kern_thr.c revision 184667
1/*- 2 * Copyright (c) 2003, Jeffrey Roberson <jeff@freebsd.org> 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 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/kern/kern_thr.c 184667 2008-11-05 03:01:23Z davidxu $"); 29 30#include "opt_compat.h" 31#include "opt_posix.h" 32#include <sys/param.h> 33#include <sys/kernel.h> 34#include <sys/lock.h> 35#include <sys/mutex.h> 36#include <sys/priv.h> 37#include <sys/proc.h> 38#include <sys/posix4.h> 39#include <sys/resourcevar.h> 40#include <sys/sched.h> 41#include <sys/sysctl.h> 42#include <sys/smp.h> 43#include <sys/syscallsubr.h> 44#include <sys/sysent.h> 45#include <sys/systm.h> 46#include <sys/sysproto.h> 47#include <sys/signalvar.h> 48#include <sys/ucontext.h> 49#include <sys/thr.h> 50#include <sys/rtprio.h> 51#include <sys/umtx.h> 52#include <sys/limits.h> 53 54#include <machine/frame.h> 55 56#include <security/audit/audit.h> 57 58#ifdef COMPAT_IA32 59 60extern struct sysentvec ia32_freebsd_sysvec; 61 62static inline int 63suword_lwpid(void *addr, lwpid_t lwpid) 64{ 65 int error; 66 67 if (curproc->p_sysent != &ia32_freebsd_sysvec) 68 error = suword(addr, lwpid); 69 else 70 error = suword32(addr, lwpid); 71 return (error); 72} 73 74#else 75#define suword_lwpid suword 76#endif 77 78extern int max_threads_per_proc; 79extern int max_threads_hits; 80 81static int create_thread(struct thread *td, mcontext_t *ctx, 82 void (*start_func)(void *), void *arg, 83 char *stack_base, size_t stack_size, 84 char *tls_base, 85 long *child_tid, long *parent_tid, 86 int flags, struct rtprio *rtp); 87 88/* 89 * System call interface. 90 */ 91int 92thr_create(struct thread *td, struct thr_create_args *uap) 93 /* ucontext_t *ctx, long *id, int flags */ 94{ 95 ucontext_t ctx; 96 int error; 97 98 if ((error = copyin(uap->ctx, &ctx, sizeof(ctx)))) 99 return (error); 100 101 error = create_thread(td, &ctx.uc_mcontext, NULL, NULL, 102 NULL, 0, NULL, uap->id, NULL, uap->flags, NULL); 103 return (error); 104} 105 106int 107thr_new(struct thread *td, struct thr_new_args *uap) 108 /* struct thr_param * */ 109{ 110 struct thr_param param; 111 int error; 112 113 if (uap->param_size < 0 || uap->param_size > sizeof(param)) 114 return (EINVAL); 115 bzero(¶m, sizeof(param)); 116 if ((error = copyin(uap->param, ¶m, uap->param_size))) 117 return (error); 118 return (kern_thr_new(td, ¶m)); 119} 120 121int 122kern_thr_new(struct thread *td, struct thr_param *param) 123{ 124 struct rtprio rtp, *rtpp; 125 int error; 126 127 rtpp = NULL; 128 if (param->rtp != 0) { 129 error = copyin(param->rtp, &rtp, sizeof(struct rtprio)); 130 if (error) 131 return (error); 132 rtpp = &rtp; 133 } 134 error = create_thread(td, NULL, param->start_func, param->arg, 135 param->stack_base, param->stack_size, param->tls_base, 136 param->child_tid, param->parent_tid, param->flags, 137 rtpp); 138 return (error); 139} 140 141static int 142create_thread(struct thread *td, mcontext_t *ctx, 143 void (*start_func)(void *), void *arg, 144 char *stack_base, size_t stack_size, 145 char *tls_base, 146 long *child_tid, long *parent_tid, 147 int flags, struct rtprio *rtp) 148{ 149 stack_t stack; 150 struct thread *newtd; 151 struct proc *p; 152 int error; 153 154 error = 0; 155 p = td->td_proc; 156 157 /* Have race condition but it is cheap. */ 158 if (p->p_numthreads >= max_threads_per_proc) { 159 ++max_threads_hits; 160 return (EPROCLIM); 161 } 162 163 if (rtp != NULL) { 164 switch(rtp->type) { 165 case RTP_PRIO_REALTIME: 166 case RTP_PRIO_FIFO: 167 /* Only root can set scheduler policy */ 168 if (priv_check(td, PRIV_SCHED_SETPOLICY) != 0) 169 return (EPERM); 170 if (rtp->prio > RTP_PRIO_MAX) 171 return (EINVAL); 172 break; 173 case RTP_PRIO_NORMAL: 174 rtp->prio = 0; 175 break; 176 default: 177 return (EINVAL); 178 } 179 } 180 181 /* Initialize our td */ 182 newtd = thread_alloc(); 183 if (newtd == NULL) 184 return (ENOMEM); 185 186 /* 187 * Try the copyout as soon as we allocate the td so we don't 188 * have to tear things down in a failure case below. 