source: src/libcfa/concurrency/monitor.c@ 4f18de3

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors deferred_resn demangler enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr no_list persistent-indexer pthread-emulation qualifiedEnum
Last change on this file since 4f18de3 was 09800e9, checked in by Thierry Delisle <tdelisle@…>, 7 years ago

First draft at locks in Cforall
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File size: 28.9 KB
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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 : Fri Mar 30 14:30:26 2018
13// Update Count : 9
14//
15
16#include "monitor"
17
18#include <stdlib>
19#include <inttypes.h>
20
21#include "kernel_private.h"
22
23#include "bits/algorithms.h"
24
25//-----------------------------------------------------------------------------
26// Forward declarations
27static inline void set_owner ( monitor_desc * this, thread_desc * owner );
28static inline void set_owner ( monitor_desc * storage [], __lock_size_t count, thread_desc * owner );
29static inline void set_mask ( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask );
30static inline void reset_mask( monitor_desc * this );
31
32static inline thread_desc * next_thread( monitor_desc * this );
33static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & monitors );
34
35static inline void lock_all ( __spinlock_t * locks [], __lock_size_t count );
36static inline void lock_all ( monitor_desc * source [], __spinlock_t * /*out*/ locks [], __lock_size_t count );
37static inline void unlock_all( __spinlock_t * locks [], __lock_size_t count );
38static inline void unlock_all( monitor_desc * locks [], __lock_size_t count );
39
40static inline void save ( monitor_desc * ctx [], __lock_size_t count, __spinlock_t * locks [], unsigned int /*out*/ recursions [], __waitfor_mask_t /*out*/ masks [] );
41static inline void restore( monitor_desc * ctx [], __lock_size_t count, __spinlock_t * locks [], unsigned int /*in */ recursions [], __waitfor_mask_t /*in */ masks [] );
42
43static inline void init ( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] );
44static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] );
45
46static inline thread_desc * check_condition ( __condition_criterion_t * );
47static inline void brand_condition ( condition & );
48static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t &, monitor_desc * monitors [], __lock_size_t count );
49
50forall(dtype T | sized( T ))
51static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val );
52static inline __lock_size_t count_max ( const __waitfor_mask_t & mask );
53static inline __lock_size_t aggregate ( monitor_desc * storage [], const __waitfor_mask_t & mask );
54
55//-----------------------------------------------------------------------------
56// Useful defines
57#define wait_ctx(thrd, user_info) /* Create the necessary information to use the signaller stack */ \
58 __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \
59 __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \
60 init( count, monitors, waiter, criteria ); /* Link everything together */ \
61
62#define wait_ctx_primed(thrd, user_info) /* Create the necessary information to use the signaller stack */ \
63 __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \
64 __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \
65 init_push( count, monitors, waiter, criteria ); /* Link everything together and push it to the AS-Stack */ \
66
67#define monitor_ctx( mons, cnt ) /* Define that create the necessary struct for internal/external scheduling operations */ \
68 monitor_desc ** monitors = mons; /* Save the targeted monitors */ \
69 __lock_size_t count = cnt; /* Save the count to a local variable */ \
70 unsigned int recursions[ count ]; /* Save the current recursion levels to restore them later */ \
71 __waitfor_mask_t masks [ count ]; /* Save the current waitfor masks to restore them later */ \
72 __spinlock_t * locks [ count ]; /* We need to pass-in an array of locks to BlockInternal */ \
73
74#define monitor_save save ( monitors, count, locks, recursions, masks )
75#define monitor_restore restore( monitors, count, locks, recursions, masks )
76
77
78//-----------------------------------------------------------------------------
79// Enter/Leave routines
80
81
82extern "C" {
83 // Enter single monitor
84 static void __enter_monitor_desc( monitor_desc * this, const __monitor_group_t & group ) {
85 // Lock the monitor spinlock
