summaryrefslogtreecommitdiff
path: root/sql/event_scheduler.cc
blob: a14700000daeb60d6765f97ffebef574a4d456a0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
/*
   Copyright (c) 2006, 2007 MySQL AB, 2008-2010 Sun Microsystems, Inc.
   Use is subject to license terms.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
*/

#include "mysql_priv.h"
#include "events.h"
#include "event_data_objects.h"
#include "event_scheduler.h"
#include "event_queue.h"
#include "event_db_repository.h"

/**
  @addtogroup Event_Scheduler
  @{
*/

#ifdef __GNUC__
#if __GNUC__ >= 2
#define SCHED_FUNC __FUNCTION__
#endif
#else
#define SCHED_FUNC "<unknown>"
#endif

#define LOCK_DATA()       lock_data(SCHED_FUNC, __LINE__)
#define UNLOCK_DATA()     unlock_data(SCHED_FUNC, __LINE__)
#define COND_STATE_WAIT(mythd, abstime, msg) \
        cond_wait(mythd, abstime, msg, SCHED_FUNC, __LINE__)

extern pthread_attr_t connection_attrib;


Event_db_repository *Event_worker_thread::db_repository;


static
const LEX_STRING scheduler_states_names[] =
{
  { C_STRING_WITH_LEN("INITIALIZED") },
  { C_STRING_WITH_LEN("RUNNING") },
  { C_STRING_WITH_LEN("STOPPING") }
};

struct scheduler_param {
  THD *thd;
  Event_scheduler *scheduler;
};


/*
  Prints the stack of infos, warnings, errors from thd to
  the console so it can be fetched by the logs-into-tables and
  checked later.

  SYNOPSIS
    evex_print_warnings
      thd  Thread used during the execution of the event
      et   The event itself
*/

void
Event_worker_thread::print_warnings(THD *thd, Event_job_data *et)
{
  MYSQL_ERROR *err;
  DBUG_ENTER("evex_print_warnings");
  if (!thd->warn_list.elements)
    DBUG_VOID_RETURN;

  char msg_buf[10 * STRING_BUFFER_USUAL_SIZE];
  char prefix_buf[5 * STRING_BUFFER_USUAL_SIZE];
  String prefix(prefix_buf, sizeof(prefix_buf), system_charset_info);
  prefix.length(0);
  prefix.append("Event Scheduler: [");

  prefix.append(et->definer.str, et->definer.length, system_charset_info);
  prefix.append("][", 2);
  prefix.append(et->dbname.str, et->dbname.length, system_charset_info);
  prefix.append('.');
  prefix.append(et->name.str, et->name.length, system_charset_info);
  prefix.append("] ", 2);

  List_iterator_fast<MYSQL_ERROR> it(thd->warn_list);
  while ((err= it++))
  {
    String err_msg(msg_buf, sizeof(msg_buf), system_charset_info);
    /* set it to 0 or we start adding at the end. That's the trick ;) */
    err_msg.length(0);
    err_msg.append(prefix);
    err_msg.append(err->msg, strlen(err->msg), system_charset_info);
    DBUG_ASSERT(err->level < 3);
    (sql_print_message_handlers[err->level])("%*s", err_msg.length(),
                                              err_msg.c_ptr_safe());
  }
  DBUG_VOID_RETURN;
}


/*
  Performs post initialization of structures in a new thread.

  SYNOPSIS
    post_init_event_thread()
      thd  Thread

  NOTES
      Before this is called, one should not do any DBUG_XXX() calls.

*/

bool
post_init_event_thread(THD *thd)
{
  (void) init_new_connection_handler_thread();
  if (init_thr_lock() || thd->store_globals())
  {
    thd->cleanup();
    return TRUE;
  }
  lex_start(thd);

  pthread_mutex_lock(&LOCK_thread_count);
  threads.append(thd);
  thread_count++;
  thread_running++;
  pthread_mutex_unlock(&LOCK_thread_count);

  return FALSE;
}


/*
  Cleans up the THD and the threaded environment of the thread.

