| 1 | /* $NetBSD: sys_lwp.c,v 1.57 2015/07/24 13:02:52 maxv Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2001, 2006, 2007, 2008 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Nathan J. Williams, and Andrew Doran. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | /* |
| 33 | * Lightweight process (LWP) system calls. See kern_lwp.c for a description |
| 34 | * of LWPs. |
| 35 | */ |
| 36 | |
| 37 | #include <sys/cdefs.h> |
| 38 | __KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v 1.57 2015/07/24 13:02:52 maxv Exp $" ); |
| 39 | |
| 40 | #include <sys/param.h> |
| 41 | #include <sys/systm.h> |
| 42 | #include <sys/pool.h> |
| 43 | #include <sys/proc.h> |
| 44 | #include <sys/types.h> |
| 45 | #include <sys/syscallargs.h> |
| 46 | #include <sys/kauth.h> |
| 47 | #include <sys/kmem.h> |
| 48 | #include <sys/sleepq.h> |
| 49 | #include <sys/lwpctl.h> |
| 50 | #include <sys/cpu.h> |
| 51 | |
| 52 | #include <uvm/uvm_extern.h> |
| 53 | |
| 54 | #define LWP_UNPARK_MAX 1024 |
| 55 | |
| 56 | static syncobj_t lwp_park_sobj = { |
| 57 | SOBJ_SLEEPQ_LIFO, |
| 58 | sleepq_unsleep, |
| 59 | sleepq_changepri, |
| 60 | sleepq_lendpri, |
| 61 | syncobj_noowner, |
| 62 | }; |
| 63 | |
| 64 | static sleeptab_t lwp_park_tab; |
| 65 | |
| 66 | void |
| 67 | lwp_sys_init(void) |
| 68 | { |
| 69 | sleeptab_init(&lwp_park_tab); |
| 70 | } |
| 71 | |
| 72 | int |
| 73 | do_lwp_create(lwp_t *l, void *arg, u_long flags, lwpid_t *new_lwp) |
| 74 | { |
| 75 | struct proc *p = l->l_proc; |
| 76 | struct lwp *l2; |
| 77 | struct schedstate_percpu *spc; |
| 78 | vaddr_t uaddr; |
| 79 | int error; |
| 80 | |
| 81 | /* XXX check against resource limits */ |
| 82 | |
| 83 | uaddr = uvm_uarea_alloc(); |
| 84 | if (__predict_false(uaddr == 0)) |
| 85 | return ENOMEM; |
| 86 | |
| 87 | error = lwp_create(l, p, uaddr, flags & LWP_DETACHED, |
| 88 | NULL, 0, p->p_emul->e_startlwp, arg, &l2, l->l_class); |
| 89 | if (__predict_false(error)) { |
| 90 | uvm_uarea_free(uaddr); |
| 91 | return error; |
| 92 | } |
| 93 | |
| 94 | *new_lwp = l2->l_lid; |
| 95 | |
| 96 | /* |
| 97 | * Set the new LWP running, unless the caller has requested that |
| 98 | * it be created in suspended state. If the process is stopping, |
| 99 | * then the LWP is created stopped. |
| 100 | */ |
| 101 | mutex_enter(p->p_lock); |
| 102 | lwp_lock(l2); |
| 103 | spc = &l2->l_cpu->ci_schedstate; |
| 104 | if ((flags & LWP_SUSPENDED) == 0 && |
| 105 | (l->l_flag & (LW_WREBOOT | LW_WSUSPEND | LW_WEXIT)) == 0) { |
| 106 | if (p->p_stat == SSTOP || (p->p_sflag & PS_STOPPING) != 0) { |
| 107 | KASSERT(l2->l_wchan == NULL); |
| 108 | l2->l_stat = LSSTOP; |
| 109 | p->p_nrlwps--; |
| 110 | lwp_unlock_to(l2, spc->spc_lwplock); |
| 111 | } else { |
| 112 | KASSERT(lwp_locked(l2, spc->spc_mutex)); |
| 113 | l2->l_stat = LSRUN; |
| 114 | sched_enqueue(l2, false); |
| 115 | lwp_unlock(l2); |
| 116 | } |
| 117 | } else { |
| 118 | l2->l_stat = LSSUSPENDED; |
| 119 | p->p_nrlwps--; |
