_client_callout(ctxt, f));
  69         _dispatch_introspection_callout_return(ctxt, func);
  70 }
  71
  72 DISPATCH_ALWAYS_INLINE
  73 static inline void
  74 _dispatch_trace_client_callout2(void *ctxt, size_t i, void (*f)(void *, size_t))
  75 {
  76         dispatch_function_t func = (dispatch_function_t)f;
  77         _dispatch_introspection_callout_entry(ctxt, func);
  78         _dispatch_trace_callout(ctxt, func, _dispatch_client_callout2(ctxt, i, f));
  79         _dispatch_introspection_callout_return(ctxt, func);
  80 }
  81
  82 #define _dispatch_client_callout                _dispatch_trace_client_callout
  83 #define _dispatch_client_callout2               _dispatch_trace_client_callout2
  84 #endif // DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
  85
  86 #if DISPATCH_USE_DTRACE_INTROSPECTION
  87 #define _dispatch_trace_continuation(_q, _o, _t) do { \
  88                 dispatch_queue_t _dq = (_q); \
  89                 const char *_label = _dq && _dq->dq_label ? _dq->dq_label : ""; \
  90                 struct dispatch_object_s *_do = (_o); \
  91                 dispatch_continuation_t _dc; \
  92                 char *_kind; \
  93                 dispatch_function_t _func; \
  94                 void *_ctxt; \
  95                 if (_dispatch_object_has_vtable(_do)) { \
  96                         _kind = (char*)dx_kind(_do); \
  97                         if ((dx_type(_do) & _DISPATCH_META_TYPE_MASK) == \
  98                                         _DISPATCH_SOURCE_TYPE && (_dq) != &_dispatch_mgr_q) { \
  99                                 dispatch_source_t _ds = (dispatch_source_t)_do; \
 100                                 _dc = os_atomic_load(&_ds->ds_refs->ds_handler[ \
 101                                                 DS_EVENT_HANDLER], relaxed); \
 102                                 _func = _dc ? _dc->dc_func : NULL; \
 103                                 _ctxt = _dc ? _dc->dc_ctxt : NULL; \
 104                         } else { \
 105                                 _func = (dispatch_function_t)_dispatch_queue_invoke; \
 106                                 _ctxt = _do->do_ctxt; \
 107                         } \
 108                 } else { \
 109                         _dc = (void*)_do; \
 110                         _ctxt = _dc->dc_ctxt; \
 111                         if (_dc->dc_flags & DISPATCH_OBJ_SYNC_SLOW_BIT) { \
 112                                 _kind = "semaphore"; \
 113                                 _func = (dispatch_function_t)dispatch_semaphore_signal; \
 114                         } else if (_dc->dc_flags & DISPATCH_OBJ_BLOCK_BIT) { \
 115                                 _kind = "block"; \
 116                                 _func = _dispatch_Block_invoke(_dc->dc_ctxt); \
 117                         } else { \
 118                                 _kind = "function"; \
 119                                 _func = _dc->dc_func; \
 120                         } \
 121                 } \
 122                 _t(_dq, _label, _do, _kind, _func, _ctxt); \
 123         } while (0)
 124 #elif DISPATCH_INTROSPECTION
 125 #define _dispatch_trace_continuation(_q, _o, _t) \
 126                 do { (void)(_q); (void)(_o); } while(0)
 127 #define DISPATCH_QUEUE_PUSH_ENABLED() 0
 128 #define DISPATCH_QUEUE_POP_ENABLED() 0
 129 #endif // DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
 130
 131 #if DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
 132 DISPATCH_ALWAYS_INLINE
 133 static inline void
 134 _dispatch_trace_queue_push_list(dispatch_queue_t dq, dispatch_object_t _head,