  SYNOPSIS
    deinit_event_thread()
      thd  Thread
*/

void
deinit_event_thread(THD *thd)
{
  thd->proc_info= "Clearing";
  DBUG_ASSERT(thd->net.buff != 0);
  net_end(&thd->net);
  DBUG_PRINT("exit", ("Event thread finishing"));
  pthread_mutex_lock(&LOCK_thread_count);
  thread_count--;
  thread_running--;
  delete thd;
  pthread_cond_broadcast(&COND_thread_count);
  pthread_mutex_unlock(&LOCK_thread_count);
}


/*
  Performs pre- pthread_create() initialisation of THD. Do this
  in the thread that will pass THD to the child thread. In the
  child thread call post_init_event_thread().

  SYNOPSIS
    pre_init_event_thread()
      thd  The THD of the thread. Has to be allocated by the caller.

  NOTES
    1. The host of the thead is my_localhost
    2. thd->net is initted with NULL - no communication.
*/

void
pre_init_event_thread(THD* thd)
{
  DBUG_ENTER("pre_init_event_thread");
  thd->client_capabilities= 0;
  thd->security_ctx->master_access= 0;
  thd->security_ctx->db_access= 0;
  thd->security_ctx->host_or_ip= (char*)my_localhost;
  my_net_init(&thd->net, NULL);
  thd->security_ctx->set_user((char*)"event_scheduler");
  thd->net.read_timeout= slave_net_timeout;
  thd->slave_thread= 0;
  thd->options|= OPTION_AUTO_IS_NULL;
  thd->client_capabilities|= CLIENT_MULTI_RESULTS;
  pthread_mutex_lock(&LOCK_thread_count);
  thd->thread_id= thd->variables.pseudo_thread_id= thread_id++;
  pthread_mutex_unlock(&LOCK_thread_count);

  /*
    Guarantees that we will see the thread in SHOW PROCESSLIST though its
    vio is NULL.
  */

  thd->proc_info= "Initialized";
  thd->version= refresh_version;
  thd->set_time();

  DBUG_VOID_RETURN;
}


/*
  Function that executes the scheduler,

  SYNOPSIS
    event_scheduler_thread()
      arg  Pointer to `struct scheduler_param`

  RETURN VALUE
    0  OK
*/

pthread_handler_t
event_scheduler_thread(void *arg)
{
  /* needs to be first for thread_stack */
  THD *thd= (THD *) ((struct scheduler_param *) arg)->thd;
  Event_scheduler *scheduler= ((struct scheduler_param *) arg)->scheduler;
  bool res;

  thd->thread_stack= (char *)&thd;              // remember where our stack is
  res= post_init_event_thread(thd);

  DBUG_ENTER("event_scheduler_thread");
  my_free((char*)arg, MYF(0));
  if (!res)
    scheduler->run(thd);

  DBUG_LEAVE;                               // Against gcc warnings
  my_thread_end();
  return 0;
}


/**
  Function that executes an event in a child thread. Setups the
  environment for the event execution and cleans after that.

  SYNOPSIS
    event_worker_thread()
      arg  The Event_job_data object to be processed

  RETURN VALUE
    0  OK
*/

pthread_handler_t
event_worker_thread(void *arg)
{
  THD *thd;
  Event_queue_element_for_exec *event= (Event_queue_element_for_exec *)arg;

  thd= event->thd;

  Event_worker_thread worker_thread;
  worker_thread.run(thd, event);

  my_thread_end();
  return 0;                                     // Can't return anything here
}


/**
  Function that executes an event in a child thread. Setups the
  environment for the event execution and cleans after that.

