Subversion Repositories HelenOS

Rev

Rev 2118 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1 jermar 1
/*
2071 jermar 2
 * Copyright (c) 2001-2004 Jakub Jermar
1 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   Task management.
36
 */
37
 
973 palkovsky 38
#include <main/uinit.h>
1 jermar 39
#include <proc/thread.h>
40
#include <proc/task.h>
1078 jermar 41
#include <proc/uarg.h>
703 jermar 42
#include <mm/as.h>
814 palkovsky 43
#include <mm/slab.h>
1 jermar 44
#include <synch/spinlock.h>
2109 jermar 45
#include <synch/waitq.h>
1 jermar 46
#include <arch.h>
47
#include <panic.h>
1159 jermar 48
#include <adt/btree.h>
788 jermar 49
#include <adt/list.h>
955 palkovsky 50
#include <ipc/ipc.h>
1174 jermar 51
#include <security/cap.h>
955 palkovsky 52
#include <memstr.h>
1060 palkovsky 53
#include <print.h>
2000 decky 54
#include <lib/elf.h>
1579 jermar 55
#include <errno.h>
2050 decky 56
#include <func.h>
1288 jermar 57
#include <syscall/copy.h>
1597 palkovsky 58
#include <console/klog.h>
973 palkovsky 59
 
1170 vana 60
#ifndef LOADED_PROG_STACK_PAGES_NO
61
#define LOADED_PROG_STACK_PAGES_NO 1
62
#endif
1168 vana 63
 
1636 jermar 64
/** Spinlock protecting the tasks_btree B+tree. */
623 jermar 65
SPINLOCK_INITIALIZE(tasks_lock);
1636 jermar 66
 
67
/** B+tree of active tasks.
68
 *
2087 jermar 69
 * The task is guaranteed to exist after it was found in the tasks_btree as
70
 * long as:
1636 jermar 71
 * @li the tasks_lock is held,
2087 jermar 72
 * @li the task's lock is held when task's lock is acquired before releasing
73
 *     tasks_lock or
1880 jermar 74
 * @li the task's refcount is greater than 0
1636 jermar 75
 *
76
 */
1159 jermar 77
btree_t tasks_btree;
1636 jermar 78
 
1005 palkovsky 79
static task_id_t task_counter = 0;
1 jermar 80
 
1585 jermar 81
static void ktaskclnp(void *arg);
1661 jermar 82
static void ktaskgc(void *arg);
1579 jermar 83
 
107 decky 84
/** Initialize tasks
85
 *
86
 * Initialize kernel tasks support.
87
 *
88
 */
1 jermar 89
void task_init(void)
90
{
15 jermar 91
    TASK = NULL;
1159 jermar 92
    btree_create(&tasks_btree);
1 jermar 93
}
94
 
107 decky 95
 
96
/** Create new task
97
 *
98
 * Create new task with no threads.
99
 *
703 jermar 100
 * @param as Task's address space.
1062 jermar 101
 * @param name Symbolic name.
107 decky 102
 *
973 palkovsky 103
 * @return New task's structure
107 decky 104
 *
105
 */
1062 jermar 106
task_t *task_create(as_t *as, char *name)
1 jermar 107
{
413 jermar 108
    ipl_t ipl;
1 jermar 109
    task_t *ta;
1040 palkovsky 110
    int i;
1 jermar 111
 
822 palkovsky 112
    ta = (task_t *) malloc(sizeof(task_t), 0);
113
 
1185 jermar 114
    task_create_arch(ta);
115
 
822 palkovsky 116
    spinlock_initialize(&ta->lock, "task_ta_lock");
117
    list_initialize(&ta->th_head);
118
    ta->as = as;
1062 jermar 119
    ta->name = name;
1585 jermar 120
    ta->main_thread = NULL;
1579 jermar 121
    ta->refcount = 0;
1839 decky 122
    ta->context = CONTEXT;
1579 jermar 123
 
1174 jermar 124
    ta->capabilities = 0;
1579 jermar 125
    ta->accept_new_threads = true;
2039 decky 126
    ta->cycles = 0;
1040 palkovsky 127
 
