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1 jermar 1
/*
2
 * Copyright (C) 2001-2004 Jakub Jermar
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
1757 jermar 29
/** @addtogroup genericproc
1702 cejka 30
 * @{
31
 */
32
 
1248 jermar 33
/**
1702 cejka 34
 * @file
1248 jermar 35
 * @brief   Thread management functions.
36
 */
37
 
1 jermar 38
#include <proc/scheduler.h>
39
#include <proc/thread.h>
40
#include <proc/task.h>
1078 jermar 41
#include <proc/uarg.h>
1 jermar 42
#include <mm/frame.h>
43
#include <mm/page.h>
44
#include <arch/asm.h>
45
#include <arch.h>
46
#include <synch/synch.h>
47
#include <synch/spinlock.h>
48
#include <synch/waitq.h>
49
#include <synch/rwlock.h>
50
#include <cpu.h>
51
#include <func.h>
52
#include <context.h>
1158 jermar 53
#include <adt/btree.h>
788 jermar 54
#include <adt/list.h>
1 jermar 55
#include <typedefs.h>
56
#include <time/clock.h>
7 jermar 57
#include <config.h>
58
#include <arch/interrupt.h>
10 jermar 59
#include <smp/ipi.h>
76 jermar 60
#include <arch/faddr.h>
1104 jermar 61
#include <atomic.h>
195 vana 62
#include <memstr.h>
777 palkovsky 63
#include <print.h>
787 palkovsky 64
#include <mm/slab.h>
65
#include <debug.h>
1066 jermar 66
#include <main/uinit.h>
1288 jermar 67
#include <syscall/copy.h>
68
#include <errno.h>
7 jermar 69
 
1 jermar 70
 
1571 jermar 71
/** Thread states */
72
char *thread_states[] = {
73
    "Invalid",
74
    "Running",
75
    "Sleeping",
76
    "Ready",
77
    "Entering",
78
    "Exiting",
79
    "Undead"
80
};
81
 
1636 jermar 82
/** Lock protecting the threads_btree B+tree. For locking rules, see declaration thereof. */
1158 jermar 83
SPINLOCK_INITIALIZE(threads_lock);
1 jermar 84
 
1636 jermar 85
/** B+tree of all threads.
86
 *
87
 * When a thread is found in the threads_btree B+tree, it is guaranteed to exist as long
88
 * as the threads_lock is held.
89
 */
90
btree_t threads_btree;     
91
 
623 jermar 92
SPINLOCK_INITIALIZE(tidlock);
1780 jermar 93
uint32_t last_tid = 0;
1 jermar 94
 
787 palkovsky 95
static slab_cache_t *thread_slab;
906 palkovsky 96
#ifdef ARCH_HAS_FPU
97
slab_cache_t *fpu_context_slab;
98
#endif
107 decky 99
 
100
/** Thread wrapper
101
 *
102
 * This wrapper is provided to ensure that every thread
1 jermar 103
 * makes a call to thread_exit() when its implementing
104
 * function returns.
105
 *
413 jermar 106
 * interrupts_disable() is assumed.
107 decky 107
 *
1 jermar 108
 */
452 decky 109
static void cushion(void)
1 jermar 110
{
15 jermar 111
    void (*f)(void *) = THREAD->thread_code;
112
    void *arg = THREAD->thread_arg;
1 jermar 113
 
213 jermar 114
    /* this is where each thread wakes up after its creation */
15 jermar 115
    spinlock_unlock(&THREAD->lock);
413 jermar 116
    interrupts_enable();
1 jermar 117
 
118
    f(arg);
119
    thread_exit();
120
    /* not reached */
121
}
122
 
787 palkovsky 123
/** Initialization and allocation for thread_t structure */
124
static int thr_constructor(void *obj, int kmflags)
125
{
1820 decky 126
    thread_t *t = (thread_t *) obj;
107 decky 127
 
