0 branches 0 tags
74
Remove redundent coroutines guard
jonroach 29 Dec 2025 16:08
1 contributor
1101 lines29.3 KB
Newer
Older
Text Raw Blame
  • Delete
-
+
commited
{line.log.rev}
 on
8 months ago
4
1
 #include "coroutine.h"
2
 #include <assert.h>
3
 #include <setjmp.h>
4
 #include <stdbool.h>
5
 #include <stddef.h>
5 months ago
6
 #include <stdio.h>
7 months ago
7
 #include "cor_platform.h"
8 months ago
4
8
6 months ago
9
 // see CPython again, this time from ctypes.h
10
 #if (defined (__SVR4) && defined (__sun)) || defined(COROUTINE_HAVE_ALLOCA_H)
11
 # include <alloca.h>
12
 #elif defined(MS_WIN32)
13
 # include <malloc.h>
14
 #endif
8 months ago
4
15
6 months ago
16
 /* If the system does not define alloca(), we have to hope for a compiler builtin. */
17
 #ifndef alloca
18
 # if defined __GNUC__ || (__clang_major__ >= 4)
19
 # define alloca __builtin_alloca
20
 # else
21
 # error "Could not define alloca() on your platform."
22
 # endif
23
 #endif
24
7 months ago
25
 static void Coroutine_RunNext(void);
7 months ago
26
 static void _Coroutine_Continue(Coroutine *cor, void *value, bool early);
6 months ago
27
 static unsigned char *StackTopNow(void);
8 months ago
28
8 months ago
4
29
 ///////////////////////////////////////////////////////////////////////////////
30
 // 2-way linked lists...
31
 //
8 months ago
32
 // Brought inline here to avoid namespace polution
8 months ago
4
33
 ///////////////////////////////////////////////////////////////////////////////
34
35
 typedef struct List_Link List_Link;
36
 struct List_Link {
37
 List_Link *next;
38
 List_Link *prev;
39
 };
40
41
 typedef struct List_Head List_Head;
42
 struct List_Head {
43
 union {
44
 struct {
45
 List_Link link;
46
 List_Link *filler;
47
 } fwd;
48
 struct {
49
 List_Link *filler;
50
 List_Link link;
51
 } back;
52
 };
53
 };
54
8 months ago
55
56
 static inline bool List_IsEmpty(
57
 const List_Head *list
58
 ){
8 months ago
4
59
 return list->fwd.link.next == &list->back.link;
60
 }
61
8 months ago
62
63
 static inline List_Link *List_GetHead(
64
 const List_Head *list
65
 ){
8 months ago
4
66
 return List_IsEmpty(list) ? NULL : list->fwd.link.next;
67
 }
8 months ago
68
69
5 months ago
70
 static inline List_Link *List_Begin(
71
 const List_Head *list
72
 ){
73
 return list->fwd.link.next;
74
 }
75
76
77
 static inline bool Link_NextIsLink(
78
 const List_Link *link
79
 ){
80
 return link->next != NULL;
81
 }
82
83
84
 static inline List_Link *Link_Next(
85
 List_Link *link
86
 ){
87
 return link->next;
88
 }
89
90
91
 static inline bool Link_PrevIsLink(
92
 const List_Link *link
93
 ){
94
 return link->prev != NULL;
95
 }
96
97
98
 static inline List_Link *Link_Prev(
99
 List_Link *link
100
 ){
101
 return link->prev;
102
 }
103
5 months ago
104
 static inline List_Link *List_GetTail(
105
 const List_Head *list
106
 ){
107
 return List_IsEmpty(list) ? NULL : list->back.link.prev;
108
 }
8 months ago
109
110
8 months ago
4
111
 #define OFFSETOF(Container, Field) ((char *)&((Container *)4)->Field - (char *)(Container *)4)
112
 #define List_Link_Container(Container, Link, link) ((Container *)((char *)(link) - OFFSETOF(Container, Link)))
113
8 months ago
114
115
 static inline void List_Init(
116
 List_Head *list
117
 ){
8 months ago
4
118
 list->fwd.link.next = &list->back.link;
119
 list->fwd.link.prev = NULL;
120
 list->back.link.prev = &list->fwd.link;
121
 }
122
8 months ago
123
5 months ago
124
 static inline void Link_AddAfter(
125
 List_Link *link,
126
 List_Link *after
127
 ){
128
 link->next = after->next;
129
 link->prev = after;
130
 after->next->prev = link;
131
 after->next = link;
132
 }
133
134
8 months ago
135
 static inline void List_AddHead(
136
 List_Head *list,
137
 List_Link *link
138
 ){
5 months ago
139
 Link_AddAfter(link, &list->fwd.link);
8 months ago
4
140
 }
141
8 months ago
142
5 months ago
143
 static inline void Link_AddBefore(
144
 List_Link *link,
145
 List_Link *before
146
 ){
147
 link->prev = before->prev;
148
 link->next = before;
149
 before->prev->next = link;
150
 before->prev = link;
151
 }
152
153
8 months ago
154
 static inline void List_AddTail(
155
 List_Head *list,
156
 List_Link *link
157
 ){
5 months ago
158
 Link_AddBefore(link, &list->back.link);
8 months ago
4
159
 }
160
8 months ago
161
5 months ago
162
 static inline void Link_Remove(
8 months ago
163
 List_Link *link
164
 ){
8 months ago
4
165
 link->prev->next = link->next;
166
 link->next->prev = link->prev;
167
 }
168
169
 ///////////////////////////////////////////////////////////////////////////////
170
 // ...2-way linked lists
171
 ///////////////////////////////////////////////////////////////////////////////
172
8 months ago
173
 typedef struct Coroutines Coroutines;
8 months ago
4
174
175
 enum {
176
 Coroutines_Starting,
177
 Coroutines_Started,
178
 Coroutines_Active,
179
 Coroutines_Stopping
180
 };
181
182
 enum {
183
