Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_intr.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1997, Stefan Esser <se@freebsd.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 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 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_ddb.h" 33 #include "opt_kstack_usage_prof.h" 34 35 #include <sys/param.h> 36 #include <sys/bus.h> 37 #include <sys/conf.h> 38 #include <sys/cpuset.h> 39 #include <sys/rtprio.h> 40 #include <sys/systm.h> 41 #include <sys/interrupt.h> 42 #include <sys/kernel.h> 43 #include <sys/kthread.h> 44 #include <sys/ktr.h> 45 #include <sys/limits.h> 46 #include <sys/lock.h> 47 #include <sys/malloc.h> 48 #include <sys/mutex.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/epoch.h> 52 #include <sys/random.h> 53 #include <sys/resourcevar.h> 54 #include <sys/sched.h> 55 #include <sys/smp.h> 56 #include <sys/sysctl.h> 57 #include <sys/syslog.h> 58 #include <sys/unistd.h> 59 #include <sys/vmmeter.h> 60 #include <machine/atomic.h> 61 #include <machine/cpu.h> 62 #include <machine/md_var.h> 63 #include <machine/smp.h> 64 #include <machine/stdarg.h> 65 #ifdef DDB 66 #include <ddb/ddb.h> 67 #include <ddb/db_sym.h> 68 #endif 69 70 /* 71 * Describe an interrupt thread. There is one of these per interrupt event. 72 */ 73 struct intr_thread { 74 struct intr_event *it_event; 75 struct thread *it_thread; /* Kernel thread. */ 76 int it_flags; /* (j) IT_* flags. */ 77 int it_need; /* Needs service. */ 78 }; 79 80 /* Interrupt thread flags kept in it_flags */ 81 #define IT_DEAD 0x000001 /* Thread is waiting to exit. */ 82 #define IT_WAIT 0x000002 /* Thread is waiting for completion. */ 83 84 struct intr_entropy { 85 struct thread *td; 86 uintptr_t event; 87 }; 88 89 struct intr_event *clk_intr_event; 90 struct proc *intrproc; 91 92 static MALLOC_DEFINE(M_ITHREAD, "ithread", "Interrupt Threads"); 93 94 static int intr_storm_threshold = 0; 95 SYSCTL_INT(_hw, OID_AUTO, intr_storm_threshold, CTLFLAG_RWTUN, 96 &intr_storm_threshold, 0, 97 "Number of consecutive interrupts before storm protection is enabled"); 98 static int intr_epoch_batch = 1000; 99 SYSCTL_INT(_hw, OID_AUTO, intr_epoch_batch, CTLFLAG_RWTUN, &intr_epoch_batch, 100 0, "Maximum interrupt handler executions without re-entering epoch(9)"); 101 static TAILQ_HEAD(, intr_event) event_list = 102 TAILQ_HEAD_INITIALIZER(event_list); 103 static struct mtx event_lock; 104 MTX_SYSINIT(intr_event_list, &event_lock, "intr event list", MTX_DEF); 105 106 static void intr_event_update(struct intr_event *ie); 107 static int intr_event_schedule_thread(struct intr_event *ie); 108 static struct intr_thread *ithread_create(const char *name); 109 static void ithread_destroy(struct intr_thread *ithread); 110 static void ithread_execute_handlers(struct proc *p, 111 struct intr_event *ie); 112 static void ithread_loop(void *); 113 static void ithread_update(struct intr_thread *ithd); 114 static void start_softintr(void *); 115 116 /* Map an interrupt type to an ithread priority. */ 117 u_char 118 intr_priority(enum intr_type flags) 119 { 120 u_char pri; 121 122 flags &= (INTR_TYPE_TTY | INTR_TYPE_BIO | INTR_TYPE_NET | 123 INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK | INTR_TYPE_AV); 124 switch (flags) { 125 case INTR_TYPE_TTY: 126 pri = PI_TTY; 127 break; 128 case INTR_TYPE_BIO: 129 pri = PI_DISK; 130 break; 131 case INTR_TYPE_NET: 132 pri = PI_NET; 133 break; 134 case INTR_TYPE_CAM: 135 pri = PI_DISK; 136 break; 137 case INTR_TYPE_AV: 138 pri = PI_AV; 139 break; 140 case INTR_TYPE_CLK: 141 pri = PI_REALTIME; 142 break; 143 case INTR_TYPE_MISC: 144 pri = PI_DULL; /* don't care */ 145 break; 146 default: 147 /* We didn't specify an interrupt level. */ 148 panic("intr_priority: no interrupt type in flags"); 149 } 150 151 return pri; 152 } 153 154 /* 155 * Update an ithread based on the associated intr_event. 