955 palkovsky 128
    ipc_answerbox_init(&ta->answerbox);
1839 decky 129
    for (i = 0; i < IPC_MAX_PHONES; i++)
1040 palkovsky 130
        ipc_phone_init(&ta->phones[i]);
2087 jermar 131
    if ((ipc_phone_0) && (context_check(ipc_phone_0->task->context,
132
        ta->context)))
1040 palkovsky 133
        ipc_phone_connect(&ta->phones[0], ipc_phone_0);
998 palkovsky 134
    atomic_set(&ta->active_calls, 0);
1460 jermar 135
 
136
    mutex_initialize(&ta->futexes_lock);
137
    btree_create(&ta->futexes);
822 palkovsky 138
 
139
    ipl = interrupts_disable();
1468 jermar 140
 
141
    /*
142
     * Increment address space reference count.
143
     * TODO: Reconsider the locking scheme.
144
     */
145
    mutex_lock(&as->lock);
146
    as->refcount++;
147
    mutex_unlock(&as->lock);
148
 
822 palkovsky 149
    spinlock_lock(&tasks_lock);
1005 palkovsky 150
 
151
    ta->taskid = ++task_counter;
1177 jermar 152
    btree_insert(&tasks_btree, (btree_key_t) ta->taskid, (void *) ta, NULL);
1005 palkovsky 153
 
822 palkovsky 154
    spinlock_unlock(&tasks_lock);
155
    interrupts_restore(ipl);
156
 
1 jermar 157
    return ta;
158
}
159
 
1579 jermar 160
/** Destroy task.
161
 *
162
 * @param t Task to be destroyed.
163
 */
164
void task_destroy(task_t *t)
165
{
1587 jermar 166
    task_destroy_arch(t);
167
    btree_destroy(&t->futexes);
168
 
169
    mutex_lock_active(&t->as->lock);
170
    if (--t->as->refcount == 0) {
171
        mutex_unlock(&t->as->lock);
172
        as_destroy(t->as);
173
        /*
174
         * t->as is destroyed.
175
         */
2040 decky 176
    } else
1587 jermar 177
        mutex_unlock(&t->as->lock);
178
 
179
    free(t);
180
    TASK = NULL;
1579 jermar 181
}
182
 
973 palkovsky 183
/** Create new task with 1 thread and run it
184
 *
1248 jermar 185
 * @param program_addr Address of program executable image.
1062 jermar 186
 * @param name Program name.
187
 *
1229 jermar 188
 * @return Task of the running program or NULL on error.
973 palkovsky 189
 */
1062 jermar 190
task_t * task_run_program(void *program_addr, char *name)
973 palkovsky 191
{
192
    as_t *as;
193
    as_area_t *a;
194
    int rc;
1585 jermar 195
    thread_t *t1, *t2;
973 palkovsky 196
    task_t *task;
1078 jermar 197
    uspace_arg_t *kernel_uarg;
973 palkovsky 198
 
199
    as = as_create(0);
1115 jermar 200
    ASSERT(as);
973 palkovsky 201
 
1025 palkovsky 202
    rc = elf_load((elf_header_t *) program_addr, as);
973 palkovsky 203
    if (rc != EE_OK) {
1468 jermar 204
        as_destroy(as);
973 palkovsky 205
        return NULL;
206
    }
207
 
1078 jermar 208
    kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0);
2087 jermar 209
    kernel_uarg->uspace_entry =
210
        (void *) ((elf_header_t *) program_addr)->e_entry;
1078 jermar 211
    kernel_uarg->uspace_stack = (void *) USTACK_ADDRESS;
212
    kernel_uarg->uspace_thread_function = NULL;
213
    kernel_uarg->uspace_thread_arg = NULL;
214
    kernel_uarg->uspace_uarg = NULL;
1066 jermar 215
 
1062 jermar 216
    task = task_create(as, name);
1115 jermar 217
    ASSERT(task);
218
 
973 palkovsky 219
    /*
220
     * Create the data as_area.
221
     */
2087 jermar 222
    a = as_area_create(as, AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE,
223
        LOADED_PROG_STACK_PAGES_NO * PAGE_SIZE, USTACK_ADDRESS,
224
        AS_AREA_ATTR_NONE, &anon_backend, NULL);
1115 jermar 225
 
1585 jermar 226
    /*
227
     * Create the main thread.
228
     */
2087 jermar 229
    t1 = thread_create(uinit, kernel_uarg, task, THREAD_FLAG_USPACE,
230
        "uinit", false);
1585 jermar 231
    ASSERT(t1);
973 palkovsky 232
 
