1 /* $NetBSD: kern_timeout.c,v 1.28 2007/11/06 00:42:43 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 2003, 2006, 2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe, and by 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * Copyright (c) 2001 Thomas Nordin <nordin@openbsd.org> 41 * Copyright (c) 2000-2001 Artur Grabowski <art@openbsd.org> 42 * All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 48 * 1. Redistributions of source code must retain the above copyright 49 * notice, this list of conditions and the following disclaimer. 50 * 2. Redistributions in binary form must reproduce the above copyright 51 * notice, this list of conditions and the following disclaimer in the 52 * documentation and/or other materials provided with the distribution. 53 * 3. The name of the author may not be used to endorse or promote products 54 * derived from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 57 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 58 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 59 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 60 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 61 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 62 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 63 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 64 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 65 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 66 */ 67 68 #include <sys/cdefs.h> 69 __KERNEL_RCSID(0, "$NetBSD: kern_timeout.c,v 1.28 2007/11/06 00:42:43 ad Exp $"); 70 71 /* 72 * Timeouts are kept in a hierarchical timing wheel. The c_time is the 73 * value of the global variable "hardclock_ticks" when the timeout should 74 * be called. There are four levels with 256 buckets each. See 'Scheme 7' 75 * in "Hashed and Hierarchical Timing Wheels: Efficient Data Structures 76 * for Implementing a Timer Facility" by George Varghese and Tony Lauck. 77 * 78 * Some of the "math" in here is a bit tricky. We have to beware of 79 * wrapping ints. 80 * 81 * We use the fact that any element added to the queue must be added with 82 * a positive time. That means that any element `to' on the queue cannot 83 * be scheduled to timeout further in time than INT_MAX, but c->c_time can 84 * be positive or negative so comparing it with anything is dangerous. 85 * The only way we can use the c->c_time value in any predictable way is 86 * when we calculate how far in the future `to' will timeout - "c->c_time 87 * - hardclock_ticks". The result will always be positive for future 88 * timeouts and 0 or negative for due timeouts. 89 */ 90 91 #define _CALLOUT_PRIVATE 92 93 #include <sys/param.h> 94 #include <sys/systm.h> 95 #include <sys/kernel.h> 96 #include <sys/lock.h> 97 #include <sys/callout.h> 98 #include <sys/mutex.h> 99 #include <sys/proc.h> 100 #include <sys/sleepq.h> 101 #include <sys/syncobj.h> 102 #include <sys/evcnt.h> 103 #include <sys/intr.h> 104 105 #ifdef DDB 106 #include <machine/db_machdep.h> 107 #include <ddb/db_interface.h> 108 #include <ddb/db_access.h> 109 #include <ddb/db_sym.h> 110 #include <ddb/db_output.h> 111 #endif 112 113 #define BUCKETS 1024 114 #define WHEELSIZE 256 115 #define WHEELMASK 255 116 #define WHEELBITS 8 117 118 static struct callout_circq timeout_wheel[BUCKETS]; /* Queues of timeouts */ 119 static struct callout_circq timeout_todo; /* Worklist */ 120 121 #define MASKWHEEL(wheel, time) (((time) >> ((wheel)*WHEELBITS)) & WHEELMASK) 122 123 #define