787 palkovsky 128
    spinlock_initialize(&t->lock, "thread_t_lock");
129
    link_initialize(&t->rq_link);
130
    link_initialize(&t->wq_link);
131
    link_initialize(&t->th_link);
1854 jermar 132
 
133
    /* call the architecture-specific part of the constructor */
134
    thr_constructor_arch(t);
787 palkovsky 135
 
906 palkovsky 136
#ifdef ARCH_HAS_FPU
137
#  ifdef CONFIG_FPU_LAZY
138
    t->saved_fpu_context = NULL;
139
#  else
140
    t->saved_fpu_context = slab_alloc(fpu_context_slab,kmflags);
141
    if (!t->saved_fpu_context)
142
        return -1;
143
#  endif
144
#endif  
145
 
1766 palkovsky 146
    t->kstack = frame_alloc(STACK_FRAMES, FRAME_KA | kmflags);
147
    if (! t->kstack) {
906 palkovsky 148
#ifdef ARCH_HAS_FPU
149
        if (t->saved_fpu_context)
150
            slab_free(fpu_context_slab,t->saved_fpu_context);
151
#endif
842 palkovsky 152
        return -1;
906 palkovsky 153
    }
787 palkovsky 154
 
155
    return 0;
156
}
157
 
158
/** Destruction of thread_t object */
159
static int thr_destructor(void *obj)
160
{
1820 decky 161
    thread_t *t = (thread_t *) obj;
787 palkovsky 162
 
1854 jermar 163
    /* call the architecture-specific part of the destructor */
164
    thr_destructor_arch(t);
165
 
1760 palkovsky 166
    frame_free(KA2PA(t->kstack));
906 palkovsky 167
#ifdef ARCH_HAS_FPU
168
    if (t->saved_fpu_context)
169
        slab_free(fpu_context_slab,t->saved_fpu_context);
170
#endif
787 palkovsky 171
    return 1; /* One page freed */
172
}
173
 
107 decky 174
/** Initialize threads
175
 *
176
 * Initialize kernel threads support.
177
 *
178
 */
1 jermar 179
void thread_init(void)
180
{
15 jermar 181
    THREAD = NULL;
625 palkovsky 182
    atomic_set(&nrdy,0);
787 palkovsky 183
    thread_slab = slab_cache_create("thread_slab",
184
                    sizeof(thread_t),0,
185
                    thr_constructor, thr_destructor, 0);
906 palkovsky 186
#ifdef ARCH_HAS_FPU
187
    fpu_context_slab = slab_cache_create("fpu_slab",
188
                         sizeof(fpu_context_t),
189
                         FPU_CONTEXT_ALIGN,
190
                         NULL, NULL, 0);
191
#endif
1158 jermar 192
 
193
    btree_create(&threads_btree);
1 jermar 194
}
195
 
107 decky 196
/** Make thread ready
197
 *
198
 * Switch thread t to the ready state.
199
 *
200
 * @param t Thread to make ready.
201
 *
202
 */
1 jermar 203
void thread_ready(thread_t *t)
204
{
205
    cpu_t *cpu;
206
    runq_t *r;
413 jermar 207
    ipl_t ipl;
625 palkovsky 208
    int i, avg;
1 jermar 209
 
413 jermar 210
    ipl = interrupts_disable();
1 jermar 211
 
212
    spinlock_lock(&t->lock);
213
 
1086 palkovsky 214
    ASSERT(! (t->state == Ready));
215
 
413 jermar 216
    i = (t->priority < RQ_COUNT -1) ? ++t->priority : t->priority;
1 jermar 217
 
16 jermar 218
    cpu = CPU;
1854 jermar 219
    if (t->flags & THREAD_FLAG_WIRED) {
1 jermar 220
        cpu = t->cpu;
221
    }
1083 palkovsky 222
    t->state = Ready;
1 jermar 223
    spinlock_unlock(&t->lock);
224
 