1585 jermar 233
    /*
234
     * Create killer thread for the new task.
235
     */
2042 decky 236
    t2 = thread_create(ktaskgc, t1, task, 0, "ktaskgc", true);
1585 jermar 237
    ASSERT(t2);
238
    thread_ready(t2);
239
 
240
    thread_ready(t1);
241
 
973 palkovsky 242
    return task;
243
}
1060 palkovsky 244
 
1176 jermar 245
/** Syscall for reading task ID from userspace.
246
 *
2087 jermar 247
 * @param uspace_task_id Userspace address of 8-byte buffer where to store
248
 * current task ID.
1176 jermar 249
 *
1288 jermar 250
 * @return 0 on success or an error code from @ref errno.h.
1176 jermar 251
 */
1780 jermar 252
unative_t sys_task_get_id(task_id_t *uspace_task_id)
1176 jermar 253
{
254
    /*
255
     * No need to acquire lock on TASK because taskid
256
     * remains constant for the lifespan of the task.
257
     */
2087 jermar 258
    return (unative_t) copy_to_uspace(uspace_task_id, &TASK->taskid,
259
        sizeof(TASK->taskid));
1176 jermar 260
}
261
 
1178 jermar 262
/** Find task structure corresponding to task ID.
263
 *
264
 * The tasks_lock must be already held by the caller of this function
265
 * and interrupts must be disabled.
266
 *
267
 * @param id Task ID.
268
 *
269
 * @return Task structure address or NULL if there is no such task ID.
270
 */
271
task_t *task_find_by_id(task_id_t id)
272
{
273
    btree_node_t *leaf;
274
 
275
    return (task_t *) btree_search(&tasks_btree, (btree_key_t) id, &leaf);
276
}
277
 
2039 decky 278
/** Get accounting data of given task.
279
 *
2048 jermar 280
 * Note that task lock of 't' must be already held and
2039 decky 281
 * interrupts must be already disabled.
282
 *
283
 * @param t Pointer to thread.
284
 *
285
 */
286
uint64_t task_get_accounting(task_t *t)
287
{
288
    /* Accumulated value of task */
289
    uint64_t ret = t->cycles;
290
 
291
    /* Current values of threads */
292
    link_t *cur;
293
    for (cur = t->th_head.next; cur != &t->th_head; cur = cur->next) {
294
        thread_t *thr = list_get_instance(cur, thread_t, th_link);
295
 
296
        spinlock_lock(&thr->lock);
2042 decky 297
        /* Process only counted threads */
298
        if (!thr->uncounted) {
2087 jermar 299
            if (thr == THREAD) {
300
                /* Update accounting of current thread */
301
                thread_update_accounting();
302
            }
2042 decky 303
            ret += thr->cycles;
304
        }
2039 decky 305
        spinlock_unlock(&thr->lock);
306
    }
307
 
308
    return ret;
309
}
310
 
1579 jermar 311
/** Kill task.
312
 *
313
 * @param id ID of the task to be killed.
314
 *
315
 * @return 0 on success or an error code from errno.h
316
 */
317
int task_kill(task_id_t id)
318
{
319
    ipl_t ipl;
320
    task_t *ta;
321
    thread_t *t;
322
    link_t *cur;
1600 jermar 323
 
324
    if (id == 1)
325
        return EPERM;
1579 jermar 326
 
327
    ipl = interrupts_disable();
328
    spinlock_lock(&tasks_lock);
329
 
330
    if (!(ta = task_find_by_id(id))) {
331
        spinlock_unlock(&tasks_lock);
332
        interrupts_restore(ipl);
333
        return ENOENT;
334
    }
1588 jermar 335
 
1579 jermar 336
    spinlock_lock(&ta->lock);
337
    ta->refcount++;
338
    spinlock_unlock(&ta->lock);
1587 jermar 339
 
1588 jermar 340
    btree_remove(&tasks_btree, ta->taskid, NULL);
1587 jermar 341
    spinlock_unlock(&tasks_lock);
1579 jermar 342
 
2042 decky 343
    t = thread_create(ktaskclnp, NULL, ta, 0, "ktaskclnp", true);
1579 jermar 344
 