BUCKET(rel, abs) \ 124 (((rel) <= (1 << (2*WHEELBITS))) \ 125 ? ((rel) <= (1 << WHEELBITS)) \ 126 ? &timeout_wheel[MASKWHEEL(0, (abs))] \ 127 : &timeout_wheel[MASKWHEEL(1, (abs)) + WHEELSIZE] \ 128 : ((rel) <= (1 << (3*WHEELBITS))) \ 129 ? &timeout_wheel[MASKWHEEL(2, (abs)) + 2*WHEELSIZE] \ 130 : &timeout_wheel[MASKWHEEL(3, (abs)) + 3*WHEELSIZE]) 131 132 #define MOVEBUCKET(wheel, time) \ 133 CIRCQ_APPEND(&timeout_todo, \ 134 &timeout_wheel[MASKWHEEL((wheel), (time)) + (wheel)*WHEELSIZE]) 135 136 /* 137 * Circular queue definitions. 138 */ 139 140 #define CIRCQ_INIT(list) \ 141 do { \ 142 (list)->cq_next_l = (list); \ 143 (list)->cq_prev_l = (list); \ 144 } while (/*CONSTCOND*/0) 145 146 #define CIRCQ_INSERT(elem, list) \ 147 do { \ 148 (elem)->cq_prev_e = (list)->cq_prev_e; \ 149 (elem)->cq_next_l = (list); \ 150 (list)->cq_prev_l->cq_next_l = (elem); \ 151 (list)->cq_prev_l = (elem); \ 152 } while (/*CONSTCOND*/0) 153 154 #define CIRCQ_APPEND(fst, snd) \ 155 do { \ 156 if (!CIRCQ_EMPTY(snd)) { \ 157 (fst)->cq_prev_l->cq_next_l = (snd)->cq_next_l; \ 158 (snd)->cq_next_l->cq_prev_l = (fst)->cq_prev_l; \ 159 (snd)->cq_prev_l->cq_next_l = (fst); \ 160 (fst)->cq_prev_l = (snd)->cq_prev_l; \ 161 CIRCQ_INIT(snd); \ 162 } \ 163 } while (/*CONSTCOND*/0) 164 165 #define CIRCQ_REMOVE(elem) \ 166 do { \ 167 (elem)->cq_next_l->cq_prev_e = (elem)->cq_prev_e; \ 168 (elem)->cq_prev_l->cq_next_e = (elem)->cq_next_e; \ 169 } while (/*CONSTCOND*/0) 170 171 #define CIRCQ_FIRST(list) ((list)->cq_next_e) 172 #define CIRCQ_NEXT(elem) ((elem)->cq_next_e) 173 #define CIRCQ_LAST(elem,list) ((elem)->cq_next_l == (list)) 174 #define CIRCQ_EMPTY(list) ((list)->cq_next_l == (list)) 175 176 static void callout_softclock(void *); 177 178 /* 179 * All wheels are locked with the same lock (which must also block out 180 * all interrupts). Eventually this should become per-CPU. 181 */ 182 kmutex_t callout_lock; 183 sleepq_t callout_sleepq; 184 void *callout_si; 185 186 static struct evcnt callout_ev_late; 187 static struct evcnt callout_ev_block; 188 189 /* 190 * callout_barrier: 191 * 192 * If the callout is already running, wait until it completes. 193 * XXX This should do priority inheritance. 194 */ 195 static void 196 callout_barrier(callout_impl_t *c) 197 { 198 extern syncobj_t sleep_syncobj; 199 struct cpu_info *ci; 200 struct lwp *l; 201 202 l = curlwp; 203 204 if ((c->c_flags & CALLOUT_MPSAFE) == 0) { 205 /* 206 * Note: we must be called with the kernel lock held, 207 * as we use it to synchronize with callout_softclock(). 208 */ 209 ci = c->c_oncpu; 210 ci->ci_data.cpu_callout_cancel = c; 211 return; 212 } 213 214 while ((ci = c->c_oncpu) != NULL && ci->ci_data.cpu_callout == c) { 215 KASSERT(l->l_wchan == NULL); 216 217 ci->ci_data.cpu_callout_nwait++; 218 callout_ev_block.ev_count++; 219 220 l->l_kpriority = true; 221 sleepq_enter(&callout_sleepq, l); 222 sleepq_enqueue(&callout_sleepq, ci, "callout", &sleep_syncobj); 223 sleepq_block(0, false); 224 mutex_spin_enter(&callout_lock); 225 } 226 } 227 228 /* 229 * callout_running: 230 * 231 * Return non-zero if callout 'c' is currently executing. 