107 decky 225
    /*
1 jermar 226
     * Append t to respective ready queue on respective processor.
227
     */
228
    r = &cpu->rq[i];
229
    spinlock_lock(&r->lock);
230
    list_append(&t->rq_link, &r->rq_head);
231
    r->n++;
232
    spinlock_unlock(&r->lock);
233
 
475 jermar 234
    atomic_inc(&nrdy);
625 palkovsky 235
    avg = atomic_get(&nrdy) / config.cpu_active;
783 palkovsky 236
    atomic_inc(&cpu->nrdy);
1 jermar 237
 
413 jermar 238
    interrupts_restore(ipl);
1 jermar 239
}
240
 
787 palkovsky 241
/** Destroy thread memory structure
242
 *
243
 * Detach thread from all queues, cpus etc. and destroy it.
244
 *
245
 * Assume thread->lock is held!!
246
 */
247
void thread_destroy(thread_t *t)
248
{
1579 jermar 249
    bool destroy_task = false; 
250
 
1581 jermar 251
    ASSERT(t->state == Exiting || t->state == Undead);
787 palkovsky 252
    ASSERT(t->task);
253
    ASSERT(t->cpu);
254
 
255
    spinlock_lock(&t->cpu->lock);
256
    if(t->cpu->fpu_owner==t)
257
        t->cpu->fpu_owner=NULL;
258
    spinlock_unlock(&t->cpu->lock);
259
 
1579 jermar 260
    spinlock_unlock(&t->lock);
261
 
262
    spinlock_lock(&threads_lock);
1780 jermar 263
    btree_remove(&threads_btree, (btree_key_t) ((uintptr_t ) t), NULL);
1579 jermar 264
    spinlock_unlock(&threads_lock);
265
 
787 palkovsky 266
    /*
267
     * Detach from the containing task.
268
     */
269
    spinlock_lock(&t->task->lock);
270
    list_remove(&t->th_link);
1579 jermar 271
    if (--t->task->refcount == 0) {
272
        t->task->accept_new_threads = false;
273
        destroy_task = true;
274
    }
275
    spinlock_unlock(&t->task->lock);   
787 palkovsky 276
 
1579 jermar 277
    if (destroy_task)
278
        task_destroy(t->task);
787 palkovsky 279
 
280
    slab_free(thread_slab, t);
281
}
282
 
107 decky 283
/** Create new thread
284
 *
285
 * Create a new thread.
286
 *
287
 * @param func  Thread's implementing function.
288
 * @param arg   Thread's implementing function argument.
289
 * @param task  Task to which the thread belongs.
290
 * @param flags Thread flags.
1062 jermar 291
 * @param name  Symbolic name.
107 decky 292
 *
293
 * @return New thread's structure on success, NULL on failure.
294
 *
295
 */
1062 jermar 296
thread_t *thread_create(void (* func)(void *), void *arg, task_t *task, int flags, char *name)
1 jermar 297
{
298
    thread_t *t;
822 palkovsky 299
    ipl_t ipl;
300
 
787 palkovsky 301
    t = (thread_t *) slab_alloc(thread_slab, 0);
842 palkovsky 302
    if (!t)
303
        return NULL;
1 jermar 304
 
822 palkovsky 305
    /* Not needed, but good for debugging */
1820 decky 306
    memsetb((uintptr_t) t->kstack, THREAD_STACK_SIZE * 1 << STACK_FRAMES, 0);
822 palkovsky 307
 
308
    ipl = interrupts_disable();
309
    spinlock_lock(&tidlock);
310
    t->tid = ++last_tid;
311
    spinlock_unlock(&tidlock);
312
    interrupts_restore(ipl);
313
 
314
    context_save(&t->saved_context);
1780 jermar 315
    context_set(&t->saved_context, FADDR(cushion), (uintptr_t) t->kstack, THREAD_STACK_SIZE);
822 palkovsky 316
 
317
    the_initialize((the_t *) t->kstack);
318
 
319
    ipl = interrupts_disable();
320
    t->saved_context.ipl = interrupts_read();
321
    interrupts_restore(ipl);
322
 