 Chunk_Initial,
184
 Chunk_Create,
5 months ago
185
 Chunk_Split,
8 months ago
4
186
 Chunk_Enter
187
 };
188
8 months ago
189
 typedef enum Coroutine_State {
8 months ago
4
190
 Coroutine_Free,
191
 Coroutine_Idle,
192
 Coroutine_Running,
193
 Coroutine_Waiting,
194
 Coroutine_Complete
8 months ago
195
 } Coroutine_State;
8 months ago
4
196
197
 enum {
198
 Coroutines_Init,
199
 Coroutines_AllocatedChunk,
200
 Coroutines_CoroutineComplete,
201
 };
202
203
 struct Coroutine {
6 months ago
204
 Coroutines *coroutines; // so can work with it off-thread
205
 List_Link link; // for whichever list it's on
5 months ago
206
 List_Link all_link; // list of all Coroutines
6 months ago
207
 jmp_buf buf; // how to get back to it
5 months ago
208
 unsigned char *prev_limit; // the previous Coroutine's stack limit
209
 unsigned char *base; // where the base (high address) of this Coroutine's stack is
210
 unsigned char *limit; // where the limit (low address) of this Coroutine's stack is
6 months ago
211
 unsigned char *guard; // where the stack overrun guard is
5 months ago
212
 size_t size;
6 months ago
213
 Coroutine_Start start; // entry point
214
 void *entry_param; // to pass to start
215
 void *value; // yielded/returned
216
 unsigned char *stack_top; // recorded at yield
8 months ago
217
 Coroutine_State state;
8 months ago
4
218
 };
219
220
 struct Coroutines {
7 months ago
221
 _Cor_Mutex mutex;
8 months ago
222
 jmp_buf controller; // to return from Coroutine_Run
223
 jmp_buf chunk_allocated;// for chunk allocation
5 months ago
224
 size_t gap_before; // bytes between previous's stack_top and next's Coroutine
225
 size_t gap_after; // bytes between Coroutine and stack_base
8 months ago
4
226
227
 // singletons
228
 Coroutine *tip; // top of stack chunk
229
 Coroutine *active; // currently running coroutine
230
 Coroutine *primary; // Coroutine_Run coroutine
6 months ago
231
 unsigned char *stack_limit; // when not NULL, where the stack finishes
8 months ago
4
232
233
 // lists
5 months ago
234
 List_Head all; // all Coroutines (in address order)
235
 List_Head free; // free Coroutines
8 months ago
4
236
 List_Head inactive; // idle or complete
237
 List_Head runable; // running or waiting to run
238
 List_Head waiting; // yielded / waiting to run
7 months ago
239
 _Cor_Mutex waiting_mutex;
8 months ago
4
240
8 months ago
241
 // Summary of the system
242
 Coroutine_Report report;
243
8 months ago
4
244
 // state
245
 char state;
246
 };
247
5 months ago
248
 _Cor_thread_local Coroutines *g_c;
8 months ago
4
249
5 months ago
250
 static void ReserveStackSpace(Coroutines *cors, Coroutine *parent, size_t chunk_size, unsigned char *childs_limit);
5 months ago
251
 static void stack_chunk_base(Coroutines *cors, Coroutine *parent, unsigned char *prev_limit, unsigned char *limit);
8 months ago
4
252
8 months ago
253
6 months ago
254
 #define GUARD_PATTERN_SIZE (4)
8 months ago
255
 // Check whether the guard is intact
256
 static inline bool Check_Guard(
257
 unsigned char *guard
258
 ){
6 months ago
259
 return !guard ||
260
 (guard[0] == 0xde &&
261
 guard[1] == 0xad &&
262
 guard[2] == 0xbe &&
263
 guard[3] == 0xef);
8 months ago
264
 }
265
266
6 months ago
267
 static inline void Apply_Guard(unsigned char *guard){
268
 guard[0] = 0xde;
269
 guard[1] = 0xad;
270
 guard[2] = 0xbe;
271
 guard[3] = 0xef;
272
 }
273
274
5 months ago
275
 static bool Coroutine_StackHasOverrun(void){
6 months ago
276
 unsigned char *stack_top = StackTopNow();
5 months ago
277
 unsigned char *stack_limit = g_c ? g_c->stack_limit : NULL;
6 months ago
278
 if (stack_limit && stack_top < stack_limit){
279
 // current stack top is beyond limit - we are overrunning NOW
5 months ago
280
 return true;
6 months ago
281
 }
5 months ago
282
 Coroutine *me = g_c ? g_c->active : NULL;
6 months ago
283
 if (!me){
5 months ago
284
 return false;
6 months ago
285
 }
286
 if (me->guard){
5 months ago
287
 return !Check_Guard(me->guard);
6 months ago
288
 }
5 months ago
289
 return stack_top < me->limit;
6 months ago
290
 }
291
292
5 months ago
293
 static void ReserveStackSpace(
294
 Coroutines *cors,
6 months ago
295
 Coroutine *parent,
5 months ago
296
 size_t chunk_size,
297
 unsigned char *childs_limit
8 months ago
298
 ){
6 months ago
299
 unsigned char *chunk_of_stack = alloca(chunk_size);
300
 #if COROUTINE_RECORD_LOWEST_HEADROOM
301
 for (size_t i = 0; i <= chunk_size-GUARD_PATTERN_SIZE; i += GUARD_PATTERN_SIZE){
302
 Apply_Guard(&chunk_of_stack[i]);
303
 }
304
 #else
6 months ago
305
 Apply_Guard(chunk_of_stack);
6 months ago
306
 #endif
5 months ago
307
 if (parent){
308
 parent->guard = chunk_of_stack;
309
 parent->limit = chunk_of_stack;
310
 parent->base = chunk_of_stack + chunk_size;
311
 }
5 months ago
312
 stack_chunk_base(cors, parent, chunk_of_stack, childs_limit);
8 months ago
4
313
 }
314
8 months ago
315
316
 static void stack_chunk_base(