86 lock( this->lock __cfaabi_dbg_ctx2 );
87 // Interrupts disable inside critical section
88 thread_desc * thrd = kernelTLS.this_thread;
89
90 __cfaabi_dbg_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 __cfaabi_dbg_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 __cfaabi_dbg_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 __cfaabi_dbg_print_safe( "Kernel : mon accepts \n" );
112 }
113 else {
114 __cfaabi_dbg_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
119 BlockInternal( &this->lock );
120
121 __cfaabi_dbg_print_safe( "Kernel : %10p Entered mon %p\n", thrd, this);
122
123 // BlockInternal will unlock spinlock, no need to unlock ourselves
124 return;
125 }
126
127 __cfaabi_dbg_print_safe( "Kernel : %10p Entered mon %p\n", thrd, this);
128
129 // Release the lock and leave
130 unlock( this->lock );
131 return;
132 }
133
134 static void __enter_monitor_dtor( monitor_desc * this, fptr_t func ) {
135 // Lock the monitor spinlock
136 lock( this->lock __cfaabi_dbg_ctx2 );
137 // Interrupts disable inside critical section
138 thread_desc * thrd = kernelTLS.this_thread;
139
140 __cfaabi_dbg_print_safe( "Kernel : %10p Entering dtor for mon %p (%p)\n", thrd, this, this->owner);
141
142
143 if( !this->owner ) {
144 __cfaabi_dbg_print_safe( "Kernel : Destroying free mon %p\n", this);
145
146 // No one has the monitor, just take it
147 set_owner( this, thrd );
148
149 unlock( this->lock );
150 return;
151 }
152 else if( this->owner == thrd) {
153 // We already have the monitor... but where about to destroy it so the nesting will fail
154 // Abort!
155 abort( "Attempt to destroy monitor %p by thread \"%.256s\" (%p) in nested mutex.", this, thrd->self_cor.name, thrd );
156 }
157
158 __lock_size_t count = 1;
159 monitor_desc ** monitors = &this;
160 __monitor_group_t group = { &this, 1, func };
161 if( is_accepted( this, group) ) {
162 __cfaabi_dbg_print_safe( "Kernel : mon accepts dtor, block and signal it \n" );
163
164 // Wake the thread that is waiting for this
165 __condition_criterion_t * urgent = pop( this->signal_stack );
166 verify( urgent );
167
168 // Reset mask
169 reset_mask( this );
170
171 // Create the node specific to this wait operation
172 wait_ctx_primed( thrd, 0 )
173
174 // Some one else has the monitor, wait for him to finish and then run
175 BlockInternal( &this->lock, urgent->owner->waiting_thread );
176
177 // Some one was waiting for us, enter
178 set_owner( this, thrd );
179 }
180 else {
181 __cfaabi_dbg_print_safe( "Kernel : blocking \n" );
182
183 wait_ctx( thrd, 0 )
184 this->dtor_node = &waiter;
185
186 // Some one else has the monitor, wait in line for it
187 append( this->entry_queue, thrd );
188 BlockInternal( &this->lock );
189
190 // BlockInternal will unlock spinlock, no need to unlock ourselves
191 return;
192 }
193
194 __cfaabi_dbg_print_safe( "Kernel : Destroying %p\n", this);
195
196 }
197
198 // Leave single monitor
199 void __leave_monitor_desc( monitor_desc * this ) {
200 // Lock the monitor spinlock
201 lock( this->lock __cfaabi_dbg_ctx2 );
202
203 __cfaabi_dbg_print_safe( "Kernel : %10p Leaving mon %p (%p)\n", kernelTLS.this_thread, this, this->owner);
204
205 verifyf( kernelTLS.this_thread == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", kernelTLS.this_thread, this->owner, this->recursion, this );
206
207 // Leaving a recursion level, decrement the counter
208 this->recursion -= 1;
209
210 // If we haven't left the last level of recursion
211 // it means we don't need to do anything
212 if( this->recursion != 0) {
213 __cfaabi_dbg_print_safe( "Kernel : recursion still %d\n", this->recursion);
214 unlock( this->lock );
215 return;
216 }
217
218 // Get the next thread, will be null on low contention monitor
219 thread_desc * new_owner = next_thread( this );
220
221 // We can now let other threads in safely
222 unlock( this->lock );
223
224 //We need to wake-up the thread
225 WakeThread( new_owner );
226 }
227
228 // Leave single monitor for the last time
229 void __leave_dtor_monitor_desc( monitor_desc * this ) {
230 __cfaabi_dbg_debug_do(
231 if( TL_GET( this_thread ) != this->owner ) {
232 abort( "Destroyed monitor %p has inconsistent owner, expected %p got %p.\n", this, TL_GET( this_thread ), this->owner);
233 }
234 if( this->recursion != 1 ) {
235 abort( "Destroyed monitor %p has %d outstanding nested calls.\n", this, this->recursion - 1);
236 }
237 )
238 }
239
240 // Leave the thread monitor
241 // last routine called by a thread.