156 */ 157 static void 158 ithread_update(struct intr_thread *ithd) 159 { 160 struct intr_event *ie; 161 struct thread *td; 162 u_char pri; 163 164 ie = ithd->it_event; 165 td = ithd->it_thread; 166 mtx_assert(&ie->ie_lock, MA_OWNED); 167 168 /* Determine the overall priority of this event. */ 169 if (CK_SLIST_EMPTY(&ie->ie_handlers)) 170 pri = PRI_MAX_ITHD; 171 else 172 pri = CK_SLIST_FIRST(&ie->ie_handlers)->ih_pri; 173 174 /* Update name and priority. */ 175 strlcpy(td->td_name, ie->ie_fullname, sizeof(td->td_name)); 176 #ifdef KTR 177 sched_clear_tdname(td); 178 #endif 179 thread_lock(td); 180 sched_prio(td, pri); 181 thread_unlock(td); 182 } 183 184 /* 185 * Regenerate the full name of an interrupt event and update its priority. 186 */ 187 static void 188 intr_event_update(struct intr_event *ie) 189 { 190 struct intr_handler *ih; 191 char *last; 192 int missed, space, flags; 193 194 /* Start off with no entropy and just the name of the event. */ 195 mtx_assert(&ie->ie_lock, MA_OWNED); 196 strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname)); 197 flags = 0; 198 missed = 0; 199 space = 1; 200 201 /* Run through all the handlers updating values. */ 202 CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) { 203 if (strlen(ie->ie_fullname) + strlen(ih->ih_name) + 1 < 204 sizeof(ie->ie_fullname)) { 205 strcat(ie->ie_fullname, " "); 206 strcat(ie->ie_fullname, ih->ih_name); 207 space = 0; 208 } else 209 missed++; 210 flags |= ih->ih_flags; 211 } 212 ie->ie_hflags = flags; 213 214 /* 215 * If there is only one handler and its name is too long, just copy in 216 * as much of the end of the name (includes the unit number) as will 217 * fit. Otherwise, we have multiple handlers and not all of the names 218 * will fit. Add +'s to indicate missing names. If we run out of room 219 * and still have +'s to add, change the last character from a + to a *. 220 */ 221 if (missed == 1 && space == 1) { 222 ih = CK_SLIST_FIRST(&ie->ie_handlers); 223 missed = strlen(ie->ie_fullname) + strlen(ih->ih_name) + 2 - 224 sizeof(ie->ie_fullname); 225 strcat(ie->ie_fullname, (missed == 0) ? " " : "-"); 226 strcat(ie->ie_fullname, &ih->ih_name[missed]); 227 missed = 0; 228 } 229 last = &ie->ie_fullname[sizeof(ie->ie_fullname) - 2]; 230 while (missed-- > 0) { 231 if (strlen(ie->ie_fullname) + 1 == sizeof(ie->ie_fullname)) { 232 if (*last == '+') { 233 *last = '*'; 234 break; 235 } else 236 *last = '+'; 237 } else if (space) { 238 strcat(ie->ie_fullname, " +"); 239 space = 0; 240 } else 241 strcat(ie->ie_fullname, "+"); 242 } 243 244 /* 245 * If this event has an ithread, update it's priority and 246 * name. 247 */ 248 if (ie->ie_thread != NULL) 249 ithread_update(ie->ie_thread); 250 CTR2(KTR_INTR, "%s: updated %s", __func__, ie->ie_fullname); 251 } 252 253 int 254 intr_event_create(struct intr_event **event, void *source, int flags, int irq, 255 void (*pre_ithread)(void *), void (*post_ithread)(void *), 256 void (*post_filter)(void *), int (*assign_cpu)(void *, int), 257 const char *fmt, ...) 258 { 259 struct intr_event *ie; 260 va_list ap; 261 262 /* The only valid flag during creation is IE_SOFT. */ 263 if ((flags & ~IE_SOFT) != 0) 264 return (EINVAL); 265 ie = malloc(sizeof(struct intr_event), M_ITHREAD, M_WAITOK | M_ZERO); 266 ie->ie_source = source; 267 ie->ie_pre_ithread = pre_ithread; 268 ie->ie_post_ithread = post_ithread; 269 ie->ie_post_filter = post_filter; 270 ie->ie_assign_cpu = assign_cpu; 271 ie->ie_flags = flags; 272 ie->ie_irq = irq; 273 ie->ie_cpu = NOCPU; 274 CK_SLIST_INIT(&ie->ie_handlers); 275 mtx_init(&ie->ie_lock, "intr event", NULL, MTX_DEF); 276 277 va_start(ap, fmt); 278 vsnprintf(ie->ie_name, sizeof(ie->ie_name), fmt, ap); 279 va_end(ap); 280 strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname)); 281 mtx_lock(&event_lock); 282 TAILQ_INSERT_TAIL(&event_list, ie, ie_list); 283 mtx_unlock(&event_lock); 284 if (event != NULL) 285 *event = ie; 286 CTR2(KTR_INTR, "%s: created %s", __func__, ie->ie_name); 287 return (0); 288 } 289 290 /* 291 * Bind an interrupt event to the specified CPU. Note that not all 292 * platforms support binding an interrupt to a CPU. For those 293 * platforms this request will fail. Using a cpu id of NOCPU unbinds 294 * the interrupt event. 