5 months ago
317
 Coroutines *cors,
5 months ago
318
 Coroutine *parent,
5 months ago
319
 unsigned char *prev_limit,
320
 unsigned char *limit
8 months ago
321
 ){
8 months ago
4
322
 Coroutine here;
5 months ago
323
 here.coroutines = cors;
6 months ago
324
 here.state = Coroutine_Free;
5 months ago
325
 here.prev_limit = prev_limit;
326
 here.size = 0;
327
 here.base = NULL;
328
 here.guard = limit;
329
 here.limit = limit;
330
 if (limit){
331
 here.base = (unsigned char *)&here - cors->gap_after;
332
 here.size = here.base - here.limit;
333
 Apply_Guard(limit);
334
 }
335
5 months ago
336
 // insert into all list
337
 if (parent){
338
 Link_AddAfter(&here.all_link, &parent->all_link);
339
 } else {
340
 List_AddHead(&cors->all, &here.all_link);
5 months ago
341
 }
5 months ago
342
 // add to free list
343
 List_AddTail(&cors->free, &here.link);
5 months ago
344
345
 cors->report.coroutines_pool_size += 1;
346
347
 if (!cors->tip || &here < cors->tip){
348
 cors->tip = &here;
349
 }
350
6 months ago
351
 for(;;){
352
 switch (setjmp(here.buf)) {
353
 case Chunk_Initial:
6 months ago
354
 if (here.state == Coroutine_Free){
6 months ago
355
 // return to the coroutine allocator
5 months ago
356
 longjmp(cors->chunk_allocated, 1);
6 months ago
357
 } else {
358
 assert(here.state == Coroutine_Complete);
359
 // we finish here to ensure the setjmp is redone
5 months ago
360
 if (cors->primary == &here) {
6 months ago
361
 // if primary coroutine - return to Coroutine_Run
5 months ago
362
 longjmp(cors->controller, Coroutines_CoroutineComplete);
6 months ago
363
 }
5 months ago
364
 _Cor_Mutex_Unlock(&cors->mutex);
6 months ago
365
 Coroutine_RunNext();
366
 assert(false);
367
 }
368
 case Chunk_Create:
6 months ago
369
 // Request to create a new chunk on the stack
370
 // We're here if the coroutine is:
371
 // Allocated, but not 'run' (Coroutine_Idle)
372
 // Run, but not not entered yet (Coroutine_Running)
373
 // Completed (Coroutine_Complete)
5 months ago
374
 // Free, and the coroutines system is starting - we're characterising the system
375
 assert(here.state == Coroutine_Idle ||
376
 here.state == Coroutine_Running ||
377
 here.state == Coroutine_Complete ||
378
 (here.state == Coroutine_Free && cors->state == Coroutines_Starting));
379
 ReserveStackSpace(here.coroutines, &here, here.size, NULL);
6 months ago
380
 assert(false);
5 months ago
381
 case Chunk_Split:
382
 // Request to split this free block into two
383
 // here.size will be set to our shorter size
384
 ReserveStackSpace(here.coroutines, &here, here.size, here.limit);
385
 assert(false);
6 months ago
386
 case Chunk_Enter:
387
 // request to start a coroutine (ie use the chunk for a coroutine)
388
 // arrive here with mutex locked
389
 assert(here.state == Coroutine_Running);
5 months ago
390
 here.coroutines->active = &here;
391
 _Cor_Mutex_Unlock(&cors->mutex);
6 months ago
392
 here.value = here.start(here.entry_param);
8 months ago
393
6 months ago
394
 // check the guard
395
 assert(Check_Guard(here.guard));
8 months ago
396
5 months ago
397
 _Cor_Mutex_Lock(&here.coroutines->mutex);
398
 here.coroutines->active = NULL;
6 months ago
399
 assert(here.state == Coroutine_Running);
5 months ago
400
 Link_Remove(&here.link);
6 months ago
401
 here.state = Coroutine_Complete;
5 months ago
402
 List_AddTail(&here.coroutines->inactive, &here.link);
6 months ago
403
 // Coroutine has completed
404
 // Loop round to redo the setjmp() - if this coroutine yielded, then the setjmp will
405
 // need reseting
8 months ago
4
406
 }
407
 }
408
 }
409
8 months ago
410
7 months ago
411
 static void Coroutine_RunNext(void)
8 months ago
412
 {
413
 // arrive here with mutex unlocked
5 months ago
414
 _Cor_Mutex_Lock(&g_c->waiting_mutex);
415
 _Cor_Mutex_Lock(&g_c->mutex);
416
 Coroutine *next = List_Link_Container(Coroutine, link, List_GetHead(&g_c->runable));
8 months ago
417
 assert(next->state == Coroutine_Running);
418
 longjmp(next->buf, Chunk_Enter);
419
 assert(false);
420
 }
421
422
7 months ago
423
 void Coroutine_StartSystem(void)
8 months ago
4
424
 {
5 months ago
425
 assert(!g_c);
8 months ago
426
5 months ago
427
 Coroutines *cors = _Cor_Malloc(sizeof(*g_c));
428
 assert(cors);
8 months ago
429
5 months ago
430
 cors->state = Coroutines_Starting;
431
 _Cor_Mutex_ctor(&cors->mutex);
8 months ago
432
5 months ago
433
 cors->tip = NULL;
434
 cors->active = NULL;
8 months ago
4
435
5 months ago
436
 List_Init(&cors->all);
5 months ago
437
 List_Init(&cors->free);
438
 List_Init(&cors->inactive);
439
 List_Init(&cors->runable);
440
 List_Init(&cors->waiting);
441
 _Cor_Mutex_ctor(&cors->waiting_mutex);
442
 _Cor_Mutex_Lock(&cors->waiting_mutex);
8 months ago
4
443
5 months ago
444
 cors->report.coroutines_created = 0;
445
 cors->report.coroutines_pool_size = 0;
446
 cors->report.largest_stack = 0;
447
448
 // Charactersize the system...