| 120 | lwp_unlock_to(l2, spc->spc_lwplock); |
| 121 | } |
| 122 | mutex_exit(p->p_lock); |
| 123 | |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | int |
| 128 | sys__lwp_create(struct lwp *l, const struct sys__lwp_create_args *uap, |
| 129 | register_t *retval) |
| 130 | { |
| 131 | /* { |
| 132 | syscallarg(const ucontext_t *) ucp; |
| 133 | syscallarg(u_long) flags; |
| 134 | syscallarg(lwpid_t *) new_lwp; |
| 135 | } */ |
| 136 | struct proc *p = l->l_proc; |
| 137 | ucontext_t *newuc; |
| 138 | lwpid_t lid; |
| 139 | int error; |
| 140 | |
| 141 | newuc = kmem_alloc(sizeof(ucontext_t), KM_SLEEP); |
| 142 | error = copyin(SCARG(uap, ucp), newuc, p->p_emul->e_ucsize); |
| 143 | if (error) |
| 144 | goto fail; |
| 145 | |
| 146 | /* validate the ucontext */ |
| 147 | if ((newuc->uc_flags & _UC_CPU) == 0) { |
| 148 | error = EINVAL; |
| 149 | goto fail; |
| 150 | } |
| 151 | error = cpu_mcontext_validate(l, &newuc->uc_mcontext); |
| 152 | if (error) |
| 153 | goto fail; |
| 154 | |
| 155 | error = do_lwp_create(l, newuc, SCARG(uap, flags), &lid); |
| 156 | if (error) |
| 157 | goto fail; |
| 158 | |
| 159 | /* |
| 160 | * do not free ucontext in case of an error here, |
| 161 | * the lwp will actually run and access it |
| 162 | */ |
| 163 | return copyout(&lid, SCARG(uap, new_lwp), sizeof(lid)); |
| 164 | |
| 165 | fail: |
| 166 | kmem_free(newuc, sizeof(ucontext_t)); |
| 167 | return error; |
| 168 | } |
| 169 | |
| 170 | int |
| 171 | sys__lwp_exit(struct lwp *l, const void *v, register_t *retval) |
| 172 | { |
| 173 | |
| 174 | lwp_exit(l); |
| 175 | return 0; |
| 176 | } |
| 177 | |
| 178 | int |
| 179 | sys__lwp_self(struct lwp *l, const void *v, register_t *retval) |
| 180 | { |
| 181 | |
| 182 | *retval = l->l_lid; |
| 183 | return 0; |
| 184 | } |
| 185 | |
| 186 | int |
| 187 | sys__lwp_getprivate(struct lwp *l, const void *v, register_t *retval) |
| 188 | { |
| 189 | |
| 190 | *retval = (uintptr_t)l->l_private; |
| 191 | return 0; |
| 192 | } |
| 193 | |
| 194 | int |
| 195 | sys__lwp_setprivate(struct lwp *l, const struct sys__lwp_setprivate_args *uap, |
| 196 | register_t *retval) |
| 197 | { |
| 198 | /* { |
| 199 | syscallarg(void *) ptr; |
| 200 | } */ |
| 201 | |
| 202 | return lwp_setprivate(l, SCARG(uap, ptr)); |
| 203 | } |
| 204 | |
| 205 | int |
| 206 | sys__lwp_suspend(struct lwp *l, const struct sys__lwp_suspend_args *uap, |
| 207 | register_t *retval) |
| 208 | { |
| 209 | /* { |
| 210 | syscallarg(lwpid_t) target; |
| 211 | } */ |
| 212 | struct proc *p = l->l_proc; |
| 213 | struct lwp *t; |
| 214 | int error; |
| 215 | |
| 216 | mutex_enter(p->p_lock); |
| 217 | if ((t = lwp_find(p, SCARG(uap, target))) == NULL) { |
| 218 | mutex_exit(p->p_lock); |
| 219 | return ESRCH; |
| 220 | } |
| 221 | |
| 222 | /* |
| 223 | * Check for deadlock, which is only possible when we're suspending |
| 224 | * ourself. XXX There is a short race here, as p_nrlwps is only |
| 225 | * incremented when an LWP suspends itself on the kernel/user |
