source: src/libcfa/concurrency/monitor.c@ 96fc67b

ADT arm-eh ast-experimental cleanup-dtors enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr pthread-emulation qualifiedEnum
Last change on this file since 96fc67b was 2f6a7e93, checked in by Rob Schluntz <rschlunt@…>, 8 years ago

Fix warnings in coroutine and monitor
  • Property mode set to 100644
File size: 29.1 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// monitor_desc.c --
8//
9// Author : Thierry Delisle
10// Created On : Thd Feb 23 12:27:26 2017
11// Last Modified By : Peter A. Buhr
12// Last Modified On : Mon Jul 31 14:59:05 2017
13// Update Count : 3
14//
15
16#include "monitor"
17
18#include <stdlib>
19#include <inttypes.h>
20
21#include "libhdr.h"
22#include "kernel_private.h"
23
24#include "bits/algorithms.h"
25
26//-----------------------------------------------------------------------------
27// Forward declarations
28static inline void set_owner ( monitor_desc * this, thread_desc * owner );
29static inline void set_owner ( monitor_desc * storage [], __lock_size_t count, thread_desc * owner );
30static inline void set_mask ( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask );
31static inline void reset_mask( monitor_desc * this );
32
33static inline thread_desc * next_thread( monitor_desc * this );
34static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & monitors );
35
36static inline void lock_all ( spinlock * locks [], __lock_size_t count );
37static inline void lock_all ( monitor_desc * source [], spinlock * /*out*/ locks [], __lock_size_t count );
38static inline void unlock_all( spinlock * locks [], __lock_size_t count );
39static inline void unlock_all( monitor_desc * locks [], __lock_size_t count );
40
41static inline void save ( monitor_desc * ctx [], __lock_size_t count, spinlock * locks [], unsigned int /*out*/ recursions [], __waitfor_mask_t /*out*/ masks [] );
42static inline void restore( monitor_desc * ctx [], __lock_size_t count, spinlock * locks [], unsigned int /*in */ recursions [], __waitfor_mask_t /*in */ masks [] );
43
44static inline void init ( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] );
45static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] );
46
47static inline thread_desc * check_condition ( __condition_criterion_t * );
48static inline void brand_condition ( condition & );
49static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t &, monitor_desc * monitors [], __lock_size_t count );
50
51forall(dtype T | sized( T ))
52static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val );
53static inline __lock_size_t count_max ( const __waitfor_mask_t & mask );
54static inline __lock_size_t aggregate ( monitor_desc * storage [], const __waitfor_mask_t & mask );
55
56//-----------------------------------------------------------------------------
57// Useful defines
58#define wait_ctx(thrd, user_info) /* Create the necessary information to use the signaller stack */ \
59 __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \
60 __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \
61 init( count, monitors, waiter, criteria ); /* Link everything together */ \
62
63#define wait_ctx_primed(thrd, user_info) /* Create the necessary information to use the signaller stack */ \
64 __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \
65 __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \
66 init_push( count, monitors, waiter, criteria ); /* Link everything together and push it to the AS-Stack */ \
67
68#define monitor_ctx( mons, cnt ) /* Define that create the necessary struct for internal/external scheduling operations */ \
69 monitor_desc ** monitors = mons; /* Save the targeted monitors */ \
70 __lock_size_t count = cnt; /* Save the count to a local variable */ \