295 */ 296 static int 297 _intr_event_bind(struct intr_event *ie, int cpu, bool bindirq, bool bindithread) 298 { 299 lwpid_t id; 300 int error; 301 302 /* Need a CPU to bind to. */ 303 if (cpu != NOCPU && CPU_ABSENT(cpu)) 304 return (EINVAL); 305 306 if (ie->ie_assign_cpu == NULL) 307 return (EOPNOTSUPP); 308 309 error = priv_check(curthread, PRIV_SCHED_CPUSET_INTR); 310 if (error) 311 return (error); 312 313 /* 314 * If we have any ithreads try to set their mask first to verify 315 * permissions, etc. 316 */ 317 if (bindithread) { 318 mtx_lock(&ie->ie_lock); 319 if (ie->ie_thread != NULL) { 320 id = ie->ie_thread->it_thread->td_tid; 321 mtx_unlock(&ie->ie_lock); 322 error = cpuset_setithread(id, cpu); 323 if (error) 324 return (error); 325 } else 326 mtx_unlock(&ie->ie_lock); 327 } 328 if (bindirq) 329 error = ie->ie_assign_cpu(ie->ie_source, cpu); 330 if (error) { 331 if (bindithread) { 332 mtx_lock(&ie->ie_lock); 333 if (ie->ie_thread != NULL) { 334 cpu = ie->ie_cpu; 335 id = ie->ie_thread->it_thread->td_tid; 336 mtx_unlock(&ie->ie_lock); 337 (void)cpuset_setithread(id, cpu); 338 } else 339 mtx_unlock(&ie->ie_lock); 340 } 341 return (error); 342 } 343 344 if (bindirq) { 345 mtx_lock(&ie->ie_lock); 346 ie->ie_cpu = cpu; 347 mtx_unlock(&ie->ie_lock); 348 } 349 350 return (error); 351 } 352 353 /* 354 * Bind an interrupt event to the specified CPU. For supported platforms, any 355 * associated ithreads as well as the primary interrupt context will be bound 356 * to the specificed CPU. 357 */ 358 int 359 intr_event_bind(struct intr_event *ie, int cpu) 360 { 361 362 return (_intr_event_bind(ie, cpu, true, true)); 363 } 364 365 /* 366 * Bind an interrupt event to the specified CPU, but do not bind associated 367 * ithreads. 368 */ 369 int 370 intr_event_bind_irqonly(struct intr_event *ie, int cpu) 371 { 372 373 return (_intr_event_bind(ie, cpu, true, false)); 374 } 375 376 /* 377 * Bind an interrupt event's ithread to the specified CPU. 378 */ 379 int 380 intr_event_bind_ithread(struct intr_event *ie, int cpu) 381 { 382 383 return (_intr_event_bind(ie, cpu, false, true)); 384 } 385 386 /* 387 * Bind an interrupt event's ithread to the specified cpuset. 388 */ 389 int 390 intr_event_bind_ithread_cpuset(struct intr_event *ie, cpuset_t *cs) 391 { 392 lwpid_t id; 393 394 mtx_lock(&ie->ie_lock); 395 if (ie->ie_thread != NULL) { 396 id = ie->ie_thread->it_thread->td_tid; 397 mtx_unlock(&ie->ie_lock); 398 return (cpuset_setthread(id, cs)); 399 } else { 400 mtx_unlock(&ie->ie_lock); 401 } 402 return (ENODEV); 403 } 404 405 static struct intr_event * 406 intr_lookup(int irq) 407 { 408 struct intr_event *ie; 409 410 mtx_lock(&event_lock); 411 TAILQ_FOREACH(ie, &event_list, ie_list) 412 if (ie->ie_irq == irq && 413 (ie->ie_flags & IE_SOFT) == 0 && 414 CK_SLIST_FIRST(&ie->ie_handlers) != NULL) 415 break; 416 mtx_unlock(&event_lock); 417 return (ie); 418 } 419 420 int 421 intr_setaffinity(int irq, int mode, void *m) 422 { 423 struct intr_event *ie; 424 cpuset_t *mask; 425 int cpu, n; 426 427 mask = m; 428 cpu = NOCPU; 429 /* 430 * If we're setting all cpus we can unbind. Otherwise make sure 431 * only one cpu is in the set. 432 */ 433 if (CPU_CMP(cpuset_root, mask)) { 434 for (n = 0; n < CPU_SETSIZE; n++) { 435 if (!CPU_ISSET(n, mask)) 436 continue; 437 if (cpu != NOCPU) 438 return (EINVAL); 439 cpu = n; 440 } 441 } 442 ie = intr_lookup(irq); 443 if (ie == NULL) 444 return (ESRCH); 445 switch (mode) { 446 case CPU_WHICH_IRQ: 447 return (intr_event_bind(ie, cpu)); 448 case CPU_WHICH_INTRHANDLER: 449 return (intr_event_bind_irqonly(ie, cpu)); 450 case CPU_WHICH_ITHREAD: 451 return (intr_event_bind_ithread(ie, cpu)); 452 default: 453 return (EINVAL); 454 } 455 } 456 457 int 458 intr_getaffinity(int irq, int mode, void *m) 459 { 460 struct intr_event *ie; 461 struct thread *td; 462 struct proc *p; 463 cpuset_t *mask; 464 lwpid_t id; 465 int error; 466 467 mask = m; 468 ie = intr_lookup(irq); 469 if (ie == NULL) 470 return (ESRCH); 471 472 error = 0; 473 CPU_ZERO(mask); 474 switch (mode) { 475 case CPU_WHICH_IRQ: 476 case CPU_WHICH_INTRHANDLER: 477 mtx_lock(&ie->ie_lock); 478 if (ie->ie_cpu == NOCPU) 479 CPU_COPY(cpuset_root, mask); 480 else 481 CPU_SET(ie->ie_cpu, mask); 482 mtx_unlock(&ie->ie_lock); 483 break; 484 case CPU_WHICH_ITHREAD: 485 mtx_lock(&ie->ie_lock); 486 if (ie->ie_thread == NULL) { 487 mtx_unlock(&ie->ie_lock); 488 CPU_COPY(cpuset_root, mask); 489 } else { 490 id = ie->ie_thread->it_thread->td_tid; 491 mtx_unlock(&ie->ie_lock); 492 error = cpuset_which(CPU_WHICH_TID, id, &p, &td, NULL); 493 if (error != 0) 494 return (error); 495 CPU_COPY(&td->td_cpuset->cs_mask, mask); 496 PROC_UNLOCK(p); 497 } 498 default: 499 return (EINVAL); 500 } 501 return (0); 502 } 503 504 int 505 intr_event_destroy(struct intr_event *ie) 506 { 507 508 if (ie == NULL) 509 return (EINVAL); 510 511 mtx_lock(&event_lock); 512 mtx_lock(&ie->ie_lock); 513 if (!CK_SLIST_EMPTY(&ie->ie_handlers)) { 514 mtx_unlock(&ie->ie_lock); 515 mtx_unlock(&event_lock); 516 return (EBUSY); 517 } 518 TAILQ_REMOVE(&event_list, ie, ie_list); 519 #ifndef notyet 520 if (ie->ie_thread != NULL) { 521 ithread_destroy(ie->ie_thread); 522 ie->ie_thread = NULL; 523 } 524 #endif 525 mtx_unlock(&ie->ie_lock); 526 mtx_unlock(&event_lock); 527 mtx_destroy(&ie->ie_lock); 528 free(ie, M_ITHREAD); 529 return (0); 530 } 531 532 static struct intr_thread * 533 ithread_create(const char *name) 534 { 535 struct intr_thread *ithd; 536 struct thread *td; 537 int error; 538 539 ithd = malloc(sizeof(struct intr_thread), M_ITHREAD, M_WAITOK | M_ZERO); 540 541 error = kproc_kthread_add(ithread_loop, ithd, &intrproc, 542 &td, RFSTOPPED | RFHIGHPID, 543 0, "intr", "%s", name); 544 if (error) 545 panic("kproc_create() failed with %d", error); 546 thread_lock(td); 547 sched_class(td, PRI_ITHD); 548 TD_SET_IWAIT(td); 549 thread_unlock(td); 550 td->td_pflags |= TDP_ITHREAD; 551 ithd->it_thread = td; 552 CTR2(KTR_INTR, "%s: created %s", __func__, name); 553 return (ithd); 554 } 555 556 static void 557 ithread_destroy(struct intr_thread *ithread) 558 { 559 struct thread *td; 560 561 CTR2(KTR_INTR, "%s: killing %s", __func__, ithread->it_event->ie_name); 562 td = ithread->it_thread; 563 thread_lock(td); 564 ithread->it_flags |= IT_DEAD; 565 if (TD_AWAITING_INTR(td)) { 566 TD_CLR_IWAIT(td); 567 sched_add(td, SRQ_INTR); 568 } else 569 thread_unlock(td); 570 } 571 572 int 573 intr_event_add_handler(struct intr_event *ie, const char *name, 574 driver_filter_t filter, driver_intr_t handler, void *arg, u_char pri, 575 enum intr_type flags, void **cookiep) 576 { 577 struct intr_handler *ih, *temp_ih; 578 struct intr_handler **prevptr; 579 struct intr_thread *it; 580 581 if (ie == NULL || name == NULL || (handler == NULL && filter == NULL)) 582 return (EINVAL); 583 584 /* Allocate and populate an interrupt handler structure. */ 585 ih = malloc(sizeof(struct intr_handler), M_ITHREAD, M_WAITOK | M_ZERO); 586 ih->ih_filter = filter; 587 ih->ih_handler = handler; 588 ih->ih_argument = arg; 589 strlcpy(ih->ih_name, name, sizeof(ih->ih_name)); 590 ih->ih_event = ie; 591 ih->ih_pri = pri; 592 if (flags & INTR_EXCL) 593 ih->ih_flags = IH_EXCLUSIVE; 594 if (flags & INTR_MPSAFE) 595 ih->ih_flags |= IH_MPSAFE; 596 if (flags & INTR_ENTROPY) 597 ih->ih_flags |= IH_ENTROPY; 598 if (flags & INTR_TYPE_NET) 599 ih->ih_flags |= IH_NET; 600 601 /* We can only have one exclusive handler in a event. */ 602 mtx_lock(&ie->ie_lock); 603 if (!CK_SLIST_EMPTY(&ie->ie_handlers)) { 604 if ((flags & INTR_EXCL) || 605 (CK_SLIST_FIRST(&ie->ie_handlers)->ih_flags & IH_EXCLUSIVE)) { 606 mtx_unlock(&ie->ie_lock); 607 free(ih, M_ITHREAD); 608 return (EINVAL); 609 } 610 } 611 612 /* Create a thread if we need one. */ 613 while (ie->ie_thread == NULL && handler != NULL) { 614 if (ie->ie_flags & IE_ADDING_THREAD) 615 msleep(ie, &ie->ie_lock, 0, "ithread", 0); 616 else { 617 ie->ie_flags |= IE_ADDING_THREAD; 618 mtx_unlock(&ie->ie_lock); 619 it = ithread_create("intr: newborn"); 620 mtx_lock(&ie->ie_lock); 621 ie->ie_flags &= ~IE_ADDING_THREAD; 622 ie->ie_thread = it; 623 it->it_event = ie; 624 ithread_update(it); 625 wakeup(ie); 626 } 627 } 628 629 /* Add the new handler to the event in priority order. */ 630 CK_SLIST_FOREACH_PREVPTR(temp_ih, prevptr, &ie->ie_handlers, ih_next) { 631 if (temp_ih->ih_pri > ih->ih_pri) 632 break; 633 } 634 CK_SLIST_INSERT_PREVPTR(prevptr, temp_ih, ih, ih_next); 635 636 intr_event_update(ie); 637 638 CTR3(KTR_INTR, "%s: added %s to %s", __func__, ih->ih_name, 639 ie->ie_name); 640 mtx_unlock(&ie->ie_lock); 641 642 if (cookiep != NULL) 643 *cookiep = ih; 644 return (0); 645 } 646 647 /* 648 * Append a description preceded by a ':' to the name of the specified 649 * interrupt handler. 