189 * Here we copy out tid to two places, one for child and one 190 * for parent, because pthread can create a detached thread, 191 * if parent wants to safely access child tid, it has to provide 192 * its storage, because child thread may exit quickly and 193 * memory is freed before parent thread can access it. 194 */ 195 if ((child_tid != NULL && 196 suword_lwpid(child_tid, newtd->td_tid)) || 197 (parent_tid != NULL && 198 suword_lwpid(parent_tid, newtd->td_tid))) { 199 thread_free(newtd); 200 return (EFAULT); 201 } 202 203 bzero(&newtd->td_startzero, 204 __rangeof(struct thread, td_startzero, td_endzero)); 205 bcopy(&td->td_startcopy, &newtd->td_startcopy, 206 __rangeof(struct thread, td_startcopy, td_endcopy)); 207 newtd->td_proc = td->td_proc; 208 newtd->td_ucred = crhold(td->td_ucred); 209 210 cpu_set_upcall(newtd, td); 211 212 if (ctx != NULL) { /* old way to set user context */ 213 error = set_mcontext(newtd, ctx); 214 if (error != 0) { 215 thread_free(newtd); 216 crfree(td->td_ucred); 217 return (error); 218 } 219 } else { 220 /* Set up our machine context. */ 221 stack.ss_sp = stack_base; 222 stack.ss_size = stack_size; 223 /* Set upcall address to user thread entry function. */ 224 cpu_set_upcall_kse(newtd, start_func, arg, &stack); 225 /* Setup user TLS address and TLS pointer register. */ 226 error = cpu_set_user_tls(newtd, tls_base); 227 if (error != 0) { 228 thread_free(newtd); 229 crfree(td->td_ucred); 230 return (error); 231 } 232 } 233 234 PROC_LOCK(td->td_proc); 235 td->td_proc->p_flag |= P_HADTHREADS; 236 newtd->td_sigmask = td->td_sigmask; 237 thread_link(newtd, p); 238 bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name)); 239 thread_lock(td); 240 /* let the scheduler know about these things. */ 241 sched_fork_thread(td, newtd); 242 thread_unlock(td); 243 if (P_SHOULDSTOP(p)) 244 newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 245 PROC_UNLOCK(p); 246 thread_lock(newtd); 247 if (rtp != NULL) { 248 if (!(td->td_pri_class == PRI_TIMESHARE && 249 rtp->type == RTP_PRIO_NORMAL)) { 250 rtp_to_pri(rtp, newtd); 251 sched_prio(newtd, newtd->td_user_pri); 252 } /* ignore timesharing class */ 253 } 254 TD_SET_CAN_RUN(newtd); 255 sched_add(newtd, SRQ_BORING); 256 thread_unlock(newtd); 257 258 return (error); 259} 260 261int 262thr_self(struct thread *td, struct thr_self_args *uap) 263 /* long *id */ 264{ 265 int error; 266 267 error = suword_lwpid(uap->id, (unsigned)td->td_tid); 268 if (error == -1) 269 return (EFAULT); 270 return (0); 271} 272 273int 274thr_exit(struct thread *td, struct thr_exit_args *uap) 275 /* long *state */ 276{ 277 struct proc *p; 278 279 p = td->td_proc; 280 281 /* Signal userland that it can free the stack. */ 282 if ((void *)uap->state != NULL) { 283 suword_lwpid(uap->state, 1); 284 kern_umtx_wake(td, uap->state, INT_MAX, 0); 285 } 286 287 PROC_LOCK(p); 288 sigqueue_flush(&td->td_sigqueue); 289 PROC_SLOCK(p); 290 291 /* 292 * Shutting down last thread in the proc. This will actually 293 * call exit() in the trampoline when it returns. 294 */ 295 if (p->p_numthreads != 1) { 296 thread_stopped(p); 297 thread_exit(); 298 /* NOTREACHED */ 299 } 300 PROC_SUNLOCK(p); 301 PROC_UNLOCK(p); 302 return (0); 303} 304 305int 306thr_kill(struct thread *td, struct thr_kill_args *uap) 307 /* long id, int sig */ 308{ 309 struct thread *ttd; 310 struct proc *p; 311 int error; 312 313 p = td->td_proc; 314 error = 0; 315 PROC_LOCK(p); 316 if (uap->id == -1) { 317 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 318 error = EINVAL; 319 } else { 320 error = ESRCH; 321 FOREACH_THREAD_IN_PROC(p, ttd) { 322 if (ttd != td) { 323 error = 0; 324 if (uap->sig == 0) 325 break; 326 tdsignal(p, ttd, uap->sig, NULL); 327 } 328 } 329 } 330 } else { 331 if (uap->id != td->td_tid) 332 ttd = thread_find(p, uap->id); 333 else 334 ttd = td; 335 if (ttd == NULL) 336 error = ESRCH; 337 else if (uap->sig == 0) 338 ; 339 else if (!