| 226 | * boundary. It's still possible to kill -9 the process so we |
| 227 | * don't bother checking further. |
| 228 | */ |
| 229 | lwp_lock(t); |
| 230 | if ((t == l && p->p_nrlwps == 1) || |
| 231 | (l->l_flag & (LW_WCORE | LW_WEXIT)) != 0) { |
| 232 | lwp_unlock(t); |
| 233 | mutex_exit(p->p_lock); |
| 234 | return EDEADLK; |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * Suspend the LWP. XXX If it's on a different CPU, we should wait |
| 239 | * for it to be preempted, where it will put itself to sleep. |
| 240 | * |
| 241 | * Suspension of the current LWP will happen on return to userspace. |
| 242 | */ |
| 243 | error = lwp_suspend(l, t); |
| 244 | if (error) { |
| 245 | mutex_exit(p->p_lock); |
| 246 | return error; |
| 247 | } |
| 248 | |
| 249 | /* |
| 250 | * Wait for: |
| 251 | * o process exiting |
| 252 | * o target LWP suspended |
| 253 | * o target LWP not suspended and L_WSUSPEND clear |
| 254 | * o target LWP exited |
| 255 | */ |
| 256 | for (;;) { |
| 257 | error = cv_wait_sig(&p->p_lwpcv, p->p_lock); |
| 258 | if (error) { |
| 259 | error = ERESTART; |
| 260 | break; |
| 261 | } |
| 262 | if (lwp_find(p, SCARG(uap, target)) == NULL) { |
| 263 | error = ESRCH; |
| 264 | break; |
| 265 | } |
| 266 | if ((l->l_flag | t->l_flag) & (LW_WCORE | LW_WEXIT)) { |
| 267 | error = ERESTART; |
| 268 | break; |
| 269 | } |
| 270 | if (t->l_stat == LSSUSPENDED || |
| 271 | (t->l_flag & LW_WSUSPEND) == 0) |
| 272 | break; |
| 273 | } |
| 274 | mutex_exit(p->p_lock); |
| 275 | |
| 276 | return error; |
| 277 | } |
| 278 | |
| 279 | int |
| 280 | sys__lwp_continue(struct lwp *l, const struct sys__lwp_continue_args *uap, |
| 281 | register_t *retval) |
| 282 | { |
| 283 | /* { |
| 284 | syscallarg(lwpid_t) target; |
| 285 | } */ |
| 286 | int error; |
| 287 | struct proc *p = l->l_proc; |
| 288 | struct lwp *t; |
| 289 | |
| 290 | error = 0; |
| 291 | |
| 292 | mutex_enter(p->p_lock); |
| 293 | if ((t = lwp_find(p, SCARG(uap, target))) == NULL) { |
| 294 | mutex_exit(p->p_lock); |
| 295 | return ESRCH; |
| 296 | } |
| 297 | |
| 298 | lwp_lock(t); |
| 299 | lwp_continue(t); |
| 300 | mutex_exit(p->p_lock); |
| 301 | |
| 302 | return error; |
| 303 | } |
| 304 | |
| 305 | int |
| 306 | sys__lwp_wakeup(struct lwp *l, const struct sys__lwp_wakeup_args *uap, |
| 307 | register_t *retval) |
| 308 | { |
| 309 | /* { |
| 310 | syscallarg(lwpid_t) target; |
| 311 | } */ |
| 312 | struct lwp *t; |
| 313 | struct proc *p; |
| 314 | int error; |
| 315 | |
| 316 | p = l->l_proc; |
| 317 | mutex_enter(p->p_lock); |
| 318 | |
| 319 | if ((t = lwp_find(p, SCARG(uap, target))) == NULL) { |
| 320 | mutex_exit(p->p_lock); |
| 321 | return ESRCH; |
| 322 | } |
| 323 | |
| 324 | lwp_lock(t); |
| 325 | t->l_flag |= (LW_CANCELLED | LW_UNPARKED); |
| 326 | |
| 327 | if (t->l_stat != LSSLEEP) { |
| 328 | lwp_unlock(t); |
| 329 | error = ENODEV; |
| 330 | } else if ((t->l_flag & LW_SINTR) == 0) { |
| 331 | lwp_unlock(t); |