71 unsigned int recursions[ count ]; /* Save the current recursion levels to restore them later */ \
72 __waitfor_mask_t masks [ count ]; /* Save the current waitfor masks to restore them later */ \
73 spinlock * locks [ count ]; /* We need to pass-in an array of locks to BlockInternal */ \
74
75#define monitor_save save ( monitors, count, locks, recursions, masks )
76#define monitor_restore restore( monitors, count, locks, recursions, masks )
77
78
79//-----------------------------------------------------------------------------
80// Enter/Leave routines
81
82
83extern "C" {
84 // Enter single monitor
85 static void __enter_monitor_desc( monitor_desc * this, const __monitor_group_t & group ) {
86 // Lock the monitor spinlock, lock_yield to reduce contention
87 lock_yield( &this->lock DEBUG_CTX2 );
88 thread_desc * thrd = this_thread;
89
90 LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entering mon %p (%p)\n", thrd, this, this->owner);
91
92 if( !this->owner ) {
93 // No one has the monitor, just take it
94 set_owner( this, thrd );
95
96 LIB_DEBUG_PRINT_SAFE("Kernel : mon is free \n");
97 }
98 else if( this->owner == thrd) {
99 // We already have the monitor, just note how many times we took it
100 this->recursion += 1;
101
102 LIB_DEBUG_PRINT_SAFE("Kernel : mon already owned \n");
103 }
104 else if( is_accepted( this, group) ) {
105 // Some one was waiting for us, enter
106 set_owner( this, thrd );
107
108 // Reset mask
109 reset_mask( this );
110
111 LIB_DEBUG_PRINT_SAFE("Kernel : mon accepts \n");
112 }
113 else {
114 LIB_DEBUG_PRINT_SAFE("Kernel : blocking \n");
115
116 // Some one else has the monitor, wait in line for it
117 append( this->entry_queue, thrd );
118 BlockInternal( &this->lock );
119
120 LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entered mon %p\n", thrd, this);
121
122 // BlockInternal will unlock spinlock, no need to unlock ourselves
123 return;
124 }
125
126 LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entered mon %p\n", thrd, this);
127
128 // Release the lock and leave
129 unlock( &this->lock );
130 return;
131 }
132
133 static void __enter_monitor_dtor( monitor_desc * this, fptr_t func ) {
134 // Lock the monitor spinlock, lock_yield to reduce contention
135 lock_yield( &this->lock DEBUG_CTX2 );
136 thread_desc * thrd = this_thread;
137
138 LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entering dtor for mon %p (%p)\n", thrd, this, this->owner);
139
140
141 if( !this->owner ) {
142 LIB_DEBUG_PRINT_SAFE("Kernel : Destroying free mon %p\n", this);
143
144 // No one has the monitor, just take it
145 set_owner( this, thrd );
146
147 unlock( &this->lock );
148 return;
149 }
150 else if( this->owner == thrd) {
151 // We already have the monitor... but where about to destroy it so the nesting will fail
152 // Abort!
153 abortf("Attempt to destroy monitor %p by thread \"%.256s\" (%p) in nested mutex.");
154 }
155
156 __lock_size_t count = 1;
157 monitor_desc ** monitors = &this;
158 __monitor_group_t group = { &this, 1, func };
159 if( is_accepted( this, group) ) {
160 LIB_DEBUG_PRINT_SAFE("Kernel : mon accepts dtor, block and signal it \n");
161
162 // Wake the thread that is waiting for this
163 __condition_criterion_t * urgent = pop( this->signal_stack );
164 verify( urgent );
165
166 // Reset mask
167 reset_mask( this );
168
169 // Create the node specific to this wait operation
170 wait_ctx_primed( this_thread, 0 )
171
172 // Some one else has the monitor, wait for him to finish and then run
173 BlockInternal( &this->lock, urgent->owner->waiting_thread );
174
175 // Some one was waiting for us, enter
176 set_owner( this, thrd );
177 }
178 else {
179 LIB_DEBUG_PRINT_SAFE("Kernel : blocking \n");
180
181 wait_ctx( this_thread, 0 )