242 // Should never return
243 void __leave_thread_monitor( thread_desc * thrd ) {
244 monitor_desc * this = &thrd->self_mon;
245
246 // Lock the monitor now
247 lock( this->lock __cfaabi_dbg_ctx2 );
248
249 disable_interrupts();
250
251 thrd->self_cor.state = Halted;
252
253 verifyf( thrd == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", thrd, this->owner, this->recursion, this );
254
255 // Leaving a recursion level, decrement the counter
256 this->recursion -= 1;
257
258 // If we haven't left the last level of recursion
259 // it must mean there is an error
260 if( this->recursion != 0) { abort( "Thread internal monitor has unbalanced recursion" ); }
261
262 // Fetch the next thread, can be null
263 thread_desc * new_owner = next_thread( this );
264
265 // Leave the thread, this will unlock the spinlock
266 // Use leave thread instead of BlockInternal which is
267 // specialized for this case and supports null new_owner
268 LeaveThread( &this->lock, new_owner );
269
270 // Control flow should never reach here!
271 }
272}
273
274// Enter multiple monitor
275// relies on the monitor array being sorted
276static inline void enter( __monitor_group_t monitors ) {
277 for( __lock_size_t i = 0; i < monitors.size; i++) {
278 __enter_monitor_desc( monitors[i], monitors );
279 }
280}
281
282// Leave multiple monitor
283// relies on the monitor array being sorted
284static inline void leave(monitor_desc * monitors [], __lock_size_t count) {
285 for( __lock_size_t i = count - 1; i >= 0; i--) {
286 __leave_monitor_desc( monitors[i] );
287 }
288}
289
290// Ctor for monitor guard
291// Sorts monitors before entering
292void ?{}( monitor_guard_t & this, monitor_desc * m [], __lock_size_t count, fptr_t func ) {
293 thread_desc * thrd = TL_GET( this_thread );
294
295 // Store current array
296 this.m = m;
297 this.count = count;
298
299 // Sort monitors based on address
300 __libcfa_small_sort(this.m, count);
301
302 // Save previous thread context
303 this.prev = thrd->monitors;
304
305 // Update thread context (needed for conditions)
306 (thrd->monitors){m, count, func};
307
308 // __cfaabi_dbg_print_safe( "MGUARD : enter %d\n", count);
309
310 // Enter the monitors in order
311 __monitor_group_t group = {this.m, this.count, func};
312 enter( group );
313
314 // __cfaabi_dbg_print_safe( "MGUARD : entered\n" );
315}
316
317
318// Dtor for monitor guard
319void ^?{}( monitor_guard_t & this ) {
320 // __cfaabi_dbg_print_safe( "MGUARD : leaving %d\n", this.count);
321
322 // Leave the monitors in order
323 leave( this.m, this.count );
324
325 // __cfaabi_dbg_print_safe( "MGUARD : left\n" );
326
327 // Restore thread context
328 TL_GET( this_thread )->monitors = this.prev;
329}
330
331// Ctor for monitor guard
332// Sorts monitors before entering
333void ?{}( monitor_dtor_guard_t & this, monitor_desc * m [], fptr_t func ) {
334 // optimization
335 thread_desc * thrd = TL_GET( this_thread );
336
337 // Store current array
338 this.m = *m;
339
340 // Save previous thread context
341 this.prev = thrd->monitors;
342
343 // Update thread context (needed for conditions)
344 (thrd->monitors){m, 1, func};
345
346 __enter_monitor_dtor( this.m, func );
347}
348
349// Dtor for monitor guard
350void ^?{}( monitor_dtor_guard_t & this ) {
351 // Leave the monitors in order
352 __leave_dtor_monitor_desc( this.m );
353
354 // Restore thread context
355 TL_GET( this_thread )->monitors = this.prev;
356}
357