232 */ 233 static inline bool 234 callout_running(callout_impl_t *c) 235 { 236 struct cpu_info *ci; 237 238 if ((ci = c->c_oncpu) == NULL) 239 return false; 240 if (ci->ci_data.cpu_callout != c) 241 return false; 242 if (c->c_onlwp == curlwp) 243 return false; 244 return true; 245 } 246 247 /* 248 * callout_startup: 249 * 250 * Initialize the callout facility, called at system startup time. 251 */ 252 void 253 callout_startup(void) 254 { 255 int b; 256 257 KASSERT(sizeof(callout_impl_t) <= sizeof(callout_t)); 258 259 CIRCQ_INIT(&timeout_todo); 260 for (b = 0; b < BUCKETS; b++) 261 CIRCQ_INIT(&timeout_wheel[b]); 262 263 mutex_init(&callout_lock, MUTEX_SPIN, IPL_SCHED); 264 sleepq_init(&callout_sleepq, &callout_lock); 265 266 evcnt_attach_dynamic(&callout_ev_late, EVCNT_TYPE_MISC, 267 NULL, "callout", "late"); 268 evcnt_attach_dynamic(&callout_ev_block, EVCNT_TYPE_MISC, 269 NULL, "callout", "block waiting"); 270 } 271 272 /* 273 * callout_startup2: 274 * 275 * Complete initialization once soft interrupts are available. 276 */ 277 void 278 callout_startup2(void) 279 { 280 281 callout_si = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE, 282 callout_softclock, NULL); 283 if (callout_si == NULL) 284 panic("callout_startup2: unable to register softclock intr"); 285 } 286 287 /* 288 * callout_init: 289 * 290 * Initialize a callout structure. 291 */ 292 void 293 callout_init(callout_t *cs, u_int flags) 294 { 295 callout_impl_t *c = (callout_impl_t *)cs; 296 297 KASSERT((flags & ~CALLOUT_FLAGMASK) == 0); 298 299 memset(c, 0, sizeof(*c)); 300 c->c_flags = flags; 301 c->c_magic = CALLOUT_MAGIC; 302 } 303 304 /* 305 * callout_destroy: 306 * 307 * Destroy a callout structure. The callout must be stopped. 308 */ 309 void 310 callout_destroy(callout_t *cs) 311 { 312 callout_impl_t *c = (callout_impl_t *)cs; 313 314 /* 315 * It's not necessary to lock in order to see the correct value 316 * of c->c_flags. If the callout could potentially have been 317 * running, the current thread should have stopped it. 318 */ 319 KASSERT((c->c_flags & CALLOUT_PENDING) == 0); 320 if (c->c_oncpu != NULL) { 321 KASSERT( 322 ((struct cpu_info *)c->c_oncpu)->ci_data.cpu_callout != c); 323 } 324 KASSERT(c->c_magic == CALLOUT_MAGIC); 325 326 c->c_magic = 0; 327 } 328 329 330 /* 331 * callout_reset: 332 * 333 * Reset a callout structure with a new function and argument, and 334 * schedule it to run. 335 */ 336 void 337 callout_reset(callout_t *cs, int to_ticks, void (*func)(void *), void *arg) 338 { 339 callout_impl_t *c = (callout_impl_t *)cs; 340 int old_time; 341 342 KASSERT(to_ticks >= 0); 343 KASSERT(c->c_magic == CALLOUT_MAGIC); 344 KASSERT(func != NULL); 345 346 mutex_spin_enter(&callout_lock); 347 348 /* Initialize the time here, it won't change. */ 349 old_time = c->c_time; 350 c->c_time = to_ticks + hardclock_ticks; 351 c->c_flags &= ~CALLOUT_FIRED; 352 353 c->c_func = func; 354 c->c_arg = arg; 355 356 /* 357 * If this timeout is already scheduled and now is moved 358 * earlier, reschedule it now. Otherwise leave it in place 359 * and let it be rescheduled later. 360 */ 361 if ((c->c_flags & CALLOUT_PENDING) != 0) { 362 if (c->c_time - old_time < 0) { 363 CIRCQ_REMOVE(&c->c_list); 364 CIRCQ_INSERT(&c->c_list, &timeout_todo); 365 } 366 } else { 367 c->c_flags |= CALLOUT_PENDING; 368 CIRCQ_INSERT(&c->c_list, &timeout_todo); 369 } 370 371 mutex_spin_exit(&callout_lock); 372 } 373 374 /* 375 * callout_schedule: 376 * 377 * Schedule a callout to run. The function and argument must 378 * already be set in the callout structure. 