449
 if (!setjmp(cors->chunk_allocated)){
450
 ReserveStackSpace(cors, NULL, COROUTINE_STARTUP_STACK_SIZE, NULL);
8 months ago
4
451
 }
5 months ago
452
 Coroutine *cor = List_Link_Container(Coroutine, link, List_GetHead(&cors->free));
453
 cor->size = COROUTINE_STARTUP_STACK_SIZE;
454
 if (!setjmp(cors->chunk_allocated)){
455
 longjmp(cor->buf, Chunk_Create);
456
 }
457
 cors->gap_before = cor->prev_limit - (unsigned char *)cor;
458
 cors->gap_after = (unsigned char *)cor - cor->base;
459
 // ...charactersize the system
8 months ago
460
5 months ago
461
 // discard what we've just created
5 months ago
462
 List_Init(&cors->all);
5 months ago
463
 List_Init(&cors->free);
464
 cors->tip = NULL;
465
466
 cors->state = Coroutines_Started;
467
468
 g_c = cors;
8 months ago
4
469
 }
470
8 months ago
471
6 months ago
472
 void Coroutine_SetStackLimit(void *limit){
5 months ago
473
 assert(g_c);
5 months ago
474
 assert(!limit || !(g_c->state == Coroutines_Started || g_c->state == Coroutines_Active) || (unsigned char *)limit < (unsigned char *)g_c->tip || !g_c->tip);
5 months ago
475
 g_c->stack_limit = limit;
6 months ago
476
 }
477
478
7 months ago
479
 Coroutine_Report Coroutine_StopSystem(void)
8 months ago
4
480
 {
5 months ago
481
 assert(g_c);
482
 assert(g_c->state == Coroutines_Started);
483
 _Cor_Mutex_Lock(&g_c->mutex);
484
 g_c->state = Coroutines_Stopping;
8 months ago
4
485
5 months ago
486
 uintptr_t stackminheadroom;
6 months ago
487
 #if COROUTINE_RECORD_LOWEST_HEADROOM
5 months ago
488
 stackminheadroom = g_c->report.largest_stack;
489
 for (List_Link *link = g_c->free.fwd.link.next; Link_NextIsLink(link); link = Link_Next(link)){
8 months ago
490
 Coroutine *cor = List_Link_Container(Coroutine, link, link);
6 months ago
491
 if (cor->guard){
5 months ago
492
 for (uintptr_t i = 4; i < cor->size-3; i += 4){
6 months ago
493
 if (!Check_Guard(&cor->guard[i])){
494
 stackminheadroom = i < stackminheadroom ? i : stackminheadroom;
495
 break;
496
 }
8 months ago
497
 }
498
 }
499
 }
6 months ago
500
 #else
501
 stackminheadroom = 0;
502
 #endif
5 months ago
503
 g_c->report.lowest_headroom = stackminheadroom;
8 months ago
504
5 months ago
505
 assert(List_IsEmpty(&g_c->inactive));
506
 _Cor_Mutex_Unlock(&g_c->waiting_mutex);
507
 _Cor_Mutex_dtor(&g_c->waiting_mutex);
8 months ago
4
508
5 months ago
509
 assert(g_c->state == Coroutines_Stopping);
510
 _Cor_Mutex_Unlock(&g_c->mutex);
511
 _Cor_Mutex_dtor(&g_c->mutex);
8 months ago
512
5 months ago
513
 Coroutine_Report ret = g_c->report;
514
515
 _Cor_Free(g_c);
516
 g_c = NULL;
517
518
 return ret;
8 months ago
4
519
 }
520
8 months ago
521
8 months ago
522
 void Coroutine_Run_Coroutine(
523
 Coroutine *cor,
8 months ago
524
 void *value
525
 ){
526
 Coroutines *cors = cor->coroutines;
5 months ago
527
528
 // Can't Coroutine_Run_Coroutine() off-thread
529
 assert(g_c == cors);
530
7 months ago
531
 _Cor_Mutex_Lock(&cors->mutex);
8 months ago
532
 assert(cors->state == Coroutines_Started);
533
 cors->state = Coroutines_Active;
534
 cors->primary = cor;
8 months ago
535
7 months ago
536
 _Coroutine_Continue(cor, value, true);
8 months ago
4
537
8 months ago
538
 if (!setjmp(cors->controller)){
7 months ago
539
 _Cor_Mutex_Unlock(&cors->mutex);
8 months ago
540
8 months ago
4
541
 // start the first coroutine
542
 Coroutine_RunNext();
543
 }
8 months ago
544
 // arrive here with mutex locked
8 months ago
545
 assert(List_IsEmpty(&cors->runable));
546
 assert(List_IsEmpty(&cors->waiting));
547
 assert(cors->state == Coroutines_Active);
548
 cors->state = Coroutines_Started;
7 months ago
549
 _Cor_Mutex_Unlock(&cors->mutex);
8 months ago
550
 }
551
552
5 months ago
553
 bool Coroutine_Run(
5 months ago
554
 size_t stack,
8 months ago
555
 Coroutine_Start start,
5 months ago
556
 void *value,
557
 void **result
8 months ago
558
 ){
5 months ago
559
 if (g_c && g_c->active){
5 months ago
560
 void *res = start(value);
561
 if (result){
562
 *result = res;
563
 }
564
 // no failures, so...