650 */ 651 int 652 intr_event_describe_handler(struct intr_event *ie, void *cookie, 653 const char *descr) 654 { 655 struct intr_handler *ih; 656 size_t space; 657 char *start; 658 659 mtx_lock(&ie->ie_lock); 660 #ifdef INVARIANTS 661 CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) { 662 if (ih == cookie) 663 break; 664 } 665 if (ih == NULL) { 666 mtx_unlock(&ie->ie_lock); 667 panic("handler %p not found in interrupt event %p", cookie, ie); 668 } 669 #endif 670 ih = cookie; 671 672 /* 673 * Look for an existing description by checking for an 674 * existing ":". This assumes device names do not include 675 * colons. If one is found, prepare to insert the new 676 * description at that point. If one is not found, find the 677 * end of the name to use as the insertion point. 678 */ 679 start = strchr(ih->ih_name, ':'); 680 if (start == NULL) 681 start = strchr(ih->ih_name, 0); 682 683 /* 684 * See if there is enough remaining room in the string for the 685 * description + ":". The "- 1" leaves room for the trailing 686 * '\0'. The "+ 1" accounts for the colon. 687 */ 688 space = sizeof(ih->ih_name) - (start - ih->ih_name) - 1; 689 if (strlen(descr) + 1 > space) { 690 mtx_unlock(&ie->ie_lock); 691 return (ENOSPC); 692 } 693 694 /* Append a colon followed by the description. */ 695 *start = ':'; 696 strcpy(start + 1, descr); 697 intr_event_update(ie); 698 mtx_unlock(&ie->ie_lock); 699 return (0); 700 } 701 702 /* 703 * Return the ie_source field from the intr_event an intr_handler is 704 * associated with. 705 */ 706 void * 707 intr_handler_source(void *cookie) 708 { 709 struct intr_handler *ih; 710 struct intr_event *ie; 711 712 ih = (struct intr_handler *)cookie; 713 if (ih == NULL) 714 return (NULL); 715 ie = ih->ih_event; 716 KASSERT(ie != NULL, 717 ("interrupt handler \"%s\" has a NULL interrupt event", 718 ih->ih_name)); 719 return (ie->ie_source); 720 } 721 722 /* 723 * If intr_event_handle() is running in the ISR context at the time of the call, 724 * then wait for it to complete. 725 */ 726 static void 727 intr_event_barrier(struct intr_event *ie) 728 { 729 int phase; 730 731 mtx_assert(&ie->ie_lock, MA_OWNED); 732 phase = ie->ie_phase; 733 734 /* 735 * Switch phase to direct future interrupts to the other active counter. 736 * Make sure that any preceding stores are visible before the switch. 737 */ 738 KASSERT(ie->ie_active[!phase] == 0, ("idle phase has activity")); 739 atomic_store_rel_int(&ie->ie_phase, !phase); 740 741 /* 742 * This code cooperates with wait-free iteration of ie_handlers 743 * in intr_event_handle. 744 * Make sure that the removal and the phase update are not reordered 745 * with the active count check. 746 * Note that no combination of acquire and release fences can provide 747 * that guarantee as Store->Load sequences can always be reordered. 748 */ 749 atomic_thread_fence_seq_cst(); 750 751 /* 752 * Now wait on the inactive phase. 753 * The acquire fence is needed so that all post-barrier accesses 754 * are after the check. 755 */ 756 while (ie->ie_active[phase] > 0) 757 cpu_spinwait(); 758 atomic_thread_fence_acq(); 759 } 760 761 static void 762 intr_handler_barrier(struct intr_handler *handler) 763 { 764 struct intr_event *ie; 765 766 ie = handler->ih_event; 767 mtx_assert(&ie->ie_lock, MA_OWNED); 768 KASSERT((handler->ih_flags & IH_DEAD) == 0, 769 ("update for a removed handler")); 770 771 if (ie->ie_thread == NULL) { 772 intr_event_barrier(ie); 773 return; 774 } 775 if ((handler->ih_flags & IH_CHANGED) == 0) { 776 handler->ih_flags |= IH_CHANGED; 777 intr_event_schedule_thread(ie); 778 } 779 while ((handler->ih_flags & IH_CHANGED) != 0) 780 msleep(handler, &ie->ie_lock, 0, "ih_barr", 0); 781 } 782 783 /* 784 * Sleep until an ithread finishes executing an interrupt handler. 