358//-----------------------------------------------------------------------------
359// Internal scheduling types
360void ?{}(__condition_node_t & this, thread_desc * waiting_thread, __lock_size_t count, uintptr_t user_info ) {
361 this.waiting_thread = waiting_thread;
362 this.count = count;
363 this.next = NULL;
364 this.user_info = user_info;
365}
366
367void ?{}(__condition_criterion_t & this ) with( this ) {
368 ready = false;
369 target = NULL;
370 owner = NULL;
371 next = NULL;
372}
373
374void ?{}(__condition_criterion_t & this, monitor_desc * target, __condition_node_t & owner ) {
375 this.ready = false;
376 this.target = target;
377 this.owner = &owner;
378 this.next = NULL;
379}
380
381//-----------------------------------------------------------------------------
382// Internal scheduling
383void wait( condition & this, uintptr_t user_info = 0 ) {
384 brand_condition( this );
385
386 // Check that everything is as expected
387 assertf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors );
388 verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count );
389 verifyf( this.monitor_count < 32u, "Excessive monitor count (%"PRIiFAST16")", this.monitor_count );
390
391 // Create storage for monitor context
392 monitor_ctx( this.monitors, this.monitor_count );
393
394 // Create the node specific to this wait operation
395 wait_ctx( TL_GET( this_thread ), user_info );
396
397 // Append the current wait operation to the ones already queued on the condition
398 // We don't need locks for that since conditions must always be waited on inside monitor mutual exclusion
399 append( this.blocked, &waiter );
400
401 // Lock all monitors (aggregates the locks as well)
402 lock_all( monitors, locks, count );
403
404 // Find the next thread(s) to run
405 __lock_size_t thread_count = 0;
406 thread_desc * threads[ count ];
407 __builtin_memset( threads, 0, sizeof( threads ) );
408
409 // Save monitor states
410 monitor_save;
411
412 // Remove any duplicate threads
413 for( __lock_size_t i = 0; i < count; i++) {
414 thread_desc * new_owner = next_thread( monitors[i] );
415 insert_unique( threads, thread_count, new_owner );
416 }
417
418 // Everything is ready to go to sleep
419 BlockInternal( locks, count, threads, thread_count );
420
421 // We are back, restore the owners and recursions
422 monitor_restore;
423}
424
425bool signal( condition & this ) {
426 if( is_empty( this ) ) { return false; }
427
428 //Check that everything is as expected
429 verify( this.monitors );
430 verify( this.monitor_count != 0 );
431
432 //Some more checking in debug
433 __cfaabi_dbg_debug_do(
434 thread_desc * this_thrd = TL_GET( this_thread );
435 if ( this.monitor_count != this_thrd->monitors.size ) {
436 abort( "Signal on condition %p made with different number of monitor(s), expected %zi got %zi", &this, this.monitor_count, this_thrd->monitors.size );
437 }
438
439 for(int i = 0; i < this.monitor_count; i++) {
440 if ( this.monitors[i] != this_thrd->monitors[i] ) {
441 abort( "Signal on condition %p made with different monitor, expected %p got %p", &this, this.monitors[i], this_thrd->monitors[i] );
442 }
443 }
444 );
445
446 __lock_size_t count = this.monitor_count;
447
448 // Lock all monitors
449 lock_all( this.monitors, NULL, count );
450
451 //Pop the head of the waiting queue
452 __condition_node_t * node = pop_head( this.blocked );
453
454 //Add the thread to the proper AS stack
455 for(int i = 0; i < count; i++) {