565
 return false;
6 months ago
566
 }
5 months ago
567
 assert(!g_c || g_c->state == Coroutines_Started);
568
 bool need_start = !g_c;
6 months ago
569
 if (need_start){
570
 Coroutine_StartSystem();
571
 }
5 months ago
572
 Coroutine *cor = Coroutine_New(stack, start);
5 months ago
573
 if (!cor){
574
 // that didn't work
575
 return true;
576
 }
8 months ago
577
 Coroutine_Run_Coroutine(cor, value);
5 months ago
578
 if (result){
579
 *result = Coroutine_GetValue(cor);
580
 }
8 months ago
581
 Coroutine_Delete(cor);
6 months ago
582
 if (need_start){
583
 Coroutine_StopSystem();
584
 }
5 months ago
585
 // no failures, so...
586
 return false;
8 months ago
4
587
 }
588
589
5 months ago
590
 static void Coroutine_FreeToIdle(
591
 Coroutine *cor,
8 months ago
592
 Coroutine_Start start
593
 ){
5 months ago
594
 assert(cor->state == Coroutine_Free);
595
 cor->state = Coroutine_Idle;
596
 cor->start = start;
597
 cor->value = NULL;
598
 Link_Remove(&cor->link);
599
 List_AddHead(&g_c->inactive, &cor->link);
8 months ago
600
5 months ago
601
 g_c->report.coroutines_created += 1;
602
 }
603
604
605
 static void Coroutine_FreeToIdleSize(
606
 Coroutine *cor,
607
 Coroutine_Start start,
608
 size_t size
609
 ){
610
 assert(!cor->guard);
611
 cor->size = size;
612
 cor->base = (unsigned char *)cor - g_c->gap_after;
613
 cor->limit = cor->base - cor->size;
614
 Coroutine_FreeToIdle(cor, start);
615
 }
616
617
618
 static Coroutine *Coroutine_New_Lock_Assumed(
619
 size_t size,
620
 Coroutine_Start start
621
 ){
622
 List_Link *link;
623
624
 if (!g_c->tip){
625
 // no tip - time to create one
626
627
 // we're the non-Coroutine which starts the Coroutine system.
628
 // Add a single free block
629
 if (!setjmp(g_c->chunk_allocated)){
630
 ReserveStackSpace(g_c, NULL, COROUTINE_STARTUP_STACK_SIZE, NULL);
5 months ago
631
 }
5 months ago
632
 }
633
5 months ago
634
 Coroutine *cor = NULL;
5 months ago
635
 for (link = List_Begin(&g_c->free); Link_NextIsLink(link); link = Link_Next(link)){
5 months ago
636
 Coroutine *candidate = List_Link_Container(Coroutine, link, link);
637
 if (!candidate->guard) {
5 months ago
638
 // this must be the tip
5 months ago
639
 assert(candidate == g_c->tip);
5 months ago
640
641
 // If this is the only Coroutine in the system, go ahead and use it regardless of size.
642
 // Note: there can only be one free block if there's no other sort of blocks as we merge on free
643
 if (List_IsEmpty(&g_c->inactive) &&
644
 List_IsEmpty(&g_c->runable) &&
645
 List_IsEmpty(&g_c->waiting) ){
646
 if (g_c->stack_limit){
5 months ago
647
 size_t available = (unsigned char *)candidate - g_c->stack_limit - g_c->gap_after;
5 months ago
648
 size = available < size ? available : size;
649
 }
5 months ago
650
 Coroutine_FreeToIdleSize(candidate, start, size);
651
 return candidate;
6 months ago
652
 }
5 months ago
653
654
 // Not the only coroutine in the system - check size
655
 if (g_c->stack_limit){
656
 // there's a limit - see what that space allows....