| 332 | error = EBUSY; |
| 333 | } else { |
| 334 | /* Wake it up. lwp_unsleep() will release the LWP lock. */ |
| 335 | lwp_unsleep(t, true); |
| 336 | error = 0; |
| 337 | } |
| 338 | |
| 339 | mutex_exit(p->p_lock); |
| 340 | |
| 341 | return error; |
| 342 | } |
| 343 | |
| 344 | int |
| 345 | sys__lwp_wait(struct lwp *l, const struct sys__lwp_wait_args *uap, |
| 346 | register_t *retval) |
| 347 | { |
| 348 | /* { |
| 349 | syscallarg(lwpid_t) wait_for; |
| 350 | syscallarg(lwpid_t *) departed; |
| 351 | } */ |
| 352 | struct proc *p = l->l_proc; |
| 353 | int error; |
| 354 | lwpid_t dep; |
| 355 | |
| 356 | mutex_enter(p->p_lock); |
| 357 | error = lwp_wait(l, SCARG(uap, wait_for), &dep, false); |
| 358 | mutex_exit(p->p_lock); |
| 359 | |
| 360 | if (!error && SCARG(uap, departed)) { |
| 361 | error = copyout(&dep, SCARG(uap, departed), sizeof(dep)); |
| 362 | } |
| 363 | |
| 364 | return error; |
| 365 | } |
| 366 | |
| 367 | int |
| 368 | sys__lwp_kill(struct lwp *l, const struct sys__lwp_kill_args *uap, |
| 369 | register_t *retval) |
| 370 | { |
| 371 | /* { |
| 372 | syscallarg(lwpid_t) target; |
| 373 | syscallarg(int) signo; |
| 374 | } */ |
| 375 | struct proc *p = l->l_proc; |
| 376 | struct lwp *t; |
| 377 | ksiginfo_t ksi; |
| 378 | int signo = SCARG(uap, signo); |
| 379 | int error = 0; |
| 380 | |
| 381 | if ((u_int)signo >= NSIG) |
| 382 | return EINVAL; |
| 383 | |
| 384 | KSI_INIT(&ksi); |
| 385 | ksi.ksi_signo = signo; |
| 386 | ksi.ksi_code = SI_LWP; |
| 387 | ksi.ksi_pid = p->p_pid; |
| 388 | ksi.ksi_uid = kauth_cred_geteuid(l->l_cred); |
| 389 | ksi.ksi_lid = SCARG(uap, target); |
| 390 | |
| 391 | mutex_enter(proc_lock); |
| 392 | mutex_enter(p->p_lock); |
| 393 | if ((t = lwp_find(p, ksi.ksi_lid)) == NULL) |
| 394 | error = ESRCH; |
| 395 | else if (signo != 0) |
| 396 | kpsignal2(p, &ksi); |
| 397 | mutex_exit(p->p_lock); |
| 398 | mutex_exit(proc_lock); |
| 399 | |
| 400 | return error; |
| 401 | } |
| 402 | |
| 403 | int |
| 404 | sys__lwp_detach(struct lwp *l, const struct sys__lwp_detach_args *uap, |
| 405 | register_t *retval) |
| 406 | { |
| 407 | /* { |
| 408 | syscallarg(lwpid_t) target; |
| 409 | } */ |
| 410 | struct proc *p; |
| 411 | struct lwp *t; |
| 412 | lwpid_t target; |
| 413 | int error; |
| 414 | |
| 415 | target = SCARG(uap, target); |
| 416 | p = l->l_proc; |
| 417 | |
| 418 | mutex_enter(p->p_lock); |
| 419 | |
| 420 | if (l->l_lid == target) |
| 421 | t = l; |
| 422 | else { |
| 423 | /* |
| 424 | * We can't use lwp_find() here because the target might |
| 425 | * be a zombie. |
| 426 | */ |
| 427 | LIST_FOREACH(t, &p->p_lwps, l_sibling) |
| 428 | if (t->l_lid == target) |
| 429 | break; |
| 430 | } |
| 431 | |
| 432 | /* |
| 433 | * If the LWP is already detached, there's nothing to do. |
| 434 | * If it's a zombie, we need to clean up after it. LSZOMB |
| 435 | * is visible with the proc mutex held. |
| 436 | * |
| 437 | * After we have detached or released the LWP, kick any |