  SYNOPSIS
    Event_worker_thread::run()
      thd    Thread context
      event  The Event_queue_element_for_exec object to be processed
*/

void
Event_worker_thread::run(THD *thd, Event_queue_element_for_exec *event)
{
  /* needs to be first for thread_stack */
  char my_stack;
  Event_job_data job_data;
  bool res;

  thd->thread_stack= &my_stack;                // remember where our stack is
  res= post_init_event_thread(thd);

  DBUG_ENTER("Event_worker_thread::run");
  DBUG_PRINT("info", ("Time is %ld, THD: 0x%lx", (long) my_time(0), (long) thd));

  if (res)
    goto end;

  if ((res= db_repository->load_named_event(thd, event->dbname, event->name,
                                            &job_data)))
  {
    DBUG_PRINT("error", ("Got error from load_named_event"));
    goto end;
  }

  thd->enable_slow_log= TRUE;

  res= job_data.execute(thd, event->dropped);

  print_warnings(thd, &job_data);

  if (res)
    sql_print_information("Event Scheduler: "
                          "[%s].[%s.%s] event execution failed.",
                          job_data.definer.str,
                          job_data.dbname.str, job_data.name.str);
end:
  DBUG_PRINT("info", ("Done with Event %s.%s", event->dbname.str,
             event->name.str));

  delete event;
  deinit_event_thread(thd);

  DBUG_VOID_RETURN;
}


Event_scheduler::Event_scheduler(Event_queue *queue_arg)
  :state(INITIALIZED),
  scheduler_thd(NULL),
  queue(queue_arg),
  mutex_last_locked_at_line(0),
  mutex_last_unlocked_at_line(0),
  mutex_last_locked_in_func("n/a"),
  mutex_last_unlocked_in_func("n/a"),
  mutex_scheduler_data_locked(FALSE),
  waiting_on_cond(FALSE),
  started_events(0)
{
  pthread_mutex_init(&LOCK_scheduler_state, MY_MUTEX_INIT_FAST);
  pthread_cond_init(&COND_state, NULL);

#ifdef SAFE_MUTEX
  /* Ensure right mutex order */
  pthread_mutex_lock(&LOCK_scheduler_state);
  pthread_mutex_lock(&LOCK_global_system_variables);
  pthread_mutex_unlock(&LOCK_global_system_variables);
  pthread_mutex_unlock(&LOCK_scheduler_state);
#endif
}


Event_scheduler::~Event_scheduler()
{
  stop();                                    /* does nothing if not running */
  pthread_mutex_destroy(&LOCK_scheduler_state);
  pthread_cond_destroy(&COND_state);
}


/*
  Starts the scheduler (again). Creates a new THD and passes it to
  a forked thread. Does not wait for acknowledgement from the new
  thread that it has started. Asynchronous starting. Most of the
  needed initializations are done in the current thread to minimize
  the chance of failure in the spawned thread.

  SYNOPSIS
    Event_scheduler::start()

  RETURN VALUE
    FALSE  OK
    TRUE   Error (not reported)
*/

bool
Event_scheduler::start()
{
  THD *new_thd= NULL;
  bool ret= FALSE;
  pthread_t th;
  struct scheduler_param *scheduler_param_value;
  DBUG_ENTER("Event_scheduler::start");

  LOCK_DATA();
  DBUG_PRINT("info", ("state before action %s", scheduler_states_names[state].str));
  if (state > INITIALIZED)
    goto end;

  if (!(new_thd= new THD))
  {
    sql_print_error("Event Scheduler: Cannot initialize the scheduler thread");
    ret= TRUE;
    goto end;
  }
  pre_init_event_thread(new_thd);
  new_thd->system_thread= SYSTEM_THREAD_EVENT_SCHEDULER;
  new_thd->command= COM_DAEMON;

  /*
    We should run the event scheduler thread under the super-user privileges.
    In particular, this is needed to be able to lock the mysql.event table
    for writing when the server is running in the read-only mode.
  */
  new_thd->security_ctx->master_access |= SUPER_ACL;

  scheduler_param_value=
    (struct scheduler_param *)my_malloc(sizeof(struct scheduler_param), MYF(0));
  scheduler_param_value->thd= new_thd;
  scheduler_param_value->scheduler= this;

  scheduler_thd= new_thd;
  DBUG_PRINT("info", ("Setting state go RUNNING"));
  state= RUNNING;
  DBUG_PRINT("info", ("Forking new thread for scheduler. THD: 0x%lx", (long) new_thd));
  if (pthread_create(&th, &connection_attrib, event_scheduler_thread,
                    (void*)scheduler_param_value))
  {
    DBUG_PRINT("error", ("cannot create a new thread"));
    state= INITIALIZED;
    scheduler_thd= NULL;
    ret= TRUE;

    new_thd->proc_info= "Clearing";
    DBUG_ASSERT(new_thd->net.buff != 0);
    net_end(&new_thd->net);
    pthread_mutex_lock(&LOCK_thread_count);
    thread_count--;
    thread_running--;
    delete new_thd;
    pthread_cond_broadcast(&COND_thread_count);
    pthread_mutex_unlock(&LOCK_thread_count);
  }
end:
  UNLOCK_DATA();