5 months ago
657
 size_t available = (unsigned char *)candidate - g_c->stack_limit - g_c->gap_after;
5 months ago
658
659
 if (available < size){
660
 // not enough space for this coroutine
661
 return NULL;
662
 }
663
664
 if (available >= size + g_c->gap_before + g_c->gap_after + COROUTINE_MINIMUM_STACK_SIZE) {
665
 // not enough space for another coroutine - use all the space for this one
666
 size = available;
667
 }
6 months ago
668
 }
5 months ago
669
 Coroutine_FreeToIdleSize(candidate, start, size);
670
 return candidate;
8 months ago
4
671
 }
5 months ago
672
 if (candidate->size >= size && candidate > cor){
673
 // chunk big enough, and a better choice than cor
674
 cor = candidate;
675
 }
676
 }
677
678
 if (cor){
679
 // - work out whether we're splitting or using the whole chunk
680
 if (cor->size >= size + g_c->gap_before + g_c->gap_after + COROUTINE_MINIMUM_STACK_SIZE){
681
 // enough space for a second coroutine so split this free block
682
 cor->size = size;
683
 if (!setjmp(g_c->chunk_allocated)){
684
 longjmp(cor->buf, Chunk_Split);
5 months ago
685
 }
686
 }
5 months ago
687
 // cor now ready to use
688
 Coroutine_FreeToIdle(cor, start);
689
 return cor;
8 months ago
4
690
 }
691
5 months ago
692
 // No big-enough free blocks - check if there's space beyond the tip block
693
694
 if (g_c->stack_limit && g_c->stack_limit > (unsigned char *)g_c->tip->limit - sizeof(Coroutine) - size){
695
 // no space for a new stack block
696
 return NULL;
697
 }
698
 Coroutine *tip = g_c->tip;
699
 Coroutine *me = g_c->active;
700
 if (tip == me) {
701
 if (!setjmp(g_c->chunk_allocated)){
702
 ReserveStackSpace(g_c, me, StackTopNow() - me->limit, NULL);
703
 }
704
 } else {
705
 if (!setjmp(g_c->chunk_allocated)){
706
 longjmp(tip->buf, Chunk_Create);
707
 }
708
 }
709
5 months ago
710
 cor = List_Link_Container(Coroutine, link, List_GetTail(&g_c->free));
8 months ago
4
711
 assert(cor->state == Coroutine_Free);
5 months ago
712
 cor->size = size;
713
 cor->limit = (unsigned char *)cor - g_c->gap_after - size;
8 months ago
4
714
 cor->state = Coroutine_Idle;
715
 cor->start = start;
716
 cor->value = NULL;
5 months ago
717
 Link_Remove(&cor->link);
718
 List_AddHead(&g_c->inactive, &cor->link);
8 months ago
4
719
5 months ago
720
 g_c->report.coroutines_created += 1;
721
 return cor;
722
 }
8 months ago
723
5 months ago
724
725
 Coroutine *Coroutine_New(
726
 size_t stack,
727
 Coroutine_Start start
728
 ){
729
 assert(g_c);
730
 assert((g_c->state == Coroutines_Started && List_IsEmpty(&g_c->inactive)) || g_c->state == Coroutines_Active);
731
 assert(!Coroutine_StackHasOverrun());
732
733
 _Cor_Mutex_Lock(&g_c->mutex);
734
735
 Coroutine *cor = Coroutine_New_Lock_Assumed(stack, start);
736
737
 if (cor && cor->size > g_c->report.largest_stack){
738
 g_c->report.largest_stack = cor->size;
739
 }
740
741
 _Cor_Mutex_Unlock(&g_c->mutex);
742
8 months ago
4
743
 return cor;
744
 }
745
8 months ago
746
747
 void Coroutine_Delete(
748
 Coroutine *cor
749
 ){
5 months ago
750
 assert(!Coroutine_StackHasOverrun());
5 months ago
751
 if (cor){
752
 Coroutines *cors = cor->coroutines;
753
 _Cor_Mutex_Lock(&cors->mutex);
754
 assert(cor->state == Coroutine_Idle || cor->state == Coroutine_Complete);
755
 cor->state = Coroutine_Free;
5 months ago
756
 Link_Remove(&cor->link);
757
5 months ago
758
 // insert into free list
759
 List_AddHead(&cors->free, &cor->link);
5 months ago
760
761
 // Check for merge with following Coroutine
5 months ago
762
 List_Link *link = Link_Next(&cor->all_link);
5 months ago
763
 if (Link_NextIsLink(link)){
5 months ago
764
 Coroutine *listcor = List_Link_Container(Coroutine, all_link, link);
765
 if (listcor->state == Coroutine_Free){
5 months ago
766
 // merge
5 months ago
767
 cor->size += cor->limit - listcor->limit;
5 months ago
768
 cor->limit = listcor->limit;
769
 cor->guard = listcor->guard;
5 months ago
770
 Link_Remove(&listcor->all_link);
5 months ago
771
 Link_Remove(&listcor->link);
5 months ago
772
 if (g_c->tip == listcor){
773
 g_c->tip = cor;
774
 }
5 months ago
775
 }
776
 }
777
778
 // check for merge with prev coroutine
5 months ago
779
 link = Link_Prev(&cor->all_link);
5 months ago
780
 if (Link_PrevIsLink(link)){
5 months ago
781
 Coroutine *listcor = List_Link_Container(Coroutine, all_link, link);
782
 if (listcor->state == Coroutine_Free){
5 months ago
783
 // merge
5 months ago
784
 listcor->size += listcor->limit - cor->limit;
5 months ago
785
 listcor->limit = cor->limit;
786
 listcor->guard = cor->guard;
5 months ago
787
 Link_Remove(&cor->all_link);
5 months ago
788
 Link_Remove(&cor->link);
5 months ago
789
 if (g_c->tip == cor){
790
 g_c->tip = listcor;
791
 }
5 months ago
792
 }
793
 }
794
5 months ago