379 */ 380 void 381 callout_schedule(callout_t *cs, int to_ticks) 382 { 383 callout_impl_t *c = (callout_impl_t *)cs; 384 int old_time; 385 386 KASSERT(to_ticks >= 0); 387 KASSERT(c->c_magic == CALLOUT_MAGIC); 388 KASSERT(c->c_func != NULL); 389 390 mutex_spin_enter(&callout_lock); 391 392 /* Initialize the time here, it won't change. */ 393 old_time = c->c_time; 394 c->c_time = to_ticks + hardclock_ticks; 395 c->c_flags &= ~CALLOUT_FIRED; 396 397 /* 398 * If this timeout is already scheduled and now is moved 399 * earlier, reschedule it now. Otherwise leave it in place 400 * and let it be rescheduled later. 401 */ 402 if ((c->c_flags & CALLOUT_PENDING) != 0) { 403 if (c->c_time - old_time < 0) { 404 CIRCQ_REMOVE(&c->c_list); 405 CIRCQ_INSERT(&c->c_list, &timeout_todo); 406 } 407 } else { 408 c->c_flags |= CALLOUT_PENDING; 409 CIRCQ_INSERT(&c->c_list, &timeout_todo); 410 } 411 412 mutex_spin_exit(&callout_lock); 413 } 414 415 /* 416 * callout_stop: 417 * 418 * Cancel a pending callout. 419 */ 420 bool 421 callout_stop(callout_t *cs) 422 { 423 callout_impl_t *c = (callout_impl_t *)cs; 424 bool expired; 425 426 KASSERT(c->c_magic == CALLOUT_MAGIC); 427 428 mutex_spin_enter(&callout_lock); 429 430 if (callout_running(c)) 431 callout_barrier(c); 432 433 if ((c->c_flags & CALLOUT_PENDING) != 0) 434 CIRCQ_REMOVE(&c->c_list); 435 436 expired = ((c->c_flags & CALLOUT_FIRED) != 0); 437 c->c_flags &= ~(CALLOUT_PENDING|CALLOUT_FIRED); 438 439 mutex_spin_exit(&callout_lock); 440 441 return expired; 442 } 443 444 void 445 callout_setfunc(callout_t *cs, void (*func)(void *), void *arg) 446 { 447 callout_impl_t *c = (callout_impl_t *)cs; 448 449 KASSERT(c->c_magic == CALLOUT_MAGIC); 450 451 mutex_spin_enter(&callout_lock); 452 c->c_func = func; 453 c->c_arg = arg; 454 mutex_spin_exit(&callout_lock); 455 } 456 457 bool 458 callout_expired(callout_t *cs) 459 { 460 callout_impl_t *c = (callout_impl_t *)cs; 461 bool rv; 462 463 KASSERT(c->c_magic == CALLOUT_MAGIC); 464 465 mutex_spin_enter(&callout_lock); 466 rv = ((c->c_flags & CALLOUT_FIRED) != 0); 467 mutex_spin_exit(&callout_lock); 468 469 return rv; 470 } 471 472 bool 473 callout_active(callout_t *cs) 474 { 475 callout_impl_t *c = (callout_impl_t *)cs; 476 bool rv; 477 478 KASSERT(c->c_magic == CALLOUT_MAGIC); 479 480 mutex_spin_enter(&callout_lock); 481 rv = ((c->c_flags & (CALLOUT_PENDING|CALLOUT_FIRED)) != 0); 482 mutex_spin_exit(&callout_lock); 483 484 return rv; 485 } 486 487 bool 488 callout_pending(callout_t *cs) 489 { 490 callout_impl_t *c = (callout_impl_t *)cs; 491 bool rv; 492 493 KASSERT(c->c_magic == CALLOUT_MAGIC); 494 495 mutex_spin_enter(&callout_lock); 496 rv = ((c->c_flags & CALLOUT_PENDING) != 0); 497 mutex_spin_exit(&callout_lock); 498 499 return rv; 500 } 501 502 bool 503 callout_invoking(callout_t *cs) 504 { 505 callout_impl_t *c = (callout_impl_t *)cs; 506 bool rv; 507 508 KASSERT(c->c_magic == CALLOUT_MAGIC); 509 510 mutex_spin_enter(&callout_lock); 511 rv = ((c->c_flags & CALLOUT_INVOKING) != 0); 512 mutex_spin_exit(&callout_lock); 513 514 return rv; 515 } 516 517 void 518 callout_ack(callout_t *cs) 519 { 520 callout_impl_t *c = (callout_impl_t *)cs; 521 522 KASSERT(c->c_magic == CALLOUT_MAGIC); 523 524 mutex_spin_enter(&callout_lock); 525 c->c_flags &= ~CALLOUT_INVOKING; 526 mutex_spin_exit(&callout_lock); 527 } 528 529 /* 530 * This is called from hardclock() once every tick. 531 * We schedule callout_softclock() if there is work 532 * to be done. 533 */ 534 void 535 callout_hardclock(void) 536 { 537 int needsoftclock; 538 539 mutex_spin_enter(&callout_lock); 540 541 MOVEBUCKET(0, hardclock_ticks); 542 if (MASKWHEEL(0, hardclock_ticks) == 0) { 543 MOVEBUCKET(1, hardclock_ticks); 544 if (MASKWHEEL(1, hardclock_ticks) == 0) { 545 MOVEBUCKET(2, hardclock_ticks); 546 if (MASKWHEEL(2, hardclock_ticks) == 0) 547 MOVEBUCKET(3, hardclock_ticks); 548 } 549 } 550 551 needsoftclock = !CIRCQ_EMPTY(&timeout_todo); 552 mutex_spin_exit(&callout_lock); 553 554 if (needsoftclock) 555 softint_schedule(callout_si); 556 } 557 558 /* ARGSUSED */ 559 static void 560 callout_softclock(void *v) 561 { 562 callout_impl_t *c; 563 struct cpu_info *ci; 564 void (*func)(void *); 565 void *arg; 566 u_int mpsafe, count; 567 lwp_t *l; 568 569 l = curlwp; 570 ci = l->l_cpu; 571 572 mutex_spin_enter(&callout_lock); 573 574 while (!CIRCQ_EMPTY(&timeout_todo)) { 575 c = CIRCQ_FIRST(&timeout_todo); 576 KASSERT(c->c_magic == CALLOUT_MAGIC); 577 KASSERT(c->c_func != NULL); 578 KASSERT((c->c_flags & CALLOUT_PENDING) != 0); 579 KASSERT((c->c_flags & CALLOUT_FIRED) == 0); 580 CIRCQ_REMOVE(&c->c_list); 581 582 /* If due run it, otherwise insert it into the right bucket. */ 583 if (c->c_time - hardclock_ticks > 0) { 584 CIRCQ_INSERT(&c->c_list, 585 BUCKET((c->c_time - hardclock_ticks), c->c_time)); 586 } else { 587 if (c->c_time - hardclock_ticks < 0) 588 callout_ev_late.ev_count++; 589 590 c->c_flags ^= (CALLOUT_PENDING | CALLOUT_FIRED); 591 mpsafe = (c->c_flags & CALLOUT_MPSAFE); 592 func = c->c_func; 593 arg = c->c_arg; 594 c->c_oncpu = ci; 595 c->c_onlwp = l; 596 597 mutex_spin_exit(&callout_lock); 598 if (!mpsafe) { 599 KERNEL_LOCK(1, curlwp); 600 if (ci->ci_data.cpu_callout_cancel != c) 601 (*func)(arg); 602 KERNEL_UNLOCK_ONE(curlwp); 603 } else 604 (*func)(arg); 605 mutex_spin_enter(&callout_lock); 606 607 /* 608 * We can't touch 'c' here because it might be 609 * freed already. If LWPs waiting for callout 610 * to complete, awaken them. 611 */ 612 ci->ci_data.cpu_callout_cancel = NULL; 613 ci->ci_data.cpu_callout = NULL; 614 if ((count = ci->ci_data.cpu_callout_nwait) != 0) { 615 ci->ci_data.cpu_callout_nwait = 0; 616 /* sleepq_wake() drops the lock. */ 617 sleepq_wake(&callout_sleepq, ci, count); 618 mutex_spin_enter(&callout_lock); 619 } 620 } 621 } 622 623 mutex_spin_exit(&callout_lock); 624 } 625 626 #ifdef DDB 627 static void 628 db_show_callout_bucket(struct callout_circq *bucket) 629 { 630 callout_impl_t *c; 631 db_expr_t offset; 632 const char *name; 633 static char question[] = "?"; 634 635 if (CIRCQ_EMPTY(bucket)) 636 return; 637 638 for (c = CIRCQ_FIRST(bucket); /*nothing*/; c = CIRCQ_NEXT(&c->c_list)) { 639 db_find_sym_and_offset((db_addr_t)(intptr_t)c->c_func, &name, 640 &offset); 641 name = name ? name : question; 642 #ifdef _LP64 643 #define POINTER_WIDTH "%16lx" 644 #else 645 #define POINTER_WIDTH "%8lx" 646 #endif 647 db_printf("%9d %2d/%-4d " POINTER_WIDTH " %s\n", 648 c->c_time - hardclock_ticks, 649 (int)((bucket - timeout_wheel) / WHEELSIZE), 650 (int)(bucket - timeout_wheel), (u_long) c->c_arg, name); 651 652 if (CIRCQ_LAST(&c->c_list, bucket)) 653 break; 654 } 655 } 656 657 void 658 db_show_callout(db_expr_t addr, bool haddr, db_expr_t count, const char *modif) 659 { 660 int b; 661 662 db_printf("hardclock_ticks now: %d\n", hardclock_ticks); 663 #ifdef _LP64 664 db_printf(" ticks wheel arg func\n"); 665 #else 666 db_printf(" ticks wheel arg func\n"); 667 #endif 668 669 /* 670 * Don't lock the callwheel; all the other CPUs are paused 671 * anyhow, and we might be called in a circumstance where 672 * some other CPU was paused while holding the lock. 673 */ 674 675 db_show_callout_bucket(&timeout_todo); 676 for (b = 0; b < BUCKETS; b++) 677 db_show_callout_bucket(&timeout_wheel[b]); 678 } 679 #endif /* DDB */ 680