  DBUG_RETURN(ret);
}


/*
  The main loop of the scheduler.

  SYNOPSIS
    Event_scheduler::run()
      thd  Thread

  RETURN VALUE
    FALSE  OK
    TRUE   Error (Serious error)
*/

bool
Event_scheduler::run(THD *thd)
{
  int res= FALSE;
  DBUG_ENTER("Event_scheduler::run");

  sql_print_information("Event Scheduler: scheduler thread started with id %lu",
                        thd->thread_id);
  /*
    Recalculate the values in the queue because there could have been stops
    in executions of the scheduler and some times could have passed by.
  */
  queue->recalculate_activation_times(thd);

  while (is_running())
  {
    Event_queue_element_for_exec *event_name;

    /* Gets a minimized version */
    if (queue->get_top_for_execution_if_time(thd, &event_name))
    {
      sql_print_information("Event Scheduler: "
                            "Serious error during getting next "
                            "event to execute. Stopping");
      break;
    }

    DBUG_PRINT("info", ("get_top_for_execution_if_time returned "
                        "event_name=0x%lx", (long) event_name));
    if (event_name)
    {
      if ((res= execute_top(event_name)))
        break;
    }
    else
    {
      DBUG_ASSERT(thd->killed);
      DBUG_PRINT("info", ("job_data is NULL, the thread was killed"));
    }
    DBUG_PRINT("info", ("state=%s", scheduler_states_names[state].str));
  }

  LOCK_DATA();
  deinit_event_thread(thd);
  scheduler_thd= NULL;
  state= INITIALIZED;
  DBUG_PRINT("info", ("Signalling back to the stopper COND_state"));
  pthread_cond_signal(&COND_state);
  UNLOCK_DATA();

  DBUG_RETURN(res);
}


/*
  Creates a new THD instance and then forks a new thread, while passing
  the THD pointer and job_data to it.

  SYNOPSIS
    Event_scheduler::execute_top()

  RETURN VALUE
    FALSE  OK
    TRUE   Error (Serious error)
*/

bool
Event_scheduler::execute_top(Event_queue_element_for_exec *event_name)
{
  THD *new_thd;
  pthread_t th;
  int res= 0;
  DBUG_ENTER("Event_scheduler::execute_top");
  if (!(new_thd= new THD()))
    goto error;

  pre_init_event_thread(new_thd);
  new_thd->system_thread= SYSTEM_THREAD_EVENT_WORKER;
  event_name->thd= new_thd;
  DBUG_PRINT("info", ("Event %s@%s ready for start",
             event_name->dbname.str, event_name->name.str));

  /*
    TODO: should use thread pool here, preferably with an upper limit
    on number of threads: if too many events are scheduled for the
    same time, starting all of them at once won't help them run truly
    in parallel (because of the great amount of synchronization), so
    we may as well execute them in sequence, keeping concurrency at a
    reasonable level.
  */
  /* Major failure */
  if ((res= pthread_create(&th, &connection_attrib, event_worker_thread,
                           event_name)))
    goto error;

  ++started_events;

  DBUG_PRINT("info", ("Event is in THD: 0x%lx", (long) new_thd));
  DBUG_RETURN(FALSE);

error:
  DBUG_PRINT("error", ("Event_scheduler::execute_top() res: %d", res));
  if (new_thd)
  {
    new_thd->proc_info= "Clearing";
    DBUG_ASSERT(new_thd->net.buff != 0);
    net_end(&new_thd->net);
    pthread_mutex_lock(&LOCK_thread_count);
    thread_count--;
    thread_running--;
    delete new_thd;
    pthread_cond_broadcast(&COND_thread_count);
    pthread_mutex_unlock(&LOCK_thread_count);
  }
  delete event_name;
  DBUG_RETURN(TRUE);
}