182 this->dtor_node = &waiter;
183
184 // Some one else has the monitor, wait in line for it
185 append( this->entry_queue, thrd );
186 BlockInternal( &this->lock );
187
188 // BlockInternal will unlock spinlock, no need to unlock ourselves
189 return;
190 }
191
192 LIB_DEBUG_PRINT_SAFE("Kernel : Destroying %p\n", this);
193
194 }
195
196 // Leave single monitor
197 void __leave_monitor_desc( monitor_desc * this ) {
198 // Lock the monitor spinlock, lock_yield to reduce contention
199 lock_yield( &this->lock DEBUG_CTX2 );
200
201 LIB_DEBUG_PRINT_SAFE("Kernel : %10p Leaving mon %p (%p)\n", this_thread, this, this->owner);
202
203 verifyf( this_thread == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", this_thread, this->owner, this->recursion, this );
204
205 // Leaving a recursion level, decrement the counter
206 this->recursion -= 1;
207
208 // If we haven't left the last level of recursion
209 // it means we don't need to do anything
210 if( this->recursion != 0) {
211 LIB_DEBUG_PRINT_SAFE("Kernel : recursion still %d\n", this->recursion);
212 unlock( &this->lock );
213 return;
214 }
215
216 // Get the next thread, will be null on low contention monitor
217 thread_desc * new_owner = next_thread( this );
218
219 // We can now let other threads in safely
220 unlock( &this->lock );
221
222 //We need to wake-up the thread
223 WakeThread( new_owner );
224 }
225
226 // Leave single monitor for the last time
227 void __leave_dtor_monitor_desc( monitor_desc * this ) {
228 LIB_DEBUG_DO(
229 if( this_thread != this->owner ) {
230 abortf("Destroyed monitor %p has inconsistent owner, expected %p got %p.\n", this, this_thread, this->owner);
231 }
232 if( this->recursion != 1 ) {
233 abortf("Destroyed monitor %p has %d outstanding nested calls.\n", this, this->recursion - 1);
234 }
235 )
236 }
237
238 // Leave the thread monitor
239 // last routine called by a thread.
240 // Should never return
241 void __leave_thread_monitor( thread_desc * thrd ) {
242 monitor_desc * this = &thrd->self_mon;
243
244 // Lock the monitor now
245 lock_yield( &this->lock DEBUG_CTX2 );
246
247 disable_interrupts();
248
249 thrd->self_cor.state = Halted;
250
251 verifyf( thrd == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", thrd, this->owner, this->recursion, this );
252
253 // Leaving a recursion level, decrement the counter
254 this->recursion -= 1;
255
256 // If we haven't left the last level of recursion
257 // it must mean there is an error
258 if( this->recursion != 0) { abortf("Thread internal monitor has unbalanced recursion"); }
259
260 // Fetch the next thread, can be null
261 thread_desc * new_owner = next_thread( this );
262
263 // Leave the thread, this will unlock the spinlock
264 // Use leave thread instead of BlockInternal which is
265 // specialized for this case and supports null new_owner
266 LeaveThread( &this->lock, new_owner );
267
268 // Control flow should never reach here!
269 }
270}
271
272// Enter multiple monitor
273// relies on the monitor array being sorted
274static inline void enter( __monitor_group_t monitors ) {
275 for( __lock_size_t i = 0; i < monitors.size; i++) {
276 __enter_monitor_desc( monitors.list[i], monitors );
277 }
278}
279
280// Leave multiple monitor
281// relies on the monitor array being sorted
282static inline void leave(monitor_desc * monitors [], __lock_size_t count) {
283 for( __lock_size_t i = count - 1; i >= 0; i--) {
284 __leave_monitor_desc( monitors[i] );
285 }
286}
287
288// Ctor for monitor guard
289// Sorts monitors before entering
290void ?{}( monitor_guard_t & this, monitor_desc * m [], __lock_size_t count, fptr_t func ) {
291 // Store current array
292 this.m = m;
293 this.count = count;
294