1066 jermar 323
    memcpy(t->name, name, THREAD_NAME_BUFLEN);
324
 
822 palkovsky 325
    t->thread_code = func;
326
    t->thread_arg = arg;
327
    t->ticks = -1;
328
    t->priority = -1;       /* start in rq[0] */
329
    t->cpu = NULL;
1854 jermar 330
    t->flags = flags;
822 palkovsky 331
    t->state = Entering;
332
    t->call_me = NULL;
333
    t->call_me_with = NULL;
334
 
335
    timeout_initialize(&t->sleep_timeout);
1502 jermar 336
    t->sleep_interruptible = false;
822 palkovsky 337
    t->sleep_queue = NULL;
338
    t->timeout_pending = 0;
1288 jermar 339
 
340
    t->in_copy_from_uspace = false;
341
    t->in_copy_to_uspace = false;
1579 jermar 342
 
343
    t->interrupted = false;
1661 jermar 344
    t->join_type = None;
1571 jermar 345
    t->detached = false;
346
    waitq_initialize(&t->join_wq);
347
 
822 palkovsky 348
    t->rwlock_holder_type = RWLOCK_NONE;
210 decky 349
 
822 palkovsky 350
    t->task = task;
351
 
860 decky 352
    t->fpu_context_exists = 0;
353
    t->fpu_context_engaged = 0;
1854 jermar 354
 
355
    thread_create_arch(t);      /* might depend on previous initialization */
822 palkovsky 356
 
357
    /*
1579 jermar 358
     * Attach to the containing task.
359
     */
1687 jermar 360
    ipl = interrupts_disable();  
1579 jermar 361
    spinlock_lock(&task->lock);
362
    if (!task->accept_new_threads) {
363
        spinlock_unlock(&task->lock);
364
        slab_free(thread_slab, t);
1687 jermar 365
        interrupts_restore(ipl);
1579 jermar 366
        return NULL;
367
    }
368
    list_append(&t->th_link, &task->th_head);
1585 jermar 369
    if (task->refcount++ == 0)
370
        task->main_thread = t;
1579 jermar 371
    spinlock_unlock(&task->lock);
372
 
373
    /*
822 palkovsky 374
     * Register this thread in the system-wide list.
375
     */
376
    spinlock_lock(&threads_lock);
1780 jermar 377
    btree_insert(&threads_btree, (btree_key_t) ((uintptr_t) t), (void *) t, NULL);
822 palkovsky 378
    spinlock_unlock(&threads_lock);
379
 
380
    interrupts_restore(ipl);
860 decky 381
 
1 jermar 382
    return t;
383
}
384
 
1687 jermar 385
/** Terminate thread.
107 decky 386
 *
387
 * End current thread execution and switch it to the exiting
388
 * state. All pending timeouts are executed.
389
 *
390
 */
1 jermar 391
void thread_exit(void)
392
{
413 jermar 393
    ipl_t ipl;
1 jermar 394
 
395
restart:
413 jermar 396
    ipl = interrupts_disable();
15 jermar 397
    spinlock_lock(&THREAD->lock);
398
    if (THREAD->timeout_pending) { /* busy waiting for timeouts in progress */
399
        spinlock_unlock(&THREAD->lock);
413 jermar 400
        interrupts_restore(ipl);
1 jermar 401
        goto restart;
402
    }
15 jermar 403
    THREAD->state = Exiting;
404
    spinlock_unlock(&THREAD->lock);
1 jermar 405
    scheduler();
1595 palkovsky 406
 
407
    /* Not reached */
408
    while (1)
409
        ;
1 jermar 410
}
411
 
107 decky 412
 
413
/** Thread sleep
414
 *
415
 * Suspend execution of the current thread.
416
 *
417
 * @param sec Number of seconds to sleep.
418
 *
419
 */
1780 jermar 420
void thread_sleep(uint32_t sec)
1 jermar 421
{
125 jermar 422
    thread_usleep(sec*1000000);
1 jermar 423
}
107 decky 424
 