785 * 786 * XXX Doesn't currently handle interrupt filters or fast interrupt 787 * handlers. This is intended for LinuxKPI drivers only. 788 * Do not use in BSD code. 789 */ 790 void 791 _intr_drain(int irq) 792 { 793 struct intr_event *ie; 794 struct intr_thread *ithd; 795 struct thread *td; 796 797 ie = intr_lookup(irq); 798 if (ie == NULL) 799 return; 800 if (ie->ie_thread == NULL) 801 return; 802 ithd = ie->ie_thread; 803 td = ithd->it_thread; 804 /* 805 * We set the flag and wait for it to be cleared to avoid 806 * long delays with potentially busy interrupt handlers 807 * were we to only sample TD_AWAITING_INTR() every tick. 808 */ 809 thread_lock(td); 810 if (!TD_AWAITING_INTR(td)) { 811 ithd->it_flags |= IT_WAIT; 812 while (ithd->it_flags & IT_WAIT) { 813 thread_unlock(td); 814 pause("idrain", 1); 815 thread_lock(td); 816 } 817 } 818 thread_unlock(td); 819 return; 820 } 821 822 int 823 intr_event_remove_handler(void *cookie) 824 { 825 struct intr_handler *handler = (struct intr_handler *)cookie; 826 struct intr_event *ie; 827 struct intr_handler *ih; 828 struct intr_handler **prevptr; 829 #ifdef notyet 830 int dead; 831 #endif 832 833 if (handler == NULL) 834 return (EINVAL); 835 ie = handler->ih_event; 836 KASSERT(ie != NULL, 837 ("interrupt handler \"%s\" has a NULL interrupt event", 838 handler->ih_name)); 839 840 mtx_lock(&ie->ie_lock); 841 CTR3(KTR_INTR, "%s: removing %s from %s", __func__, handler->ih_name, 842 ie->ie_name); 843 CK_SLIST_FOREACH_PREVPTR(ih, prevptr, &ie->ie_handlers, ih_next) { 844 if (ih == handler) 845 break; 846 } 847 if (ih == NULL) { 848 panic("interrupt handler \"%s\" not found in " 849 "interrupt event \"%s\"", handler->ih_name, ie->ie_name); 850 } 851 852 /* 853 * If there is no ithread, then directly remove the handler. Note that 854 * intr_event_handle() iterates ie_handlers in a lock-less fashion, so 855 * care needs to be taken to keep ie_handlers consistent and to free 856 * the removed handler only when ie_handlers is quiescent. 857 */ 858 if (ie->ie_thread == NULL) { 859 CK_SLIST_REMOVE_PREVPTR(prevptr, ih, ih_next); 860 intr_event_barrier(ie); 861 intr_event_update(ie); 862 mtx_unlock(&ie->ie_lock); 863 free(handler, M_ITHREAD); 864 return (0); 865 } 866 867 /* 868 * Let the interrupt thread do the job. 869 * The interrupt source is disabled when the interrupt thread is 870 * running, so it does not have to worry about interaction with 871 * intr_event_handle(). 872 */ 873 KASSERT((handler->ih_flags & IH_DEAD) == 0, 874 ("duplicate handle remove")); 875 handler->ih_flags |= IH_DEAD; 876 intr_event_schedule_thread(ie); 877 while (handler->ih_flags & IH_DEAD) 878 msleep(handler, &ie->ie_lock, 0, "iev_rmh", 0); 879 intr_event_update(ie); 880 881 #ifdef notyet 882 /* 883 * XXX: This could be bad in the case of ppbus(8). Also, I think 884 * this could lead to races of stale data when servicing an 885 * interrupt. 886 */ 887 dead = 1; 888 CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) { 889 if (ih->ih_handler != NULL) { 890 dead = 0; 891 break; 892 } 893 } 894 if (dead) { 895 ithread_destroy(ie->ie_thread); 896 ie->ie_thread = NULL; 897 } 898 #endif 899 mtx_unlock(&ie->ie_lock); 900 free(handler, M_ITHREAD); 901 return (0); 902 } 903 904 int 905 intr_event_suspend_handler(void *cookie) 906 { 907 struct intr_handler *handler = (struct intr_handler *)cookie; 908 struct intr_event *ie; 909 910 if (handler == NULL) 911 return (EINVAL); 912 ie = handler->ih_event; 913 KASSERT(ie != NULL, 914 ("interrupt handler \"%s\" has a NULL interrupt event", 915 handler->ih_name)); 916 mtx_lock(&ie->ie_lock); 917 handler->ih_flags |= IH_SUSP; 918 intr_handler_barrier(handler); 919 mtx_unlock(&ie->ie_lock); 920 return (0); 921 } 922 923 int 924 intr_event_resume_handler(void *cookie) 925 { 926 struct intr_handler *handler = (struct intr_handler *)cookie; 927 struct intr_event *ie; 928 929 if (handler == NULL) 930 return (EINVAL); 931 ie = handler->ih_event; 932 KASSERT(ie != NULL, 933 ("interrupt handler \"%s\" has a NULL interrupt event", 934 handler->ih_name)); 935 936 /* 937 * intr_handler_barrier() acts not only as a barrier, 938 * it also allows to check for any pending interrupts. 