295 // Sort monitors based on address -> TODO use a sort specialized for small numbers
296 __libcfa_small_sort(this.m, count);
297
298 // Save previous thread context
299 this.[prev_mntrs, prev_count, prev_func] = this_thread->monitors.[list, size, func];
300
301 // Update thread context (needed for conditions)
302 this_thread->monitors.[list, size, func] = [m, count, func];
303
304 // LIB_DEBUG_PRINT_SAFE("MGUARD : enter %d\n", count);
305
306 // Enter the monitors in order
307 __monitor_group_t group = {this.m, this.count, func};
308 enter( group );
309
310 // LIB_DEBUG_PRINT_SAFE("MGUARD : entered\n");
311}
312
313
314// Dtor for monitor guard
315void ^?{}( monitor_guard_t & this ) {
316 // LIB_DEBUG_PRINT_SAFE("MGUARD : leaving %d\n", this.count);
317
318 // Leave the monitors in order
319 leave( this.m, this.count );
320
321 // LIB_DEBUG_PRINT_SAFE("MGUARD : left\n");
322
323 // Restore thread context
324 this_thread->monitors.[list, size, func] = this.[prev_mntrs, prev_count, prev_func];
325}
326
327// Ctor for monitor guard
328// Sorts monitors before entering
329void ?{}( monitor_dtor_guard_t & this, monitor_desc * m [], fptr_t func ) {
330 // Store current array
331 this.m = *m;
332
333 // Save previous thread context
334 this.[prev_mntrs, prev_count, prev_func] = this_thread->monitors.[list, size, func];
335
336 // Update thread context (needed for conditions)
337 this_thread->monitors.[list, size, func] = [m, 1, func];
338
339 __enter_monitor_dtor( this.m, func );
340}
341
342// Dtor for monitor guard
343void ^?{}( monitor_dtor_guard_t & this ) {
344 // Leave the monitors in order
345 __leave_dtor_monitor_desc( this.m );
346
347 // Restore thread context
348 this_thread->monitors.[list, size, func] = this.[prev_mntrs, prev_count, prev_func];
349}
350
351//-----------------------------------------------------------------------------
352// Internal scheduling types
353void ?{}(__condition_node_t & this, thread_desc * waiting_thread, __lock_size_t count, uintptr_t user_info ) {
354 this.waiting_thread = waiting_thread;
355 this.count = count;
356 this.next = NULL;
357 this.user_info = user_info;
358}
359
360void ?{}(__condition_criterion_t & this ) {
361 this.ready = false;
362 this.target = NULL;
363 this.owner = NULL;
364 this.next = NULL;
365}
366
367void ?{}(__condition_criterion_t & this, monitor_desc * target, __condition_node_t & owner ) {
368 this.ready = false;
369 this.target = target;
370 this.owner = &owner;
371 this.next = NULL;
372}
373
374//-----------------------------------------------------------------------------
375// Internal scheduling
376void wait( condition & this, uintptr_t user_info = 0 ) {
377 brand_condition( this );
378
379 // Check that everything is as expected
380 assertf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors );
381 verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count );
382 verifyf( this.monitor_count < 32u, "Excessive monitor count (%"PRIiFAST16")", this.monitor_count );
383
384 // Create storage for monitor context
385 monitor_ctx( this.monitors, this.monitor_count );
386
387 // Create the node specific to this wait operation
388 wait_ctx( this_thread, user_info );
389
390 // Append the current wait operation to the ones already queued on the condition
391 // We don't need locks for that since conditions must always be waited on inside monitor mutual exclusion
392 append( this.blocked, &waiter );
393
394 // Lock all monitors (aggregates the locks as well)
395 lock_all( monitors, locks, count );
396
397 // Find the next thread(s) to run
398 __lock_size_t thread_count = 0;
399 thread_desc * threads[ count ];
400 __builtin_memset( threads, 0, sizeof( threads ) );
401
402 // Save monitor states
403 monitor_save;
404
405 // Remove any duplicate threads