345
    spinlock_lock(&ta->lock);
1580 jermar 346
    ta->accept_new_threads = false;
1579 jermar 347
    ta->refcount--;
1585 jermar 348
 
349
    /*
1687 jermar 350
     * Interrupt all threads except ktaskclnp.
1585 jermar 351
     */
1579 jermar 352
    for (cur = ta->th_head.next; cur != &ta->th_head; cur = cur->next) {
353
        thread_t *thr;
354
        bool  sleeping = false;
355
 
356
        thr = list_get_instance(cur, thread_t, th_link);
357
        if (thr == t)
358
            continue;
359
 
360
        spinlock_lock(&thr->lock);
361
        thr->interrupted = true;
362
        if (thr->state == Sleeping)
363
            sleeping = true;
364
        spinlock_unlock(&thr->lock);
365
 
366
        if (sleeping)
2109 jermar 367
            waitq_interrupt_sleep(thr);
1579 jermar 368
    }
369
 
1580 jermar 370
    spinlock_unlock(&ta->lock);
371
    interrupts_restore(ipl);
1579 jermar 372
 
1580 jermar 373
    if (t)
374
        thread_ready(t);
375
 
1579 jermar 376
    return 0;
377
}
378
 
1060 palkovsky 379
/** Print task list */
380
void task_print_list(void)
381
{
382
    link_t *cur;
383
    ipl_t ipl;
384
 
385
    /* Messing with thread structures, avoid deadlock */
386
    ipl = interrupts_disable();
387
    spinlock_lock(&tasks_lock);
2035 decky 388
 
2087 jermar 389
    printf("taskid name       ctx address    as         cycles     threads "
390
        "calls  callee\n");
391
    printf("------ ---------- --- ---------- ---------- ---------- ------- "        "------ ------>\n");
1060 palkovsky 392
 
2087 jermar 393
    for (cur = tasks_btree.leaf_head.next; cur != &tasks_btree.leaf_head;
394
        cur = cur->next) {
1159 jermar 395
        btree_node_t *node;
2118 decky 396
        unsigned int i;
1159 jermar 397
 
398
        node = list_get_instance(cur, btree_node_t, leaf_link);
399
        for (i = 0; i < node->keys; i++) {
400
            task_t *t;
401
            int j;
402
 
403
            t = (task_t *) node->value[i];
404
 
405
            spinlock_lock(&t->lock);
2039 decky 406
 
2050 decky 407
            uint64_t cycles;
2039 decky 408
            char suffix;
2050 decky 409
            order(task_get_accounting(t), &cycles, &suffix);
2039 decky 410
 
2087 jermar 411
            printf("%-6lld %-10s %-3ld %#10zx %#10zx %9llu%c %7zd "
412
                "%6zd", t->taskid, t->name, t->context, t, t->as,
413
                cycles, suffix, t->refcount,
414
                atomic_get(&t->active_calls));
2035 decky 415
            for (j = 0; j < IPC_MAX_PHONES; j++) {
1159 jermar 416
                if (t->phones[j].callee)
2087 jermar 417
                    printf(" %zd:%#zx", j,
418
                        t->phones[j].callee);
1159 jermar 419
            }
420
            printf("\n");
2039 decky 421
 
1159 jermar 422
            spinlock_unlock(&t->lock);
1060 palkovsky 423
        }
424
    }
425
 
426
    spinlock_unlock(&tasks_lock);
427
    interrupts_restore(ipl);
428
}
1579 jermar 429
 
1585 jermar 430
/** Kernel thread used to cleanup the task after it is killed. */
1580 jermar 431
void ktaskclnp(void *arg)
1579 jermar 432
{
1580 jermar 433
    ipl_t ipl;
1585 jermar 434
    thread_t *t = NULL, *main_thread;
1580 jermar 435
    link_t *cur;
1661 jermar 436
    bool again;
1580 jermar 437
 
438
    thread_detach(THREAD);
439
 
440
loop:
441
    ipl = interrupts_disable();
442
    spinlock_lock(&TASK->lock);
443
 
1585 jermar 444
    main_thread = TASK->main_thread;
445
 
1579 jermar 446
    /*
1580 jermar 447
     * Find a thread to join.
448
     */
1661 jermar 449
    again = false;
1580 jermar 450
    for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {
451
        t = list_get_instance(cur, thread_t, th_link);
1661 jermar 452
 
