source: src/libcfa/concurrency/monitor.c @ afd550c

aaron-thesisarm-ehcleanup-dtorsdeferred_resndemanglerjacob/cs343-translationjenkins-sandboxnew-astnew-ast-unique-exprnew-envno_listpersistent-indexerwith_gc
Last change on this file since afd550c was afd550c, checked in by Thierry Delisle <tdelisle@…>, 4 years ago

Some more work on TLS macros

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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 -> TODO use a sort specialized for small numbers
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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