406 for( __lock_size_t i = 0; i < count; i++) {
407 thread_desc * new_owner = next_thread( monitors[i] );
408 insert_unique( threads, thread_count, new_owner );
409 }
410
411 // Everything is ready to go to sleep
412 BlockInternal( locks, count, threads, thread_count );
413
414 // We are back, restore the owners and recursions
415 monitor_restore;
416}
417
418bool signal( condition & this ) {
419 if( is_empty( this ) ) { return false; }
420
421 //Check that everything is as expected
422 verify( this.monitors );
423 verify( this.monitor_count != 0 );
424
425 //Some more checking in debug
426 LIB_DEBUG_DO(
427 thread_desc * this_thrd = this_thread;
428 if ( this.monitor_count != this_thrd->monitors.size ) {
429 abortf( "Signal on condition %p made with different number of monitor(s), expected %i got %i", &this, this.monitor_count, this_thrd->monitors.size );
430 }
431
432 for(int i = 0; i < this.monitor_count; i++) {
433 if ( this.monitors[i] != this_thrd->monitors.list[i] ) {
434 abortf( "Signal on condition %p made with different monitor, expected %p got %i", &this, this.monitors[i], this_thrd->monitors.list[i] );
435 }
436 }
437 );
438
439 __lock_size_t count = this.monitor_count;
440
441 // Lock all monitors
442 lock_all( this.monitors, NULL, count );
443
444 //Pop the head of the waiting queue
445 __condition_node_t * node = pop_head( this.blocked );
446
447 //Add the thread to the proper AS stack
448 for(int i = 0; i < count; i++) {
449 __condition_criterion_t * crit = &node->criteria[i];
450 assert( !crit->ready );
451 push( crit->target->signal_stack, crit );
452 }
453
454 //Release
455 unlock_all( this.monitors, count );
456
457 return true;
458}
459
460bool signal_block( condition & this ) {
461 if( !this.blocked.head ) { return false; }
462
463 //Check that everything is as expected
464 verifyf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors );
465 verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count );
466
467 // Create storage for monitor context
468 monitor_ctx( this.monitors, this.monitor_count );
469
470 // Lock all monitors (aggregates the locks them as well)
471 lock_all( monitors, locks, count );
472
473 // Create the node specific to this wait operation
474 wait_ctx_primed( this_thread, 0 )
475
476 //save contexts
477 monitor_save;
478
479 //Find the thread to run
480 thread_desc * signallee = pop_head( this.blocked )->waiting_thread;
481 set_owner( monitors, count, signallee );
482
483 LIB_DEBUG_PRINT_BUFFER_DECL( "Kernel : signal_block condition %p (s: %p)\n", &this, signallee );
484
485 //Everything is ready to go to sleep
486 BlockInternal( locks, count, &signallee, 1 );
487
488
489 // WE WOKE UP
490
491
492 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : signal_block returned\n" );
493
494 //We are back, restore the masks and recursions
495 monitor_restore;
496
497 return true;
498}
499
500// Access the user_info of the thread waiting at the front of the queue
501uintptr_t front( condition & this ) {
502 verifyf( !is_empty(this),
503 "Attempt to access user data on an empty condition.\n"
504 "Possible cause is not checking if the condition is empty before reading stored data."
505 );
506 return this.blocked.head->user_info;
507}
508
509//-----------------------------------------------------------------------------
510// External scheduling
511// cases to handle :
512// - target already there :
513// block and wake
514// - dtor already there
515// put thread on signaller stack
516// - non-blocking
517// return else
518// - timeout
519// return timeout
520// - block
521// setup mask
522// block
523void __waitfor_internal( const __waitfor_mask_t & mask, int duration ) {
524 // This statment doesn't have a contiguous list of monitors...
525 // Create one!