 135                 dispatch_object_t _tail, pthread_priority_t pp, unsigned int n)
 136 {
 137         if (slowpath(DISPATCH_QUEUE_PUSH_ENABLED())) {
 138                 struct dispatch_object_s *dou = _head._do;
 139                 do {
 140                         _dispatch_trace_continuation(dq, dou, DISPATCH_QUEUE_PUSH);
 141                 } while (dou != _tail._do && (dou = dou->do_next));
 142         }
 143         _dispatch_introspection_queue_push_list(dq, _head, _tail);
 144         _dispatch_queue_push_list(dq, _head, _tail, pp, n);
 145 }
 146
 147 DISPATCH_ALWAYS_INLINE
 148 static inline void
 149 _dispatch_trace_queue_push_inline(dispatch_queue_t dq, dispatch_object_t _tail,
 150                 pthread_priority_t pp, dispatch_wakeup_flags_t flags)
 151 {
 152         if (slowpath(DISPATCH_QUEUE_PUSH_ENABLED())) {
 153                 struct dispatch_object_s *dou = _tail._do;
 154                 _dispatch_trace_continuation(dq, dou, DISPATCH_QUEUE_PUSH);
 155         }
 156         _dispatch_introspection_queue_push(dq, _tail);
 157         _dispatch_queue_push_inline(dq, _tail, pp, flags);
 158 }
 159
 160 DISPATCH_ALWAYS_INLINE
 161 static inline void
 162 _dispatch_trace_continuation_push(dispatch_queue_t dq, dispatch_object_t _tail)
 163 {
 164         if (slowpath(DISPATCH_QUEUE_PUSH_ENABLED())) {
 165                 struct dispatch_object_s *dou = _tail._do;
 166                 _dispatch_trace_continuation(dq, dou, DISPATCH_QUEUE_PUSH);
 167         }
 168         _dispatch_introspection_queue_push(dq, _tail);
 169 }
 170
 171 #define _dispatch_queue_push_list _dispatch_trace_queue_push_list
 172 #define _dispatch_queue_push_inline _dispatch_trace_queue_push_inline
 173
 174 DISPATCH_ALWAYS_INLINE
 175 static inline void
 176 _dispatch_trace_continuation_pop(dispatch_queue_t dq, dispatch_object_t dou)
 177 {
 178         if (slowpath(DISPATCH_QUEUE_POP_ENABLED())) {
 179                 _dispatch_trace_continuation(dq, dou._do, DISPATCH_QUEUE_POP);
 180         }
 181         _dispatch_introspection_queue_pop(dq, dou);
 182 }
 183 #else
 184 #define _dispatch_trace_continuation_push(dq, dou) \
 185                 do { (void)(dq); (void)(dou); } while(0)
 186 #define _dispatch_trace_continuation_pop(dq, dou) \
 187                 do { (void)(dq); (void)(dou); } while(0)
 188 #endif // DISPATCH_USE_DTRACE_INTROSPECTION || DISPATCH_INTROSPECTION
 189
 190 #if DISPATCH_USE_DTRACE
 191 static inline dispatch_function_t
 192 _dispatch_trace_timer_function(dispatch_source_refs_t dr)
 193 {
 194         dispatch_continuation_t dc;
 195         dc = os_atomic_load(&dr->ds_handler[DS_EVENT_HANDLER], relaxed);
 196         return dc ? dc->dc_func : NULL;
 197 }
 198
 199 DISPATCH_ALWAYS_INLINE
 200 static inline dispatch_trace_timer_params_t
 201 _dispatch_trace_timer_params(dispatch_clock_t clock,
 202                 struct dispatch_timer_source_s *values, uint64_t deadline,
 203                 dispatch_trace_timer_params_t params)
 204 {
 205         #define _dispatch_trace_time2nano3(t) \
 206                         (clock == DISPATCH_CLOCK_MACH ? _dispatch_time_mach2nano(t) : (t))
 207         #define _dispatch_trace_time2nano2(v, t) ({ uint64_t _t = (t); \
 208                         (v) >= INT64_MAX ? -1ll : (int64_t)_dispatch_trace_time2nano3(_t);})
 209         #define _dispatch_trace_time2nano(v) ({ uint64_t _t; \
 210                         _t = _dispatch_trace_time2nano3(v); _t >= INT64_MAX ? -1ll : \
 211                         (int64_t)_t; })
 212         if (deadline) {