456 __condition_criterion_t * crit = &node->criteria[i];
457 assert( !crit->ready );
458 push( crit->target->signal_stack, crit );
459 }
460
461 //Release
462 unlock_all( this.monitors, count );
463
464 return true;
465}
466
467bool signal_block( condition & this ) {
468 if( !this.blocked.head ) { return false; }
469
470 //Check that everything is as expected
471 verifyf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors );
472 verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count );
473
474 // Create storage for monitor context
475 monitor_ctx( this.monitors, this.monitor_count );
476
477 // Lock all monitors (aggregates the locks them as well)
478 lock_all( monitors, locks, count );
479
480
481 // Create the node specific to this wait operation
482 wait_ctx_primed( kernelTLS.this_thread, 0 )
483
484 //save contexts
485 monitor_save;
486
487 //Find the thread to run
488 thread_desc * signallee = pop_head( this.blocked )->waiting_thread;
489 set_owner( monitors, count, signallee );
490
491 __cfaabi_dbg_print_buffer_decl( "Kernel : signal_block condition %p (s: %p)\n", &this, signallee );
492
493 //Everything is ready to go to sleep
494 BlockInternal( locks, count, &signallee, 1 );
495
496
497 // WE WOKE UP
498
499
500 __cfaabi_dbg_print_buffer_local( "Kernel : signal_block returned\n" );
501
502 //We are back, restore the masks and recursions
503 monitor_restore;
504
505 return true;
506}
507
508// Access the user_info of the thread waiting at the front of the queue
509uintptr_t front( condition & this ) {
510 verifyf( !is_empty(this),
511 "Attempt to access user data on an empty condition.\n"
512 "Possible cause is not checking if the condition is empty before reading stored data."
513 );
514 return ((typeof(this.blocked.head))this.blocked.head)->user_info;
515}
516
517//-----------------------------------------------------------------------------
518// External scheduling
519// cases to handle :
520// - target already there :
521// block and wake
522// - dtor already there
523// put thread on signaller stack
524// - non-blocking
525// return else
526// - timeout
527// return timeout
528// - block
529// setup mask
530// block
531void __waitfor_internal( const __waitfor_mask_t & mask, int duration ) {
532 // This statment doesn't have a contiguous list of monitors...
533 // Create one!
534 __lock_size_t max = count_max( mask );
535 monitor_desc * mon_storage[max];
536 __builtin_memset( mon_storage, 0, sizeof( mon_storage ) );
537 __lock_size_t actual_count = aggregate( mon_storage, mask );
538
539 __cfaabi_dbg_print_buffer_decl( "Kernel : waitfor %"PRIdFAST16" (s: %"PRIdFAST16", m: %"PRIdFAST16")\n", actual_count, mask.size, (__lock_size_t)max);
540
541 if(actual_count == 0) return;
542
543 __cfaabi_dbg_print_buffer_local( "Kernel : waitfor internal proceeding\n" );
544
545 // Create storage for monitor context
546 monitor_ctx( mon_storage, actual_count );
547
548 // Lock all monitors (aggregates the locks as well)
549 lock_all( monitors, locks, count );
550
551 {
552 // Check if the entry queue
553 thread_desc * next; int index;
554 [next, index] = search_entry_queue( mask, monitors, count );
555
556 if( next ) {
557 *mask.accepted = index;
558 __acceptable_t& accepted = mask[index];
559 if( accepted.is_dtor ) {
560 __cfaabi_dbg_print_buffer_local( "Kernel : dtor already there\n" );
561 verifyf( accepted.size == 1, "ERROR: Accepted dtor has more than 1 mutex parameter." );
562
563 monitor_desc * mon2dtor = accepted[0];