453
        spinlock_lock(&t->lock);
454
        if (t == THREAD) {
455
            spinlock_unlock(&t->lock);
1580 jermar 456
            continue;
1661 jermar 457
        } else if (t == main_thread) {
458
            spinlock_unlock(&t->lock);
1585 jermar 459
            continue;
1661 jermar 460
        } else if (t->join_type != None) {
461
            spinlock_unlock(&t->lock);
462
            again = true;
463
            continue;
464
        } else {
465
            t->join_type = TaskClnp;
466
            spinlock_unlock(&t->lock);
467
            again = false;
1580 jermar 468
            break;
1661 jermar 469
        }
1580 jermar 470
    }
471
 
472
    spinlock_unlock(&TASK->lock);
473
    interrupts_restore(ipl);
474
 
1661 jermar 475
    if (again) {
476
        /*
477
         * Other cleanup (e.g. ktaskgc) is in progress.
478
         */
479
        scheduler();
480
        goto loop;
481
    }
482
 
1580 jermar 483
    if (t != THREAD) {
2087 jermar 484
        ASSERT(t != main_thread);   /* uninit is joined and detached
485
                         * in ktaskgc */
1580 jermar 486
        thread_join(t);
487
        thread_detach(t);
2087 jermar 488
        goto loop;          /* go for another thread */
1580 jermar 489
    }
490
 
491
    /*
492
     * Now there are no other threads in this task
493
     * and no new threads can be created.
494
     */
1880 jermar 495
 
1583 jermar 496
    ipc_cleanup();
497
    futex_cleanup();
1597 palkovsky 498
    klog_printf("Cleanup of task %lld completed.", TASK->taskid);
1579 jermar 499
}
1585 jermar 500
 
1684 jermar 501
/** Kernel thread used to kill the userspace task when its main thread exits.
1585 jermar 502
 *
503
 * This thread waits until the main userspace thread (i.e. uninit) exits.
1661 jermar 504
 * When this happens, the task is killed. In the meantime, exited threads
505
 * are garbage collected.
1585 jermar 506
 *
507
 * @param arg Pointer to the thread structure of the task's main thread.
508
 */
1661 jermar 509
void ktaskgc(void *arg)
1585 jermar 510
{
511
    thread_t *t = (thread_t *) arg;
1661 jermar 512
loop:  
1585 jermar 513
    /*
514
     * Userspace threads cannot detach themselves,
515
     * therefore the thread pointer is guaranteed to be valid.
516
     */
2087 jermar 517
    if (thread_join_timeout(t, 1000000, SYNCH_FLAGS_NONE) ==
518
        ESYNCH_TIMEOUT) {   /* sleep uninterruptibly here! */
1661 jermar 519
        ipl_t ipl;
520
        link_t *cur;
521
        thread_t *thr = NULL;
522
 
523
        /*
2087 jermar 524
         * The join timed out. Try to do some garbage collection of
525
         * Undead threads.
1661 jermar 526
         */
527
more_gc:       
528
        ipl = interrupts_disable();
529
        spinlock_lock(&TASK->lock);
530
 
2087 jermar 531
        for (cur = TASK->th_head.next; cur != &TASK->th_head;
532
            cur = cur->next) {
1661 jermar 533
            thr = list_get_instance(cur, thread_t, th_link);
534
            spinlock_lock(&thr->lock);
2087 jermar 535
            if (thr != t && thr->state == Undead &&
536
                thr->join_type == None) {
1661 jermar 537
                thr->join_type = TaskGC;
538
                spinlock_unlock(&thr->lock);
539
                break;
540
            }
541
            spinlock_unlock(&thr->lock);
542
            thr = NULL;
543
        }
544
        spinlock_unlock(&TASK->lock);
1676 jermar 545
        interrupts_restore(ipl);
1661 jermar 546
 
547
        if (thr) {
548
            thread_join(thr);
549
            thread_detach(thr);
550
            scheduler();
551
            goto more_gc;
552
        }
553
 
554
        goto loop;
555
    }
1585 jermar 556
    thread_detach(t);
557
    task_kill(TASK->taskid);
558
}
1702 cejka 559
 
1757 jermar 560
/** @}
1702 cejka 561
 */