 213                 params->deadline = (int64_t)deadline;
 214         } else {
 215                 uint64_t now = _dispatch_time_now(clock);
 216                 params->deadline = _dispatch_trace_time2nano2(values->target,
 217                                 values->target < now ? 0 : values->target - now);
 218         }
 219         params->interval = _dispatch_trace_time2nano(values->interval);
 220         params->leeway = _dispatch_trace_time2nano(values->leeway);
 221         return params;
 222 }
 223
 224 DISPATCH_ALWAYS_INLINE
 225 static inline bool
 226 _dispatch_trace_timer_configure_enabled(void)
 227 {
 228         return slowpath(DISPATCH_TIMER_CONFIGURE_ENABLED());
 229 }
 230
 231 DISPATCH_ALWAYS_INLINE
 232 static inline void
 233 _dispatch_trace_timer_configure(dispatch_source_t ds, dispatch_clock_t clock,
 234                 struct dispatch_timer_source_s *values)
 235 {
 236         struct dispatch_trace_timer_params_s params;
 237         DISPATCH_TIMER_CONFIGURE(ds, _dispatch_trace_timer_function(ds->ds_refs),
 238                         _dispatch_trace_timer_params(clock, values, 0, &params));
 239 }
 240
 241 DISPATCH_ALWAYS_INLINE
 242 static inline void
 243 _dispatch_trace_timer_program(dispatch_source_refs_t dr, uint64_t deadline)
 244 {
 245         if (slowpath(DISPATCH_TIMER_PROGRAM_ENABLED())) {
 246                 if (deadline && dr) {
 247                         dispatch_source_t ds = _dispatch_source_from_refs(dr);
 248                         dispatch_clock_t clock = DISPATCH_TIMER_CLOCK(ds->ds_ident_hack);
 249                         struct dispatch_trace_timer_params_s params;
 250                         DISPATCH_TIMER_PROGRAM(ds, _dispatch_trace_timer_function(dr),
 251                                         _dispatch_trace_timer_params(clock, &ds_timer(dr),
 252                                         deadline, &params));
 253                 }
 254         }
 255 }
 256
 257 DISPATCH_ALWAYS_INLINE
 258 static inline void
 259 _dispatch_trace_timer_wake(dispatch_source_refs_t dr)
 260 {
 261         if (slowpath(DISPATCH_TIMER_WAKE_ENABLED())) {
 262                 if (dr) {
 263                         dispatch_source_t ds = _dispatch_source_from_refs(dr);
 264                         DISPATCH_TIMER_WAKE(ds, _dispatch_trace_timer_function(dr));
 265                 }
 266         }
 267 }
 268
 269 DISPATCH_ALWAYS_INLINE
 270 static inline void
 271 _dispatch_trace_timer_fire(dispatch_source_refs_t dr, unsigned long data,
 272                 unsigned long missed)
 273 {
 274         if (slowpath(DISPATCH_TIMER_FIRE_ENABLED())) {
 275                 if (!(data - missed) && dr) {
 276                         dispatch_source_t ds = _dispatch_source_from_refs(dr);
 277                         DISPATCH_TIMER_FIRE(ds, _dispatch_trace_timer_function(dr));
 278                 }
 279         }
 280 }
 281
 282 #else
 283
 284 #define _dispatch_trace_timer_configure_enabled() false
 285 #define _dispatch_trace_timer_configure(ds, clock, values) \
 286                 do { (void)(ds); (void)(clock); (void)(values); } while(0)
 287 #define _dispatch_trace_timer_program(dr, deadline) \
 288                 do { (void)(dr); (void)(deadline); } while(0)
 289 #define _dispatch_trace_timer_wake(dr) \
 290                 do { (void)(dr); } while(0)
 291 #define _dispatch_trace_timer_fire(dr, data, missed) \
 292                 do { (void)(dr); (void)(data); (void)(missed); } while(0)
 293
 294 #endif // DISPATCH_USE_DTRACE
 295
 296 #endif // DISPATCH_PURE_C
 297
 298 #endif // __DISPATCH_TRACE__