| 438 | * other LWPs that may be sitting in _lwp_wait(), waiting |
| 439 | * for the target LWP to exit. |
| 440 | */ |
| 441 | if (t != NULL && t->l_stat != LSIDL) { |
| 442 | if ((t->l_prflag & LPR_DETACHED) == 0) { |
| 443 | p->p_ndlwps++; |
| 444 | t->l_prflag |= LPR_DETACHED; |
| 445 | if (t->l_stat == LSZOMB) { |
| 446 | /* Releases proc mutex. */ |
| 447 | lwp_free(t, false, false); |
| 448 | return 0; |
| 449 | } |
| 450 | error = 0; |
| 451 | |
| 452 | /* |
| 453 | * Have any LWPs sleeping in lwp_wait() recheck |
| 454 | * for deadlock. |
| 455 | */ |
| 456 | cv_broadcast(&p->p_lwpcv); |
| 457 | } else |
| 458 | error = EINVAL; |
| 459 | } else |
| 460 | error = ESRCH; |
| 461 | |
| 462 | mutex_exit(p->p_lock); |
| 463 | |
| 464 | return error; |
| 465 | } |
| 466 | |
| 467 | static inline wchan_t |
| 468 | lwp_park_wchan(struct proc *p, const void *hint) |
| 469 | { |
| 470 | |
| 471 | return (wchan_t)((uintptr_t)p ^ (uintptr_t)hint); |
| 472 | } |
| 473 | |
| 474 | int |
| 475 | lwp_unpark(lwpid_t target, const void *hint) |
| 476 | { |
| 477 | sleepq_t *sq; |
| 478 | wchan_t wchan; |
| 479 | kmutex_t *mp; |
| 480 | proc_t *p; |
| 481 | lwp_t *t; |
| 482 | |
| 483 | /* |
| 484 | * Easy case: search for the LWP on the sleep queue. If |
| 485 | * it's parked, remove it from the queue and set running. |
| 486 | */ |
| 487 | p = curproc; |
| 488 | wchan = lwp_park_wchan(p, hint); |
| 489 | sq = sleeptab_lookup(&lwp_park_tab, wchan, &mp); |
| 490 | |
| 491 | TAILQ_FOREACH(t, sq, l_sleepchain) |
| 492 | if (t->l_proc == p && t->l_lid == target) |
| 493 | break; |
| 494 | |
| 495 | if (__predict_true(t != NULL)) { |
| 496 | sleepq_remove(sq, t); |
| 497 | mutex_spin_exit(mp); |
| 498 | return 0; |
| 499 | } |
| 500 | |
| 501 | /* |
| 502 | * The LWP hasn't parked yet. Take the hit and mark the |
| 503 | * operation as pending. |
| 504 | */ |
| 505 | mutex_spin_exit(mp); |
| 506 | |
| 507 | mutex_enter(p->p_lock); |
| 508 | if ((t = lwp_find(p, target)) == NULL) { |
| 509 | mutex_exit(p->p_lock); |
| 510 | return ESRCH; |
| 511 | } |
| 512 | |
| 513 | /* |
| 514 | * It may not have parked yet, we may have raced, or it |
| 515 | * is parked on a different user sync object. |
| 516 | */ |
| 517 | lwp_lock(t); |
| 518 | if (t->l_syncobj == &lwp_park_sobj) { |
| 519 | /* Releases the LWP lock. */ |
| 520 | lwp_unsleep(t, true); |
| 521 | } else { |
| 522 | /* |
| 523 | * Set the operation pending. The next call to _lwp_park |
| 524 | * will return early. |
| 525 | */ |
| 526 | t->l_flag |= LW_UNPARKED; |
| 527 | lwp_unlock(t); |
| 528 | } |
| 529 | |
| 530 | mutex_exit(p->p_lock); |
| 531 | return 0; |
| 532 | } |
| 533 | |
| 534 | int |
| 535 | lwp_park(clockid_t clock_id, int flags, struct timespec *ts, const void *hint) |
| 536 | { |
| 537 | sleepq_t *sq; |
| 538 | kmutex_t *mp; |
| 539 | wchan_t wchan; |
| 540 | int timo, error; |
| 541 | lwp_t *l; |
| 542 | |
| 543 | if (ts != NULL) { |
| 544 | if ((error = ts2timo(clock_id, flags, ts, &timo, NULL)) != 0) |