/*
  Checks whether the state of the scheduler is RUNNING

  SYNOPSIS
    Event_scheduler::is_running()

  RETURN VALUE
    TRUE   RUNNING
    FALSE  Not RUNNING
*/

bool
Event_scheduler::is_running()
{
  LOCK_DATA();
  bool ret= (state == RUNNING);
  UNLOCK_DATA();
  return ret;
}


/**
  Stops the scheduler (again). Waits for acknowledgement from the
  scheduler that it has stopped - synchronous stopping.

  Already running events will not be stopped. If the user needs
  them stopped manual intervention is needed.

  SYNOPSIS
    Event_scheduler::stop()

  RETURN VALUE
    FALSE  OK
    TRUE   Error (not reported)
*/

bool
Event_scheduler::stop()
{
  THD *thd= current_thd;
  DBUG_ENTER("Event_scheduler::stop");
  DBUG_PRINT("enter", ("thd: 0x%lx", (long) thd));

  LOCK_DATA();
  DBUG_PRINT("info", ("state before action %s", scheduler_states_names[state].str));
  if (state != RUNNING)
    goto end;

  /* Guarantee we don't catch spurious signals */
  do {
    DBUG_PRINT("info", ("Waiting for COND_started_or_stopped from "
                        "the scheduler thread.  Current value of state is %s . "
                        "workers count=%d", scheduler_states_names[state].str,
                        workers_count()));
    /*
      NOTE: We don't use kill_one_thread() because it can't kill COM_DEAMON
      threads. In addition, kill_one_thread() requires THD but during shutdown
      current_thd is NULL. Hence, if kill_one_thread should be used it has to
      be modified to kill also daemons, by adding a flag, and also we have to
      create artificial THD here. To save all this work, we just do what
      kill_one_thread() does to kill a thread. See also sql_repl.cc for similar
      usage.
    */

    state= STOPPING;
    DBUG_PRINT("info", ("Scheduler thread has id %lu",
                        scheduler_thd->thread_id));
    /* Lock from delete */
    pthread_mutex_lock(&scheduler_thd->LOCK_thd_kill);
    /* This will wake up the thread if it waits on Queue's conditional */
    sql_print_information("Event Scheduler: Killing the scheduler thread, "
                          "thread id %lu",
                          scheduler_thd->thread_id);
    scheduler_thd->awake(KILL_CONNECTION);
    pthread_mutex_unlock(&scheduler_thd->LOCK_thd_kill);

    /* thd could be 0x0, when shutting down */
    sql_print_information("Event Scheduler: "
                          "Waiting for the scheduler thread to reply");

    /*
      Wait only 2 seconds, as there is a small chance the thread missed the
      above awake() call and we may have to do it again
    */
    struct timespec top_time;
    set_timespec(top_time, 2);
    COND_STATE_WAIT(thd, &top_time, "Waiting scheduler to stop");
  } while (state == STOPPING);
  DBUG_PRINT("info", ("Scheduler thread has cleaned up. Set state to INIT"));
  sql_print_information("Event Scheduler: Stopped");
end:
  UNLOCK_DATA();
  DBUG_RETURN(FALSE);
}


/*
  Returns the number of living event worker threads.

  SYNOPSIS
    Event_scheduler::workers_count()
*/

uint
Event_scheduler::workers_count()
{
  THD *tmp;
  uint count= 0;

  DBUG_ENTER("Event_scheduler::workers_count");
  pthread_mutex_lock(&LOCK_thread_count);       // For unlink from list
  I_List_iterator<THD> it(threads);
  while ((tmp=it++))
    if (tmp->system_thread == SYSTEM_THREAD_EVENT_WORKER)
      ++count;
  pthread_mutex_unlock(&LOCK_thread_count);
  DBUG_PRINT("exit", ("%d", count));
  DBUG_RETURN(count);
}


/*
  Auxiliary function for locking LOCK_scheduler_state. Used
  by the LOCK_DATA macro.