564 verifyf( mon2dtor->dtor_node, "ERROR: Accepted monitor has no dtor_node." );
565
566 __condition_criterion_t * dtor_crit = mon2dtor->dtor_node->criteria;
567 push( mon2dtor->signal_stack, dtor_crit );
568
569 unlock_all( locks, count );
570 }
571 else {
572 __cfaabi_dbg_print_buffer_local( "Kernel : thread present, baton-passing\n" );
573
574 // Create the node specific to this wait operation
575 wait_ctx_primed( kernelTLS.this_thread, 0 );
576
577 // Save monitor states
578 monitor_save;
579
580 __cfaabi_dbg_print_buffer_local( "Kernel : baton of %"PRIdFAST16" monitors : ", count );
581 #ifdef __CFA_DEBUG_PRINT__
582 for( int i = 0; i < count; i++) {
583 __cfaabi_dbg_print_buffer_local( "%p %p ", monitors[i], monitors[i]->signal_stack.top );
584 }
585 #endif
586 __cfaabi_dbg_print_buffer_local( "\n" );
587
588 // Set the owners to be the next thread
589 set_owner( monitors, count, next );
590
591 // Everything is ready to go to sleep
592 BlockInternal( locks, count, &next, 1 );
593
594 // We are back, restore the owners and recursions
595 monitor_restore;
596
597 __cfaabi_dbg_print_buffer_local( "Kernel : thread present, returned\n" );
598 }
599
600 __cfaabi_dbg_print_buffer_local( "Kernel : accepted %d\n", *mask.accepted);
601 return;
602 }
603 }
604
605
606 if( duration == 0 ) {
607 __cfaabi_dbg_print_buffer_local( "Kernel : non-blocking, exiting\n" );
608
609 unlock_all( locks, count );
610
611 __cfaabi_dbg_print_buffer_local( "Kernel : accepted %d\n", *mask.accepted);
612 return;
613 }
614
615
616 verifyf( duration < 0, "Timeout on waitfor statments not supported yet." );
617
618 __cfaabi_dbg_print_buffer_local( "Kernel : blocking waitfor\n" );
619
620 // Create the node specific to this wait operation
621 wait_ctx_primed( kernelTLS.this_thread, 0 );
622
623 monitor_save;
624 set_mask( monitors, count, mask );
625
626 for( __lock_size_t i = 0; i < count; i++) {
627 verify( monitors[i]->owner == kernelTLS.this_thread );
628 }
629
630 //Everything is ready to go to sleep
631 BlockInternal( locks, count );
632
633
634 // WE WOKE UP
635
636
637 //We are back, restore the masks and recursions
638 monitor_restore;
639
640 __cfaabi_dbg_print_buffer_local( "Kernel : exiting\n" );
641
642 __cfaabi_dbg_print_buffer_local( "Kernel : accepted %d\n", *mask.accepted);
643}
644
645//-----------------------------------------------------------------------------
646// Utilities
647
648static inline void set_owner( monitor_desc * this, thread_desc * owner ) {
649 // __cfaabi_dbg_print_safe( "Kernal : Setting owner of %p to %p ( was %p)\n", this, owner, this->owner );
650
651 //Pass the monitor appropriately
652 this->owner = owner;
653
654 //We are passing the monitor to someone else, which means recursion level is not 0
655 this->recursion = owner ? 1 : 0;
656}
657
658static inline void set_owner( monitor_desc * monitors [], __lock_size_t count, thread_desc * owner ) {
659 monitors[0]->owner = owner;
660 monitors[0]->recursion = 1;
661 for( __lock_size_t i = 1; i < count; i++ ) {
662 monitors[i]->owner = owner;
663 monitors[i]->recursion = 0;
664 }
665}
666
667static inline void set_mask( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask ) {
668 for( __lock_size_t i = 0; i < count; i++) {
669 storage[i]->mask = mask;
670 }
671}
672
673static inline void reset_mask( monitor_desc * this ) {
674 this->mask.accepted = NULL;
675 this->mask.data = NULL;
676 this->mask.size = 0;
677}
678