| 545 | return error; |
| 546 | KASSERT(timo != 0); |
| 547 | } else { |
| 548 | timo = 0; |
| 549 | } |
| 550 | |
| 551 | /* Find and lock the sleep queue. */ |
| 552 | l = curlwp; |
| 553 | wchan = lwp_park_wchan(l->l_proc, hint); |
| 554 | sq = sleeptab_lookup(&lwp_park_tab, wchan, &mp); |
| 555 | |
| 556 | /* |
| 557 | * Before going the full route and blocking, check to see if an |
| 558 | * unpark op is pending. |
| 559 | */ |
| 560 | lwp_lock(l); |
| 561 | if ((l->l_flag & (LW_CANCELLED | LW_UNPARKED)) != 0) { |
| 562 | l->l_flag &= ~(LW_CANCELLED | LW_UNPARKED); |
| 563 | lwp_unlock(l); |
| 564 | mutex_spin_exit(mp); |
| 565 | return EALREADY; |
| 566 | } |
| 567 | lwp_unlock_to(l, mp); |
| 568 | l->l_biglocks = 0; |
| 569 | sleepq_enqueue(sq, wchan, "parked" , &lwp_park_sobj); |
| 570 | error = sleepq_block(timo, true); |
| 571 | switch (error) { |
| 572 | case EWOULDBLOCK: |
| 573 | error = ETIMEDOUT; |
| 574 | break; |
| 575 | case ERESTART: |
| 576 | error = EINTR; |
| 577 | break; |
| 578 | default: |
| 579 | /* nothing */ |
| 580 | break; |
| 581 | } |
| 582 | return error; |
| 583 | } |
| 584 | |
| 585 | /* |
| 586 | * 'park' an LWP waiting on a user-level synchronisation object. The LWP |
| 587 | * will remain parked until another LWP in the same process calls in and |
| 588 | * requests that it be unparked. |
| 589 | */ |
| 590 | int |
| 591 | sys____lwp_park60(struct lwp *l, const struct sys____lwp_park60_args *uap, |
| 592 | register_t *retval) |
| 593 | { |
| 594 | /* { |
| 595 | syscallarg(clockid_t) clock_id; |
| 596 | syscallarg(int) flags; |
| 597 | syscallarg(const struct timespec *) ts; |
| 598 | syscallarg(lwpid_t) unpark; |
| 599 | syscallarg(const void *) hint; |
| 600 | syscallarg(const void *) unparkhint; |
| 601 | } */ |
| 602 | struct timespec ts, *tsp; |
| 603 | int error; |
| 604 | |
| 605 | if (SCARG(uap, ts) == NULL) |
| 606 | tsp = NULL; |
| 607 | else { |
| 608 | error = copyin(SCARG(uap, ts), &ts, sizeof(ts)); |
| 609 | if (error != 0) |
| 610 | return error; |
| 611 | tsp = &ts; |
| 612 | } |
| 613 | |
| 614 | if (SCARG(uap, unpark) != 0) { |
| 615 | error = lwp_unpark(SCARG(uap, unpark), SCARG(uap, unparkhint)); |
| 616 | if (error != 0) |
| 617 | return error; |
| 618 | } |
| 619 | |
| 620 | return lwp_park(SCARG(uap, clock_id), SCARG(uap, flags), tsp, |
| 621 | SCARG(uap, hint)); |
| 622 | } |
| 623 | |
| 624 | int |
| 625 | sys__lwp_unpark(struct lwp *l, const struct sys__lwp_unpark_args *uap, |
| 626 | register_t *retval) |
| 627 | { |
| 628 | /* { |
| 629 | syscallarg(lwpid_t) target; |
| 630 | syscallarg(const void *) hint; |
| 631 | } */ |
| 632 | |
| 633 | return lwp_unpark(SCARG(uap, target), SCARG(uap, hint)); |
| 634 | } |
| 635 | |
| 636 | int |
| 637 | sys__lwp_unpark_all(struct lwp *l, const struct sys__lwp_unpark_all_args *uap, |
| 638 | register_t *retval) |
| 639 | { |
| 640 | /* { |
| 641 | syscallarg(const lwpid_t *) targets; |
| 642 | syscallarg(size_t) ntargets; |