526 __lock_size_t max = count_max( mask );
527 monitor_desc * mon_storage[max];
528 __builtin_memset( mon_storage, 0, sizeof( mon_storage ) );
529 __lock_size_t actual_count = aggregate( mon_storage, mask );
530
531 LIB_DEBUG_PRINT_BUFFER_DECL( "Kernel : waitfor %d (s: %d, m: %d)\n", actual_count, mask.size, (__lock_size_t)max);
532
533 if(actual_count == 0) return;
534
535 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : waitfor internal proceeding\n");
536
537 // Create storage for monitor context
538 monitor_ctx( mon_storage, actual_count );
539
540 // Lock all monitors (aggregates the locks as well)
541 lock_all( monitors, locks, count );
542
543 {
544 // Check if the entry queue
545 thread_desc * next; int index;
546 [next, index] = search_entry_queue( mask, monitors, count );
547
548 if( next ) {
549 *mask.accepted = index;
550 if( mask.clauses[index].is_dtor ) {
551 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : dtor already there\n");
552 verifyf( mask.clauses[index].size == 1 , "ERROR: Accepted dtor has more than 1 mutex parameter." );
553
554 monitor_desc * mon2dtor = mask.clauses[index].list[0];
555 verifyf( mon2dtor->dtor_node, "ERROR: Accepted monitor has no dtor_node." );
556
557 __condition_criterion_t * dtor_crit = mon2dtor->dtor_node->criteria;
558 push( mon2dtor->signal_stack, dtor_crit );
559
560 unlock_all( locks, count );
561 }
562 else {
563 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : thread present, baton-passing\n");
564
565 // Create the node specific to this wait operation
566 wait_ctx_primed( this_thread, 0 );
567
568 // Save monitor states
569 monitor_save;
570
571 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : baton of %d monitors : ", count );
572 #ifdef __CFA_DEBUG_PRINT__
573 for( int i = 0; i < count; i++) {
574 LIB_DEBUG_PRINT_BUFFER_LOCAL( "%p %p ", monitors[i], monitors[i]->signal_stack.top );
575 }
576 #endif
577 LIB_DEBUG_PRINT_BUFFER_LOCAL( "\n");
578
579 // Set the owners to be the next thread
580 set_owner( monitors, count, next );
581
582 // Everything is ready to go to sleep
583 BlockInternal( locks, count, &next, 1 );
584
585 // We are back, restore the owners and recursions
586 monitor_restore;
587
588 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : thread present, returned\n");
589 }
590
591 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted);
592
593 return;
594 }
595 }
596
597
598 if( duration == 0 ) {
599 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : non-blocking, exiting\n");
600
601 unlock_all( locks, count );
602
603 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted);
604 return;
605 }
606
607
608 verifyf( duration < 0, "Timeout on waitfor statments not supported yet.");
609
610 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : blocking waitfor\n");
611
612 // Create the node specific to this wait operation
613 wait_ctx_primed( this_thread, 0 );
614
615 monitor_save;
616 set_mask( monitors, count, mask );
617
618 for( __lock_size_t i = 0; i < count; i++) {
619 verify( monitors[i]->owner == this_thread );
620 }
621
622 //Everything is ready to go to sleep
623 BlockInternal( locks, count );
624
625
626 // WE WOKE UP
627
628
629 //We are back, restore the masks and recursions
630 monitor_restore;
631
632 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : exiting\n");
633
634 LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted);
635}
636
637//-----------------------------------------------------------------------------
638// Utilities
639
640static inline void set_owner( monitor_desc * this, thread_desc * owner ) {
641 // LIB_DEBUG_PRINT_SAFE("Kernal : Setting owner of %p to %p ( was %p)\n", this, owner, this->owner );
642
643 //Pass the monitor appropriately
644 this->owner = owner;
645
646 //We are passing the monitor to someone else, which means recursion level is not 0
647 this->recursion = owner ? 1 : 0;
648}
649
650static inline void set_owner( monitor_desc * monitors [], __lock_size_t count, thread_desc * owner ) {
651 monitors[0]->owner = owner;
652 monitors[0]->recursion = 1;
653 for( __lock_size_t i = 1; i < count; i++ ) {
654 monitors[i]->owner = owner;
655 monitors[i]->recursion = 0;
656 }
657}
658
659static inline void set_mask( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask ) {
660 for( __lock_size_t i = 0; i < count; i++) {
661 storage[i]->mask = mask;
662 }
663}
664
665static inline void reset_mask( monitor_desc * this ) {
666 this->mask.accepted = NULL;
667 this->mask.clauses = NULL;
668 this->mask.size = 0;
669}
670
671static inline thread_desc * next_thread( monitor_desc * this ) {
672 //Check the signaller stack
673 LIB_DEBUG_PRINT_SAFE("Kernel : mon %p AS-stack top %p\n", this, this->signal_stack.top);
674 __condition_criterion_t * urgent = pop( this->signal_stack );
675 if( urgent ) {
676 //The signaller stack is not empty,
677 //regardless of if we are ready to baton pass,
678 //we need to set the monitor as in use
679 set_owner( this, urgent->owner->waiting_thread );
680
681 return check_condition( urgent );
682 }
683
684 // No signaller thread
685 // Get the next thread in the entry_queue
686 thread_desc * new_owner = pop_head( this->entry_queue );
687 set_owner( this, new_owner );
688
689 return new_owner;
690}
691
692static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & group ) {
693 __acceptable_t * it = this->mask.clauses; // Optim
694 __lock_size_t count = this->mask.size;
695
696 // Check if there are any acceptable functions
697 if( !it ) return false;
698
699 // If this isn't the first monitor to test this, there is no reason to repeat the test.