939 */ 940 mtx_lock(&ie->ie_lock); 941 handler->ih_flags &= ~IH_SUSP; 942 intr_handler_barrier(handler); 943 mtx_unlock(&ie->ie_lock); 944 return (0); 945 } 946 947 static int 948 intr_event_schedule_thread(struct intr_event *ie) 949 { 950 struct intr_entropy entropy; 951 struct intr_thread *it; 952 struct thread *td; 953 struct thread *ctd; 954 955 /* 956 * If no ithread or no handlers, then we have a stray interrupt. 957 */ 958 if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers) || 959 ie->ie_thread == NULL) 960 return (EINVAL); 961 962 ctd = curthread; 963 it = ie->ie_thread; 964 td = it->it_thread; 965 966 /* 967 * If any of the handlers for this ithread claim to be good 968 * sources of entropy, then gather some. 969 */ 970 if (ie->ie_hflags & IH_ENTROPY) { 971 entropy.event = (uintptr_t)ie; 972 entropy.td = ctd; 973 random_harvest_queue(&entropy, sizeof(entropy), RANDOM_INTERRUPT); 974 } 975 976 KASSERT(td->td_proc != NULL, ("ithread %s has no process", ie->ie_name)); 977 978 /* 979 * Set it_need to tell the thread to keep running if it is already 980 * running. Then, lock the thread and see if we actually need to 981 * put it on the runqueue. 982 * 983 * Use store_rel to arrange that the store to ih_need in 984 * swi_sched() is before the store to it_need and prepare for 985 * transfer of this order to loads in the ithread. 986 */ 987 atomic_store_rel_int(&it->it_need, 1); 988 thread_lock(td); 989 if (TD_AWAITING_INTR(td)) { 990 CTR3(KTR_INTR, "%s: schedule pid %d (%s)", __func__, td->td_proc->p_pid, 991 td->td_name); 992 TD_CLR_IWAIT(td); 993 sched_add(td, SRQ_INTR); 994 } else { 995 CTR5(KTR_INTR, "%s: pid %d (%s): it_need %d, state %d", 996 __func__, td->td_proc->p_pid, td->td_name, it->it_need, td->td_state); 997 thread_unlock(td); 998 } 999 1000 return (0); 1001 } 1002 1003 /* 1004 * Allow interrupt event binding for software interrupt handlers -- a no-op, 1005 * since interrupts are generated in software rather than being directed by 1006 * a PIC. 1007 */ 1008 static int 1009 swi_assign_cpu(void *arg, int cpu) 1010 { 1011 1012 return (0); 1013 } 1014 1015 /* 1016 * Add a software interrupt handler to a specified event. If a given event 1017 * is not specified, then a new event is created. 1018 */ 1019 int 1020 swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler, 1021 void *arg, int pri, enum intr_type flags, void **cookiep) 1022 { 1023 struct intr_event *ie; 1024 int error = 0; 1025 1026 if (flags & INTR_ENTROPY) 1027 return (EINVAL); 1028 1029 ie = (eventp != NULL) ? *eventp : NULL; 1030 1031 if (ie != NULL) { 1032 if (!(ie->ie_flags & IE_SOFT)) 1033 return (EINVAL); 1034 } else { 1035 error = intr_event_create(&ie, NULL, IE_SOFT, 0, 1036 NULL, NULL, NULL, swi_assign_cpu, "swi%d:", pri); 1037 if (error) 1038 return (error); 1039 if (eventp != NULL) 1040 *eventp = ie; 1041 } 1042 if (handler != NULL) { 1043 error = intr_event_add_handler(ie, name, NULL, handler, arg, 1044 PI_SWI(pri), flags, cookiep); 1045 } 1046 return (error); 1047 } 1048 1049 /* 1050 * Schedule a software interrupt thread. 1051 */ 1052 void 1053 swi_sched(void *cookie, int flags) 1054 { 1055 struct intr_handler *ih = (struct intr_handler *)cookie; 1056 struct intr_event *ie = ih->ih_event; 1057 struct intr_entropy entropy; 1058 int error __unused; 1059 1060 CTR3(KTR_INTR, "swi_sched: %s %s need=%d", ie->ie_name, ih->ih_name, 1061 ih->ih_need); 1062 1063 if ((flags & SWI_FROMNMI) == 0) { 1064 entropy.event = (uintptr_t)ih; 1065 entropy.td = curthread; 1066 random_harvest_queue(&entropy, sizeof(entropy), RANDOM_SWI); 1067 } 1068 1069 /* 1070 * Set ih_need for this handler so that if the ithread is already 1071 * running it will execute this handler on the next pass. Otherwise, 1072 * it will execute it the next time it runs. 1073 */ 1074 ih->ih_need = 1; 