| 643 | syscallarg(const void *) hint; |
| 644 | } */ |
| 645 | struct proc *p; |
| 646 | struct lwp *t; |
| 647 | sleepq_t *sq; |
| 648 | wchan_t wchan; |
| 649 | lwpid_t targets[32], *tp, *tpp, *tmax, target; |
| 650 | int error; |
| 651 | kmutex_t *mp; |
| 652 | u_int ntargets; |
| 653 | size_t sz; |
| 654 | |
| 655 | p = l->l_proc; |
| 656 | ntargets = SCARG(uap, ntargets); |
| 657 | |
| 658 | if (SCARG(uap, targets) == NULL) { |
| 659 | /* |
| 660 | * Let the caller know how much we are willing to do, and |
| 661 | * let it unpark the LWPs in blocks. |
| 662 | */ |
| 663 | *retval = LWP_UNPARK_MAX; |
| 664 | return 0; |
| 665 | } |
| 666 | if (ntargets > LWP_UNPARK_MAX || ntargets == 0) |
| 667 | return EINVAL; |
| 668 | |
| 669 | /* |
| 670 | * Copy in the target array. If it's a small number of LWPs, then |
| 671 | * place the numbers on the stack. |
| 672 | */ |
| 673 | sz = sizeof(target) * ntargets; |
| 674 | if (sz <= sizeof(targets)) |
| 675 | tp = targets; |
| 676 | else { |
| 677 | tp = kmem_alloc(sz, KM_SLEEP); |
| 678 | if (tp == NULL) |
| 679 | return ENOMEM; |
| 680 | } |
| 681 | error = copyin(SCARG(uap, targets), tp, sz); |
| 682 | if (error != 0) { |
| 683 | if (tp != targets) { |
| 684 | kmem_free(tp, sz); |
| 685 | } |
| 686 | return error; |
| 687 | } |
| 688 | |
| 689 | wchan = lwp_park_wchan(p, SCARG(uap, hint)); |
| 690 | sq = sleeptab_lookup(&lwp_park_tab, wchan, &mp); |
| 691 | |
| 692 | for (tmax = tp + ntargets, tpp = tp; tpp < tmax; tpp++) { |
| 693 | target = *tpp; |
| 694 | |
| 695 | /* |
| 696 | * Easy case: search for the LWP on the sleep queue. If |
| 697 | * it's parked, remove it from the queue and set running. |
| 698 | */ |
| 699 | TAILQ_FOREACH(t, sq, l_sleepchain) |
| 700 | if (t->l_proc == p && t->l_lid == target) |
| 701 | break; |
| 702 | |
| 703 | if (t != NULL) { |
| 704 | sleepq_remove(sq, t); |
| 705 | continue; |
| 706 | } |
| 707 | |
| 708 | /* |
| 709 | * The LWP hasn't parked yet. Take the hit and |
| 710 | * mark the operation as pending. |
| 711 | */ |
| 712 | mutex_spin_exit(mp); |
| 713 | mutex_enter(p->p_lock); |
| 714 | if ((t = lwp_find(p, target)) == NULL) { |
| 715 | mutex_exit(p->p_lock); |
| 716 | mutex_spin_enter(mp); |
| 717 | continue; |
| 718 | } |
| 719 | lwp_lock(t); |
| 720 | |
| 721 | /* |
| 722 | * It may not have parked yet, we may have raced, or |
| 723 | * it is parked on a different user sync object. |
| 724 | */ |
| 725 | if (t->l_syncobj == &lwp_park_sobj) { |
| 726 | /* Releases the LWP lock. */ |
| 727 | lwp_unsleep(t, true); |
| 728 | } else { |
| 729 | /* |
| 730 | * Set the operation pending. The next call to |
| 731 | * _lwp_park will return early. |
| 732 | */ |
| 733 | t->l_flag |= LW_UNPARKED; |
| 734 | lwp_unlock(t); |
| 735 | } |
| 736 | |
| 737 | mutex_exit(p->p_lock); |
| 738 | mutex_spin_enter(mp); |
| 739 | } |
| 740 | |
| 741 | mutex_spin_exit(mp); |
| 742 | if (tp != targets) |
| 743 | kmem_free(tp, sz); |
| 744 | |