  SYNOPSIS
    Event_scheduler::lock_data()
      func  Which function is requesting mutex lock
      line  On which line mutex lock is requested
*/

void
Event_scheduler::lock_data(const char *func, uint line)
{
  DBUG_ENTER("Event_scheduler::lock_data");
  DBUG_PRINT("enter", ("func=%s line=%u", func, line));
  pthread_mutex_lock(&LOCK_scheduler_state);
  mutex_last_locked_in_func= func;
  mutex_last_locked_at_line= line;
  mutex_scheduler_data_locked= TRUE;
  DBUG_VOID_RETURN;
}


/*
  Auxiliary function for unlocking LOCK_scheduler_state. Used
  by the UNLOCK_DATA macro.

  SYNOPSIS
    Event_scheduler::unlock_data()
      func  Which function is requesting mutex unlock
      line  On which line mutex unlock is requested
*/

void
Event_scheduler::unlock_data(const char *func, uint line)
{
  DBUG_ENTER("Event_scheduler::unlock_data");
  DBUG_PRINT("enter", ("func=%s line=%u", func, line));
  mutex_last_unlocked_at_line= line;
  mutex_scheduler_data_locked= FALSE;
  mutex_last_unlocked_in_func= func;
  pthread_mutex_unlock(&LOCK_scheduler_state);
  DBUG_VOID_RETURN;
}


/*
  Wrapper for pthread_cond_wait/timedwait

  SYNOPSIS
    Event_scheduler::cond_wait()
      thd     Thread (Could be NULL during shutdown procedure)
      abstime If not null then call pthread_cond_timedwait()
      msg     Message for thd->proc_info
      func    Which function is requesting cond_wait
      line    On which line cond_wait is requested
*/

void
Event_scheduler::cond_wait(THD *thd, struct timespec *abstime, const char* msg,
                           const char *func, uint line)
{
  DBUG_ENTER("Event_scheduler::cond_wait");
  waiting_on_cond= TRUE;
  mutex_last_unlocked_at_line= line;
  mutex_scheduler_data_locked= FALSE;
  mutex_last_unlocked_in_func= func;
  if (thd)
    thd->enter_cond(&COND_state, &LOCK_scheduler_state, msg);

  DBUG_PRINT("info", ("pthread_cond_%swait", abstime? "timed":""));
  if (!abstime)
    pthread_cond_wait(&COND_state, &LOCK_scheduler_state);
  else
    pthread_cond_timedwait(&COND_state, &LOCK_scheduler_state, abstime);
  if (thd)
  {
    /*
      This will free the lock so we need to relock. Not the best thing to
      do but we need to obey cond_wait()
    */
    thd->exit_cond("");
    LOCK_DATA();
  }
  mutex_last_locked_in_func= func;
  mutex_last_locked_at_line= line;
  mutex_scheduler_data_locked= TRUE;
  waiting_on_cond= FALSE;
  DBUG_VOID_RETURN;
}


/*
  Dumps the internal status of the scheduler

  SYNOPSIS
    Event_scheduler::dump_internal_status()
*/

void
Event_scheduler::dump_internal_status()
{
  DBUG_ENTER("Event_scheduler::dump_internal_status");

  puts("");
  puts("Event scheduler status:");
  printf("State      : %s\n", scheduler_states_names[state].str);
  printf("Thread id  : %lu\n", scheduler_thd? scheduler_thd->thread_id : 0);
  printf("LLA        : %s:%u\n", mutex_last_locked_in_func,
                                 mutex_last_locked_at_line);
  printf("LUA        : %s:%u\n", mutex_last_unlocked_in_func,
                                 mutex_last_unlocked_at_line);
  printf("WOC        : %s\n", waiting_on_cond? "YES":"NO");
  printf("Workers    : %u\n", workers_count());
  printf("Executed   : %lu\n", (ulong) started_events);
  printf("Data locked: %s\n", mutex_scheduler_data_locked ? "YES":"NO");

  DBUG_VOID_RETURN;
}

/**
  @} (End of group Event_Scheduler)
*/