1571 jermar 425
/** Wait for another thread to exit.
426
 *
427
 * @param t Thread to join on exit.
428
 * @param usec Timeout in microseconds.
429
 * @param flags Mode of operation.
430
 *
431
 * @return An error code from errno.h or an error code from synch.h.
432
 */
1780 jermar 433
int thread_join_timeout(thread_t *t, uint32_t usec, int flags)
1571 jermar 434
{
435
    ipl_t ipl;
436
    int rc;
437
 
438
    if (t == THREAD)
439
        return EINVAL;
440
 
441
    /*
442
     * Since thread join can only be called once on an undetached thread,
443
     * the thread pointer is guaranteed to be still valid.
444
     */
445
 
446
    ipl = interrupts_disable();
447
    spinlock_lock(&t->lock);
448
    ASSERT(!t->detached);
449
    spinlock_unlock(&t->lock);
1687 jermar 450
    interrupts_restore(ipl);
1571 jermar 451
 
1687 jermar 452
    rc = waitq_sleep_timeout(&t->join_wq, usec, flags);
1571 jermar 453
 
454
    return rc; 
455
}
456
 
457
/** Detach thread.
458
 *
459
 * Mark the thread as detached, if the thread is already in the Undead state,
460
 * deallocate its resources.
461
 *
462
 * @param t Thread to be detached.
463
 */
464
void thread_detach(thread_t *t)
465
{
466
    ipl_t ipl;
467
 
468
    /*
469
     * Since the thread is expected to not be already detached,
470
     * pointer to it must be still valid.
471
     */
472
    ipl = interrupts_disable();
473
    spinlock_lock(&t->lock);
474
    ASSERT(!t->detached);
475
    if (t->state == Undead) {
476
        thread_destroy(t);  /* unlocks &t->lock */
477
        interrupts_restore(ipl);
478
        return;
479
    } else {
480
        t->detached = true;
481
    }
482
    spinlock_unlock(&t->lock);
483
    interrupts_restore(ipl);
484
}
485
 
107 decky 486
/** Thread usleep
487
 *
488
 * Suspend execution of the current thread.
489
 *
490
 * @param usec Number of microseconds to sleep.
491
 *
492
 */
1780 jermar 493
void thread_usleep(uint32_t usec)
1 jermar 494
{
495
    waitq_t wq;
496
 
497
    waitq_initialize(&wq);
498
 
1502 jermar 499
    (void) waitq_sleep_timeout(&wq, usec, SYNCH_FLAGS_NON_BLOCKING);
1 jermar 500
}
501
 
107 decky 502
/** Register thread out-of-context invocation
503
 *
504
 * Register a function and its argument to be executed
505
 * on next context switch to the current thread.
506
 *
507
 * @param call_me      Out-of-context function.
508
 * @param call_me_with Out-of-context function argument.
509
 *
510
 */
1 jermar 511
void thread_register_call_me(void (* call_me)(void *), void *call_me_with)
512
{
413 jermar 513
    ipl_t ipl;
1 jermar 514
 
413 jermar 515
    ipl = interrupts_disable();
15 jermar 516
    spinlock_lock(&THREAD->lock);
517
    THREAD->call_me = call_me;
518
    THREAD->call_me_with = call_me_with;
519
    spinlock_unlock(&THREAD->lock);
413 jermar 520
    interrupts_restore(ipl);
1 jermar 521
}
777 palkovsky 522
 
523
/** Print list of threads debug info */
524
void thread_print_list(void)
525
{
526
    link_t *cur;
527
    ipl_t ipl;
528
 
529
    /* Messing with thread structures, avoid deadlock */
530
    ipl = interrupts_disable();
531
    spinlock_lock(&threads_lock);
532
 