700 if( this != group[0] ) return group[0]->mask.accepted >= 0;
701
702 // For all acceptable functions check if this is the current function.
703 for( __lock_size_t i = 0; i < count; i++, it++ ) {
704 if( *it == group ) {
705 *this->mask.accepted = i;
706 return true;
707 }
708 }
709
710 // No function matched
711 return false;
712}
713
714static inline void init( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ) {
715 for( __lock_size_t i = 0; i < count; i++) {
716 (criteria[i]){ monitors[i], waiter };
717 }
718
719 waiter.criteria = criteria;
720}
721
722static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ) {
723 for( __lock_size_t i = 0; i < count; i++) {
724 (criteria[i]){ monitors[i], waiter };
725 LIB_DEBUG_PRINT_SAFE( "Kernel : target %p = %p\n", criteria[i].target, &criteria[i] );
726 push( criteria[i].target->signal_stack, &criteria[i] );
727 }
728
729 waiter.criteria = criteria;
730}
731
732static inline void lock_all( spinlock * locks [], __lock_size_t count ) {
733 for( __lock_size_t i = 0; i < count; i++ ) {
734 lock_yield( locks[i] DEBUG_CTX2 );
735 }
736}
737
738static inline void lock_all( monitor_desc * source [], spinlock * /*out*/ locks [], __lock_size_t count ) {
739 for( __lock_size_t i = 0; i < count; i++ ) {
740 spinlock * l = &source[i]->lock;
741 lock_yield( l DEBUG_CTX2 );
742 if(locks) locks[i] = l;
743 }
744}
745
746static inline void unlock_all( spinlock * locks [], __lock_size_t count ) {
747 for( __lock_size_t i = 0; i < count; i++ ) {
748 unlock( locks[i] );
749 }
750}
751
752static inline void unlock_all( monitor_desc * locks [], __lock_size_t count ) {
753 for( __lock_size_t i = 0; i < count; i++ ) {
754 unlock( &locks[i]->lock );
755 }
756}
757
758static inline void save(
759 monitor_desc * ctx [],
760 __lock_size_t count,
761 __attribute((unused)) spinlock * locks [],
762 unsigned int /*out*/ recursions [],
763 __waitfor_mask_t /*out*/ masks []
764) {
765 for( __lock_size_t i = 0; i < count; i++ ) {
766 recursions[i] = ctx[i]->recursion;
767 masks[i] = ctx[i]->mask;
768 }
769}
770
771static inline void restore(
772 monitor_desc * ctx [],
773 __lock_size_t count,
774 spinlock * locks [],
775 unsigned int /*out*/ recursions [],
776 __waitfor_mask_t /*out*/ masks []
777) {
778 lock_all( locks, count );
779 for( __lock_size_t i = 0; i < count; i++ ) {
780 ctx[i]->recursion = recursions[i];
781 ctx[i]->mask = masks[i];
782 }
783 unlock_all( locks, count );
784}
785
786// Function has 2 different behavior
787// 1 - Marks a monitors as being ready to run
788// 2 - Checks if all the monitors are ready to run
789// if so return the thread to run
790static inline thread_desc * check_condition( __condition_criterion_t * target ) {
791 __condition_node_t * node = target->owner;
792 unsigned short count = node->count;
793 __condition_criterion_t * criteria = node->criteria;
794
795 bool ready2run = true;
796
797 for( int i = 0; i < count; i++ ) {
798
799 // LIB_DEBUG_PRINT_SAFE( "Checking %p for %p\n", &criteria[i], target );
800 if( &criteria[i] == target ) {
801 criteria[i].ready = true;
802 // LIB_DEBUG_PRINT_SAFE( "True\n" );
803 }
804
805 ready2run = criteria[i].ready && ready2run;
806 }
807