679static inline thread_desc * next_thread( monitor_desc * this ) {
680 //Check the signaller stack
681 __cfaabi_dbg_print_safe( "Kernel : mon %p AS-stack top %p\n", this, this->signal_stack.top);
682 __condition_criterion_t * urgent = pop( this->signal_stack );
683 if( urgent ) {
684 //The signaller stack is not empty,
685 //regardless of if we are ready to baton pass,
686 //we need to set the monitor as in use
687 set_owner( this, urgent->owner->waiting_thread );
688
689 return check_condition( urgent );
690 }
691
692 // No signaller thread
693 // Get the next thread in the entry_queue
694 thread_desc * new_owner = pop_head( this->entry_queue );
695 set_owner( this, new_owner );
696
697 return new_owner;
698}
699
700static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & group ) {
701 __acceptable_t * it = this->mask.data; // Optim
702 __lock_size_t count = this->mask.size;
703
704 // Check if there are any acceptable functions
705 if( !it ) return false;
706
707 // If this isn't the first monitor to test this, there is no reason to repeat the test.
708 if( this != group[0] ) return group[0]->mask.accepted >= 0;
709
710 // For all acceptable functions check if this is the current function.
711 for( __lock_size_t i = 0; i < count; i++, it++ ) {
712 if( *it == group ) {
713 *this->mask.accepted = i;
714 return true;
715 }
716 }
717
718 // No function matched
719 return false;
720}
721
722static inline void init( __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 }
726
727 waiter.criteria = criteria;
728}
729
730static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ) {
731 for( __lock_size_t i = 0; i < count; i++) {
732 (criteria[i]){ monitors[i], waiter };
733 __cfaabi_dbg_print_safe( "Kernel : target %p = %p\n", criteria[i].target, &criteria[i] );
734 push( criteria[i].target->signal_stack, &criteria[i] );
735 }
736
737 waiter.criteria = criteria;
738}
739
740static inline void lock_all( __spinlock_t * locks [], __lock_size_t count ) {
741 for( __lock_size_t i = 0; i < count; i++ ) {
742 lock( *locks[i] __cfaabi_dbg_ctx2 );
743 }
744}
745
746static inline void lock_all( monitor_desc * source [], __spinlock_t * /*out*/ locks [], __lock_size_t count ) {
747 for( __lock_size_t i = 0; i < count; i++ ) {
748 __spinlock_t * l = &source[i]->lock;
749 lock( *l __cfaabi_dbg_ctx2 );
750 if(locks) locks[i] = l;
751 }
752}
753
754static inline void unlock_all( __spinlock_t * locks [], __lock_size_t count ) {
755 for( __lock_size_t i = 0; i < count; i++ ) {
756 unlock( *locks[i] );
757 }
758}
759
760static inline void unlock_all( monitor_desc * locks [], __lock_size_t count ) {
761 for( __lock_size_t i = 0; i < count; i++ ) {
762 unlock( locks[i]->lock );
763 }
764}
765
766static inline void save(
767 monitor_desc * ctx [],
768 __lock_size_t count,
769 __attribute((unused)) __spinlock_t * locks [],
770 unsigned int /*out*/ recursions [],
771 __waitfor_mask_t /*out*/ masks []
772) {
773 for( __lock_size_t i = 0; i < count; i++ ) {
774 recursions[i] = ctx[i]->recursion;
775 masks[i] = ctx[i]->mask;
776 }
777}
778
779static inline void restore(
780 monitor_desc * ctx [],
781 __lock_size_t count,
782 __spinlock_t * locks [],
783 unsigned int /*out*/ recursions [],
784 __waitfor_mask_t /*out*/ masks []
785) {
786 lock_all( locks, count );
787 for( __lock_size_t i = 0; i < count; i++ ) {
788 ctx[i]->recursion = recursions[i];
789 ctx[i]->mask = masks[i];
790 }
791 unlock_all( locks, count );
792}
793