1158 jermar 533
    for (cur = threads_btree.leaf_head.next; cur != &threads_btree.leaf_head; cur = cur->next) {
534
        btree_node_t *node;
535
        int i;
536
 
537
        node = list_get_instance(cur, btree_node_t, leaf_link);
538
        for (i = 0; i < node->keys; i++) {
539
            thread_t *t;
540
 
541
            t = (thread_t *) node->value[i];
1839 decky 542
            printf("%s: address=%#zx, tid=%zd, state=%s, task=%#zx, context=%ld, code=%#zx, stack=%#zx, cpu=",
543
                t->name, t, t->tid, thread_states[t->state], t->task, t->task->context, t->thread_code, t->kstack);
1158 jermar 544
            if (t->cpu)
1458 palkovsky 545
                printf("cpu%zd", t->cpu->id);
1158 jermar 546
            else
547
                printf("none");
1458 palkovsky 548
            if (t->state == Sleeping) {
1735 decky 549
                printf(", kst=%#zx", t->kstack);
550
                printf(", wq=%#zx", t->sleep_queue);
1458 palkovsky 551
            }
1158 jermar 552
            printf("\n");
553
        }
777 palkovsky 554
    }
555
 
556
    spinlock_unlock(&threads_lock);
1060 palkovsky 557
    interrupts_restore(ipl);
777 palkovsky 558
}
1066 jermar 559
 
1158 jermar 560
/** Check whether thread exists.
561
 *
562
 * Note that threads_lock must be already held and
563
 * interrupts must be already disabled.
564
 *
565
 * @param t Pointer to thread.
566
 *
567
 * @return True if thread t is known to the system, false otherwise.
568
 */
569
bool thread_exists(thread_t *t)
570
{
571
    btree_node_t *leaf;
572
 
1780 jermar 573
    return btree_search(&threads_btree, (btree_key_t) ((uintptr_t) t), &leaf) != NULL;
1158 jermar 574
}
575
 
1066 jermar 576
/** Process syscall to create new thread.
577
 *
578
 */
1780 jermar 579
unative_t sys_thread_create(uspace_arg_t *uspace_uarg, char *uspace_name)
1066 jermar 580
{
1210 vana 581
    thread_t *t;
582
    char namebuf[THREAD_NAME_BUFLEN];
1103 jermar 583
    uspace_arg_t *kernel_uarg;
1780 jermar 584
    uint32_t tid;
1288 jermar 585
    int rc;
1066 jermar 586
 
1288 jermar 587
    rc = copy_from_uspace(namebuf, uspace_name, THREAD_NAME_BUFLEN);
588
    if (rc != 0)
1780 jermar 589
        return (unative_t) rc;
1066 jermar 590
 
1078 jermar 591
    kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0);
1288 jermar 592
    rc = copy_from_uspace(kernel_uarg, uspace_uarg, sizeof(uspace_arg_t));
593
    if (rc != 0) {
594
        free(kernel_uarg);
1780 jermar 595
        return (unative_t) rc;
1288 jermar 596
    }
1078 jermar 597
 
1854 jermar 598
    if ((t = thread_create(uinit, kernel_uarg, TASK, THREAD_FLAG_USPACE, namebuf))) {
1066 jermar 599
        tid = t->tid;
1210 vana 600
        thread_ready(t);
1780 jermar 601
        return (unative_t) tid;
1210 vana 602
    } else {
1078 jermar 603
        free(kernel_uarg);
1210 vana 604
    }
1066 jermar 605
 
1780 jermar 606
    return (unative_t) ENOMEM;
1066 jermar 607
}
608
 
609
/** Process syscall to terminate thread.
610
 *
611
 */
1780 jermar 612
unative_t sys_thread_exit(int uspace_status)
1066 jermar 613
{
1210 vana 614
    thread_exit();
615
    /* Unreachable */
616
    return 0;
1066 jermar 617
}
1702 cejka 618
 
1757 jermar 619
/** @}
1702 cejka 620
 */