808 LIB_DEBUG_PRINT_SAFE( "Kernel : Runing %i (%p)\n", ready2run, ready2run ? node->waiting_thread : NULL );
809 return ready2run ? node->waiting_thread : NULL;
810}
811
812static inline void brand_condition( condition & this ) {
813 thread_desc * thrd = this_thread;
814 if( !this.monitors ) {
815 // LIB_DEBUG_PRINT_SAFE("Branding\n");
816 assertf( thrd->monitors.list != NULL, "No current monitor to brand condition %p", thrd->monitors.list );
817 this.monitor_count = thrd->monitors.size;
818
819 this.monitors = malloc( this.monitor_count * sizeof( *this.monitors ) );
820 for( int i = 0; i < this.monitor_count; i++ ) {
821 this.monitors[i] = thrd->monitors.list[i];
822 }
823 }
824}
825
826static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t & mask, monitor_desc * monitors [], __lock_size_t count ) {
827
828 __thread_queue_t & entry_queue = monitors[0]->entry_queue;
829
830 // For each thread in the entry-queue
831 for( thread_desc ** thrd_it = &entry_queue.head;
832 *thrd_it;
833 thrd_it = &(*thrd_it)->next
834 ) {
835 // For each acceptable check if it matches
836 int i = 0;
837 __acceptable_t * end = mask.clauses + mask.size;
838 for( __acceptable_t * it = mask.clauses; it != end; it++, i++ ) {
839 // Check if we have a match
840 if( *it == (*thrd_it)->monitors ) {
841
842 // If we have a match return it
843 // after removeing it from the entry queue
844 return [remove( entry_queue, thrd_it ), i];
845 }
846 }
847 }
848
849 return [0, -1];
850}
851
852forall(dtype T | sized( T ))
853static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val ) {
854 if( !val ) return size;
855
856 for( __lock_size_t i = 0; i <= size; i++) {
857 if( array[i] == val ) return size;
858 }
859
860 array[size] = val;
861 size = size + 1;
862 return size;
863}
864
865static inline __lock_size_t count_max( const __waitfor_mask_t & mask ) {
866 __lock_size_t max = 0;
867 for( __lock_size_t i = 0; i < mask.size; i++ ) {
868 max += mask.clauses[i].size;
869 }
870 return max;
871}
872
873static inline __lock_size_t aggregate( monitor_desc * storage [], const __waitfor_mask_t & mask ) {
874 __lock_size_t size = 0;
875 for( __lock_size_t i = 0; i < mask.size; i++ ) {
876 __libcfa_small_sort( mask.clauses[i].list, mask.clauses[i].size );
877 for( __lock_size_t j = 0; j < mask.clauses[i].size; j++) {
878 insert_unique( storage, size, mask.clauses[i].list[j] );
879 }
880 }
881 // TODO insertion sort instead of this
882 __libcfa_small_sort( storage, size );
883 return size;
884}
885
886void ?{}( __condition_blocked_queue_t & this ) {
887 this.head = NULL;
888 this.tail = &this.head;
889}
890
891void append( __condition_blocked_queue_t & this, __condition_node_t * c ) {
892 verify(this.tail != NULL);
893 *this.tail = c;
894 this.tail = &c->next;
895}
896
897__condition_node_t * pop_head( __condition_blocked_queue_t & this ) {
898 __condition_node_t * head = this.head;
899 if( head ) {
900 this.head = head->next;
901 if( !head->next ) {
902 this.tail = &this.head;
903 }
904 head->next = NULL;
905 }
906 return head;
907}
908
909// Local Variables: //
910// mode: c //
911// tab-width: 4 //
912// End: //
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