795
 _Cor_Mutex_Unlock(&cors->mutex);
796
 }
8 months ago
4
797
 }
798
8 months ago
799
7 months ago
800
 // Coroutine_Continue, assuming the mutex is claimed
801
 static void _Coroutine_Continue(
8 months ago
802
 Coroutine *cor,
803
 void *value,
804
 bool early
805
 ){
806
 Coroutines *cors = cor->coroutines;
8 months ago
4
807
 assert(cor->state == Coroutine_Idle || cor->state == Coroutine_Waiting);
808
 cor->entry_param = value;
809
 cor->state = Coroutine_Running;
5 months ago
810
 Link_Remove(&cor->link);
8 months ago
4
811
 if ( early ) {
8 months ago
812
 List_AddHead(&cors->runable, &cor->link);
8 months ago
4
813
 } else {
8 months ago
814
 List_AddTail(&cors->runable, &cor->link);
8 months ago
4
815
 }
7 months ago
816
 _Cor_Mutex_Unlock(&cors->waiting_mutex);
7 months ago
817
 }
818
819
820
 void Coroutine_Continue(
821
 Coroutine *cor,
822
 void *value,
823
 bool early
824
 ){
5 months ago
825
 assert(!Coroutine_StackHasOverrun());
7 months ago
826
 Coroutines *cors = cor->coroutines;
7 months ago
827
 _Cor_Mutex_Lock(&cors->mutex);
7 months ago
828
 _Coroutine_Continue(cor, value, early);
7 months ago
829
 _Cor_Mutex_Unlock(&cors->mutex);
8 months ago
4
830
 }
831
8 months ago
832
833
 void *Coroutine_Yield(
834
 void *value,
835
 Coroutine_YieldCallback on_yield,
8 months ago
836
 void *yield_me
8 months ago
837
 ){
5 months ago
838
 assert(g_c);
839
 Coroutine *me = g_c->active;
6 months ago
840
 assert(me);
5 months ago
841
 assert(!Coroutine_StackHasOverrun());
8 months ago
842
5 months ago
843
 _Cor_Mutex_Lock(&g_c->mutex);
8 months ago
844
 Coroutines *cors = me->coroutines;
5 months ago
845
 assert(me && me->state == Coroutine_Running && cors == g_c);
6 months ago
846
 me->stack_top = StackTopNow();
8 months ago
4
847
 me->value = value;
848
 me->state = Coroutine_Waiting;
8 months ago
849
5 months ago
850
 Link_Remove(&me->link);
7 months ago
851
 if (!List_IsEmpty(&cors->runable)){
7 months ago
852
 _Cor_Mutex_Unlock(&cors->waiting_mutex);
7 months ago
853
 }
8 months ago
854
 List_AddTail(&cors->waiting, &me->link);
8 months ago
855
8 months ago
856
 switch (setjmp(me->buf)){
857
 case Chunk_Initial:
7 months ago
858
 _Cor_Mutex_Unlock(&cors->mutex);
8 months ago
859
 on_yield(yield_me);
8 months ago
4
860
 Coroutine_RunNext();
6 months ago
861
 assert(false);
8 months ago
862
 case Chunk_Create:
5 months ago
863
 assert(me == g_c->tip);
864
 ReserveStackSpace(me->coroutines, me, me->stack_top - me->limit, NULL);
8 months ago
865
 assert(false);
866
 case Chunk_Enter:
867
 // arrive here with mutex locked
8 months ago
868
 cors->active = me;
5 months ago
869
 assert(!Coroutine_StackHasOverrun());
8 months ago
870
 // when we return here - we are running again
871
 assert(me->state == Coroutine_Running);
872
 void *res = me->entry_param;
7 months ago
873
 _Cor_Mutex_Unlock(&cors->mutex);
8 months ago
874
 return res;
8 months ago
4
875
 }
8 months ago
876
 return NULL;
8 months ago
4
877
 }
878
8 months ago
879
880
 void *Coroutine_GetValue(
881
 Coroutine *cor
882
 ){
8 months ago
4
883
 return cor->value;
884
 }
885
8 months ago
886
7 months ago
887
 Coroutine *Coroutine_GetActive(void)
8 months ago
4
888
 {
5 months ago
889
 return g_c ? g_c->active : NULL;
8 months ago
4
890
 }
891
8 months ago
892
7 months ago
893
 intptr_t Coroutine_GetStackHeadroom(void){
5 months ago
894
 assert(g_c);
895
 assert(!Coroutine_StackHasOverrun());
896
 Coroutine *me = g_c->active;
6 months ago
897
 if (!me){
898
 // no active coroutine
5 months ago
899
 unsigned char *stack_limit = g_c->stack_limit;
6 months ago
900
 if (stack_limit){
901
 // no stack limit - assume we'll use COROUTINE_STACK_SIZE
902
 return StackTopNow() - stack_limit;
903
 } else {
904
 // no information where the stack ends - return something
5 months ago
905
 return COROUTINE_MINIMUM_STACK_SIZE;
6 months ago
906
 }
907
 }
5 months ago
908
 return StackTopNow() - me->limit;
8 months ago
909
 }
910
911
6 months ago
912
 // This is used to avoid compiler warnings about returning the address of a local
913
 static inline void *StopAddressWarnings(void *p)
914
 {
915
 return p;
8 months ago
916
 }
917
918
6 months ago
919
 void *Coroutine_GetStackHWM(void){
5 months ago
920
 assert(g_c);
921
 assert(g_c->state == Coroutines_Active);
922
 assert(!Coroutine_StackHasOverrun());
6 months ago
923
 // Find where the guards end
924
 unsigned char *guard;
5 months ago
925
 for (guard = g_c->active->guard; Check_Guard(guard); guard += 4){
6 months ago
926
 // do nothing
927
 }
928
 return guard;
929
 }
7 months ago
930
931
6 months ago
932
 void Coroutine_ClearStackForHWM(void){
5 months ago
933
 assert(g_c);
934
 assert(g_c->state == Coroutines_Active);
935
 assert(!Coroutine_StackHasOverrun());