_SIG_VALID(uap->sig)) 340 error = EINVAL; 341 else 342 tdsignal(p, ttd, uap->sig, NULL); 343 } 344 PROC_UNLOCK(p); 345 return (error); 346} 347 348int 349thr_kill2(struct thread *td, struct thr_kill2_args *uap) 350 /* pid_t pid, long id, int sig */ 351{ 352 struct thread *ttd; 353 struct proc *p; 354 int error; 355 356 AUDIT_ARG(signum, uap->sig); 357 358 if (uap->pid == td->td_proc->p_pid) { 359 p = td->td_proc; 360 PROC_LOCK(p); 361 } else if ((p = pfind(uap->pid)) == NULL) { 362 return (ESRCH); 363 } 364 AUDIT_ARG(process, p); 365 366 error = p_cansignal(td, p, uap->sig); 367 if (error == 0) { 368 if (uap->id == -1) { 369 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 370 error = EINVAL; 371 } else { 372 error = ESRCH; 373 FOREACH_THREAD_IN_PROC(p, ttd) { 374 if (ttd != td) { 375 error = 0; 376 if (uap->sig == 0) 377 break; 378 tdsignal(p, ttd, uap->sig, NULL); 379 } 380 } 381 } 382 } else { 383 if (uap->id != td->td_tid) 384 ttd = thread_find(p, uap->id); 385 else 386 ttd = td; 387 if (ttd == NULL) 388 error = ESRCH; 389 else if (uap->sig == 0) 390 ; 391 else if (!_SIG_VALID(uap->sig)) 392 error = EINVAL; 393 else 394 tdsignal(p, ttd, uap->sig, NULL); 395 } 396 } 397 PROC_UNLOCK(p); 398 return (error); 399} 400 401int 402thr_suspend(struct thread *td, struct thr_suspend_args *uap) 403 /* const struct timespec *timeout */ 404{ 405 struct timespec ts, *tsp; 406 int error; 407 408 error = 0; 409 tsp = NULL; 410 if (uap->timeout != NULL) { 411 error = copyin((const void *)uap->timeout, (void *)&ts, 412 sizeof(struct timespec)); 413 if (error != 0) 414 return (error); 415 tsp = &ts; 416 } 417 418 return (kern_thr_suspend(td, tsp)); 419} 420 421int 422kern_thr_suspend(struct thread *td, struct timespec *tsp) 423{ 424 struct timeval tv; 425 int error = 0, hz = 0; 426 427 if (tsp != NULL) { 428 if (tsp->tv_nsec < 0 || tsp->tv_nsec > 1000000000) 429 return (EINVAL); 430 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) 431 return (ETIMEDOUT); 432 TIMESPEC_TO_TIMEVAL(&tv, tsp); 433 hz = tvtohz(&tv); 434 } 435 436 if (td->td_pflags & TDP_WAKEUP) { 437 td->td_pflags &= ~TDP_WAKEUP; 438 return (0); 439 } 440 441 PROC_LOCK(td->td_proc); 442 if ((td->td_flags & TDF_THRWAKEUP) == 0) 443 error = msleep((void *)td, &td->td_proc->p_mtx, PCATCH, "lthr", 444 hz); 445 if (td->td_flags & TDF_THRWAKEUP) { 446 thread_lock(td); 447 td->td_flags &= ~TDF_THRWAKEUP; 448 thread_unlock(td); 449 PROC_UNLOCK(td->td_proc); 450 return (0); 451 } 452 PROC_UNLOCK(td->td_proc); 453 if (error == EWOULDBLOCK) 454 error = ETIMEDOUT; 455 else if (error == ERESTART) { 456 if (hz != 0) 457 error = EINTR; 458 } 459 return (error); 460} 461 462int 463thr_wake(struct thread *td, struct thr_wake_args *uap) 464 /* long id */ 465{ 466 struct proc *p; 467 struct thread *ttd; 468 469 if (uap->id == td->td_tid) { 470 td->td_pflags |= TDP_WAKEUP; 471 return (0); 472 } 473 474 p = td->td_proc; 475 PROC_LOCK(p); 476 ttd = thread_find(p, uap->id); 477 if (ttd == NULL) { 478 PROC_UNLOCK(p); 479 return (ESRCH); 480 } 481 thread_lock(ttd); 482 ttd->td_flags |= TDF_THRWAKEUP; 483 thread_unlock(ttd); 484 wakeup((void *)ttd); 485 PROC_UNLOCK(p); 486 return (0); 487} 488 489int 490thr_set_name(struct thread *td, struct thr_set_name_args *uap) 491{ 492 struct proc *p = td->td_proc; 493 char name[MAXCOMLEN + 1]; 494 struct thread *ttd; 495 int error; 496 497 error = 0; 498 name[0] = '\0'; 499 if (uap->name != NULL) { 500 error = copyinstr(uap->name, name, sizeof(name), 501 NULL); 502 if (error) 503 return (error); 504 } 505 PROC_LOCK(p); 506 if (uap->id == td->td_tid) 507 ttd = td; 508 else 509 ttd = thread_find(p, uap->id); 510 if (ttd != NULL) 511 strcpy(ttd->td_name, name); 512 else 513 error = ESRCH; 514 PROC_UNLOCK(p); 515 return (error); 516} 517