| 745 | return 0; |
| 746 | } |
| 747 | |
| 748 | int |
| 749 | sys__lwp_setname(struct lwp *l, const struct sys__lwp_setname_args *uap, |
| 750 | register_t *retval) |
| 751 | { |
| 752 | /* { |
| 753 | syscallarg(lwpid_t) target; |
| 754 | syscallarg(const char *) name; |
| 755 | } */ |
| 756 | char *name, *oname; |
| 757 | lwpid_t target; |
| 758 | proc_t *p; |
| 759 | lwp_t *t; |
| 760 | int error; |
| 761 | |
| 762 | if ((target = SCARG(uap, target)) == 0) |
| 763 | target = l->l_lid; |
| 764 | |
| 765 | name = kmem_alloc(MAXCOMLEN, KM_SLEEP); |
| 766 | if (name == NULL) |
| 767 | return ENOMEM; |
| 768 | error = copyinstr(SCARG(uap, name), name, MAXCOMLEN, NULL); |
| 769 | switch (error) { |
| 770 | case ENAMETOOLONG: |
| 771 | case 0: |
| 772 | name[MAXCOMLEN - 1] = '\0'; |
| 773 | break; |
| 774 | default: |
| 775 | kmem_free(name, MAXCOMLEN); |
| 776 | return error; |
| 777 | } |
| 778 | |
| 779 | p = curproc; |
| 780 | mutex_enter(p->p_lock); |
| 781 | if ((t = lwp_find(p, target)) == NULL) { |
| 782 | mutex_exit(p->p_lock); |
| 783 | kmem_free(name, MAXCOMLEN); |
| 784 | return ESRCH; |
| 785 | } |
| 786 | lwp_lock(t); |
| 787 | oname = t->l_name; |
| 788 | t->l_name = name; |
| 789 | lwp_unlock(t); |
| 790 | mutex_exit(p->p_lock); |
| 791 | |
| 792 | if (oname != NULL) |
| 793 | kmem_free(oname, MAXCOMLEN); |
| 794 | |
| 795 | return 0; |
| 796 | } |
| 797 | |
| 798 | int |
| 799 | sys__lwp_getname(struct lwp *l, const struct sys__lwp_getname_args *uap, |
| 800 | register_t *retval) |
| 801 | { |
| 802 | /* { |
| 803 | syscallarg(lwpid_t) target; |
| 804 | syscallarg(char *) name; |
| 805 | syscallarg(size_t) len; |
| 806 | } */ |
| 807 | char name[MAXCOMLEN]; |
| 808 | lwpid_t target; |
| 809 | proc_t *p; |
| 810 | lwp_t *t; |
| 811 | |
| 812 | if ((target = SCARG(uap, target)) == 0) |
| 813 | target = l->l_lid; |
| 814 | |
| 815 | p = curproc; |
| 816 | mutex_enter(p->p_lock); |
| 817 | if ((t = lwp_find(p, target)) == NULL) { |
| 818 | mutex_exit(p->p_lock); |
| 819 | return ESRCH; |
| 820 | } |
| 821 | lwp_lock(t); |
| 822 | if (t->l_name == NULL) |
| 823 | name[0] = '\0'; |
| 824 | else |
| 825 | strcpy(name, t->l_name); |
| 826 | lwp_unlock(t); |
| 827 | mutex_exit(p->p_lock); |
| 828 | |
| 829 | return copyoutstr(name, SCARG(uap, name), SCARG(uap, len), NULL); |
| 830 | } |
| 831 | |
| 832 | int |
| 833 | sys__lwp_ctl(struct lwp *l, const struct sys__lwp_ctl_args *uap, |
| 834 | register_t *retval) |
| 835 | { |
| 836 | /* { |
| 837 | syscallarg(int) features; |
| 838 | syscallarg(struct lwpctl **) address; |
| 839 | } */ |
| 840 | int error, features; |
| 841 | vaddr_t vaddr; |
| 842 | |
| 843 | features = SCARG(uap, features); |
| 844 | features &= ~(LWPCTL_FEATURE_CURCPU | LWPCTL_FEATURE_PCTR); |
| 845 | if (features != 0) |
| 846 | return ENODEV; |
| 847 | if ((error = lwp_ctl_alloc(&vaddr)) != 0) |
| 848 | return error; |
| 849 | return copyout(&vaddr, SCARG(uap, address), sizeof(void *)); |
| 850 | } |
| 851 | |