794// Function has 2 different behavior
795// 1 - Marks a monitors as being ready to run
796// 2 - Checks if all the monitors are ready to run
797// if so return the thread to run
798static inline thread_desc * check_condition( __condition_criterion_t * target ) {
799 __condition_node_t * node = target->owner;
800 unsigned short count = node->count;
801 __condition_criterion_t * criteria = node->criteria;
802
803 bool ready2run = true;
804
805 for( int i = 0; i < count; i++ ) {
806
807 // __cfaabi_dbg_print_safe( "Checking %p for %p\n", &criteria[i], target );
808 if( &criteria[i] == target ) {
809 criteria[i].ready = true;
810 // __cfaabi_dbg_print_safe( "True\n" );
811 }
812
813 ready2run = criteria[i].ready && ready2run;
814 }
815
816 __cfaabi_dbg_print_safe( "Kernel : Runing %i (%p)\n", ready2run, ready2run ? node->waiting_thread : NULL );
817 return ready2run ? node->waiting_thread : NULL;
818}
819
820static inline void brand_condition( condition & this ) {
821 thread_desc * thrd = TL_GET( this_thread );
822 if( !this.monitors ) {
823 // __cfaabi_dbg_print_safe( "Branding\n" );
824 assertf( thrd->monitors.data != NULL, "No current monitor to brand condition %p", thrd->monitors.data );
825 this.monitor_count = thrd->monitors.size;
826
827 this.monitors = (monitor_desc **)malloc( this.monitor_count * sizeof( *this.monitors ) );
828 for( int i = 0; i < this.monitor_count; i++ ) {
829 this.monitors[i] = thrd->monitors[i];
830 }
831 }
832}
833
834static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t & mask, monitor_desc * monitors [], __lock_size_t count ) {
835
836 __queue_t(thread_desc) & entry_queue = monitors[0]->entry_queue;
837
838 // For each thread in the entry-queue
839 for( thread_desc ** thrd_it = &entry_queue.head;
840 *thrd_it;
841 thrd_it = &(*thrd_it)->next
842 ) {
843 // For each acceptable check if it matches
844 int i = 0;
845 __acceptable_t * end = end (mask);
846 __acceptable_t * begin = begin(mask);
847 for( __acceptable_t * it = begin; it != end; it++, i++ ) {
848 // Check if we have a match
849 if( *it == (*thrd_it)->monitors ) {
850
851 // If we have a match return it
852 // after removeing it from the entry queue
853 return [remove( entry_queue, thrd_it ), i];
854 }
855 }
856 }
857
858 return [0, -1];
859}
860
861forall(dtype T | sized( T ))
862static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val ) {
863 if( !val ) return size;
864
865 for( __lock_size_t i = 0; i <= size; i++) {
866 if( array[i] == val ) return size;
867 }
868
869 array[size] = val;
870 size = size + 1;
871 return size;
872}
873
874static inline __lock_size_t count_max( const __waitfor_mask_t & mask ) {
875 __lock_size_t max = 0;
876 for( __lock_size_t i = 0; i < mask.size; i++ ) {
877 __acceptable_t & accepted = mask[i];
878 max += accepted.size;
879 }
880 return max;
881}
882
883static inline __lock_size_t aggregate( monitor_desc * storage [], const __waitfor_mask_t & mask ) {
884 __lock_size_t size = 0;
885 for( __lock_size_t i = 0; i < mask.size; i++ ) {
886 __acceptable_t & accepted = mask[i];
887 __libcfa_small_sort( accepted.data, accepted.size );
888 for( __lock_size_t j = 0; j < accepted.size; j++) {
889 insert_unique( storage, size, accepted[j] );
890 }
891 }
892 // TODO insertion sort instead of this
893 __libcfa_small_sort( storage, size );
894 return size;
895}
896
897// Local Variables: //
898// mode: c //
899// tab-width: 4 //
900// End: //
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