6 months ago
936
 unsigned char *end = StackTopNow() - GUARD_PATTERN_SIZE;
5 months ago
937
 for (unsigned char *guard = g_c->active->guard+GUARD_PATTERN_SIZE; guard <= end; guard += GUARD_PATTERN_SIZE){
6 months ago
938
 Apply_Guard(guard);
6 months ago
939
 }
940
 }
941
942
5 months ago
943
 static bool Coroutine_CanStartCoroutine_Lock_Assumed(
944
 size_t size
945
 ){
946
 assert(g_c);
947
 assert(g_c->state == Coroutines_Started || g_c->state == Coroutines_Active);
948
 assert(!Coroutine_StackHasOverrun());
949
950
 if (!g_c->stack_limit){
6 months ago
951
 return true;
952
 }
6 months ago
953
5 months ago
954
 if (!g_c->tip){
955
 return true;
956
 }
957
958
 if (g_c->tip->state == Coroutine_Free){
959
 // last block is free
960
 if ((unsigned char *)g_c->tip - g_c->stack_limit >= (ptrdiff_t)(g_c->gap_after + size)){
961
 // enough room in free block, which is the last block
962
 return true;
963
 }
964
 } else {
965
 // last block is allocated
966
 if (g_c->tip->limit - g_c->stack_limit >= (ptrdiff_t)(g_c->gap_before + g_c->gap_after + size)){
967
 // enough room after the last block, which is allocated
968
 return true;
969
 }
970
 }
971
972
 // not enough room between allocated blocks and stack limit, so check free list
973
 List_Link *link;
974
 for (link = List_Begin(&g_c->free); Link_NextIsLink(link); link = Link_Next(link)){
975
 Coroutine *cor = List_Link_Container(Coroutine, link, link);
976
 if (cor->size >= size){
977
 return true;
978
 }
979
 }
980
981
 return false;
6 months ago
982
 }
983
984
5 months ago
985
 bool Coroutine_CanStartCoroutine(
986
 size_t size
987
 ){
988
 _Cor_Mutex_Lock(&g_c->mutex);
989
990
 bool result = Coroutine_CanStartCoroutine_Lock_Assumed(size);
991
992
 _Cor_Mutex_Unlock(&g_c->mutex);
993
994
 return result;
995
 }
996
7 months ago
997
 void *Coroutine_GetCStackTop(void){
5 months ago
998
 assert(!Coroutine_StackHasOverrun());
999
 if ((g_c->state == Coroutines_Started || g_c->state == Coroutines_Active) && g_c->tip != g_c->active) {
1000
 return g_c->tip->stack_top;
6 months ago
1001
 } else {
1002
 return StackTopNow();
1003
 }
8 months ago
1004
 }
1005
1006
6 months ago
1007
 static unsigned char *StackTopNow(void){
6 months ago
1008
 unsigned char here[4];
1009
 return StopAddressWarnings(here);
1010
 }
1011
1012
8 months ago
1013
 struct Coroutine_ChainParam {
1014
 Coroutine_Start start;
1015
 void *value;
1016
 Coroutine *ret;
1017
 };
1018
1019
1020
 static void *Coroutine_ChainFn(
1021
 void *param
1022
 ){
1023
 struct Coroutine_ChainParam *params = (struct Coroutine_ChainParam *)param;
1024
 Coroutine_Continue(params->ret, params->start(params->value), true);
1025
 return NULL;
1026
 }
1027
1028
1029
 static void Coroutine_ChainYield(
1030
 void *unused
1031
 ){
1032
 (void)unused;
1033
 }
1034
1035
5 months ago
1036
 bool Coroutine_Chain(
5 months ago
1037
 size_t size,
8 months ago
1038
 Coroutine_Start start,
5 months ago
1039
 void *value,
1040
 void **result
8 months ago
1041
 ){
7 months ago
1042
 assert(Check_Guard(Coroutine_GetActive()->guard));
5 months ago
1043
 Coroutine *cor = Coroutine_New(size, Coroutine_ChainFn);
5 months ago
1044
 if (!cor){
1045
 // failed
1046
 return true;
1047
 }
8 months ago
1048
 struct Coroutine_ChainParam params = {
1049
 start,
1050
 value,
1051
 Coroutine_GetActive()
1052
 };
1053
 Coroutine_Continue(cor, &params, true);
1054
 void *res = Coroutine_Yield(NULL, Coroutine_ChainYield, NULL);
1055
 Coroutine_Delete(cor);
5 months ago
1056
 if (result){
1057
 *result = res;
1058
 }
1059
 // success!
1060
 return false;
8 months ago
1061
 }
1062
1063
8 months ago
1064
 bool Coroutine_IsRunning(
1065
 Coroutine *cor
1066
 )
8 months ago
4
1067
 {
8 months ago
1068
 int state = cor->state;
1069
 return state == Coroutine_Running || state == Coroutine_Waiting;
8 months ago
4
1070
 }
8 months ago
1071
1072
6 months ago
1073
 bool Coroutine_IsComplete(
1074
 Coroutine *cor
1075
 )
1076
 {
1077
 int state = cor->state;
1078
 return state == Coroutine_Complete;
1079
 }
1080
1081
7 months ago
1082
 bool Coroutine_IsStarted(void){
5 months ago
1083
 return g_c && (g_c->state == Coroutines_Active || g_c->state == Coroutines_Started);
8 months ago
1084
 }
5 months ago
1085
1086
 void _Coroutine_Dump(void){
1087
 char *state_to_text[] = {
1088
 "Free",
1089
 "Idle",
1090
 "Running",
1091
 "Waiting",
1092
 "Complete"
1093
 };
1094
 unsigned idx = 0;
1095
 List_Link *link;
1096
 for (link = List_Begin(&g_c->all); Link_NextIsLink(link); link = Link_Next(link)){
1097
 Coroutine *cor = List_Link_Container(Coroutine, all_link, link);
1098
 printf("%d) %p (%s) %ld%s\n", idx++, cor, state_to_text[cor->state], cor->size, cor == g_c->tip ? " (TIP)" : "");
1099
 }
1100
 }
1101