1075 1076 if (flags & SWI_DELAY) 1077 return; 1078 1079 if (flags & SWI_FROMNMI) { 1080 #if defined(SMP) && (defined(__i386__) || defined(__amd64__)) 1081 KASSERT(ie == clk_intr_event, 1082 ("SWI_FROMNMI used not with clk_intr_event")); 1083 ipi_self_from_nmi(IPI_SWI); 1084 #endif 1085 } else { 1086 VM_CNT_INC(v_soft); 1087 error = intr_event_schedule_thread(ie); 1088 KASSERT(error == 0, ("stray software interrupt")); 1089 } 1090 } 1091 1092 /* 1093 * Remove a software interrupt handler. Currently this code does not 1094 * remove the associated interrupt event if it becomes empty. Calling code 1095 * may do so manually via intr_event_destroy(), but that's not really 1096 * an optimal interface. 1097 */ 1098 int 1099 swi_remove(void *cookie) 1100 { 1101 1102 return (intr_event_remove_handler(cookie)); 1103 } 1104 1105 static void 1106 intr_event_execute_handlers(struct proc *p, struct intr_event *ie) 1107 { 1108 struct intr_handler *ih, *ihn, *ihp; 1109 1110 ihp = NULL; 1111 CK_SLIST_FOREACH_SAFE(ih, &ie->ie_handlers, ih_next, ihn) { 1112 /* 1113 * If this handler is marked for death, remove it from 1114 * the list of handlers and wake up the sleeper. 1115 */ 1116 if (ih->ih_flags & IH_DEAD) { 1117 mtx_lock(&ie->ie_lock); 1118 if (ihp == NULL) 1119 CK_SLIST_REMOVE_HEAD(&ie->ie_handlers, ih_next); 1120 else 1121 CK_SLIST_REMOVE_AFTER(ihp, ih_next); 1122 ih->ih_flags &= ~IH_DEAD; 1123 wakeup(ih); 1124 mtx_unlock(&ie->ie_lock); 1125 continue; 1126 } 1127 1128 /* 1129 * Now that we know that the current element won't be removed 1130 * update the previous element. 1131 */ 1132 ihp = ih; 1133 1134 if ((ih->ih_flags & IH_CHANGED) != 0) { 1135 mtx_lock(&ie->ie_lock); 1136 ih->ih_flags &= ~IH_CHANGED; 1137 wakeup(ih); 1138 mtx_unlock(&ie->ie_lock); 1139 } 1140 1141 /* Skip filter only handlers */ 1142 if (ih->ih_handler == NULL) 1143 continue; 1144 1145 /* Skip suspended handlers */ 1146 if ((ih->ih_flags & IH_SUSP) != 0) 1147 continue; 1148 1149 /* 1150 * For software interrupt threads, we only execute 1151 * handlers that have their need flag set. Hardware 1152 * interrupt threads always invoke all of their handlers. 1153 * 1154 * ih_need can only be 0 or 1. Failed cmpset below 1155 * means that there is no request to execute handlers, 1156 * so a retry of the cmpset is not needed. 1157 */ 1158 if ((ie->ie_flags & IE_SOFT) != 0 && 1159 atomic_cmpset_int(&ih->ih_need, 1, 0) == 0) 1160 continue; 1161 1162 /* Execute this handler. */ 1163 CTR6(KTR_INTR, "%s: pid %d exec %p(%p) for %s flg=%x", 1164 __func__, p->p_pid, (void *)ih->ih_handler, 1165 ih->ih_argument, ih->ih_name, ih->ih_flags); 1166 1167 if (!(ih->ih_flags & IH_MPSAFE)) 1168 mtx_lock(&Giant); 1169 ih->ih_handler(ih->ih_argument); 1170 if (!(ih->ih_flags & IH_MPSAFE)) 1171 mtx_unlock(&Giant); 1172 } 1173 } 1174 1175 static void 1176 ithread_execute_handlers(struct proc *p, struct intr_event *ie) 1177 { 1178 1179 /* Interrupt handlers should not sleep. */ 1180 if (!(ie->ie_flags & IE_SOFT)) 1181 THREAD_NO_SLEEPING(); 1182 intr_event_execute_handlers(p, ie); 1183 if (!(ie->ie_flags & IE_SOFT)) 1184 THREAD_SLEEPING_OK(); 1185 1186 /* 1187 * Interrupt storm handling: 1188 * 1189 * If this interrupt source is currently storming, then throttle 1190 * it to only fire the handler once per clock tick. 1191 * 1192 * If this interrupt source is not currently storming, but the 1193 * number of back to back interrupts exceeds the storm threshold, 1194 * then enter storming mode. 1195 */ 1196 if (intr_storm_threshold != 0 && ie->ie_count >= intr_storm_threshold && 1197 !(ie->ie_flags & IE_SOFT)) { 1198 /* Report the message only once every second. */ 1199 if (ppsratecheck(&ie->ie_warntm, &ie->ie_warncnt, 1)) { 1200 printf( 1201 "interrupt storm detected on \"%s\"; throttling interrupt source\n", 1202 ie->ie_name); 1203 } 1204 pause("istorm", 1); 1205 } else 1206 ie->ie_count++; 1207 1208 /* 1209 * Now that all the handlers have had a chance to run, reenable 1210 * the interrupt source. 1211 */ 1212 if (ie->ie_post_ithread != NULL) 1213 ie->ie_post_ithread(ie->ie_source); 1214 } 1215 1216 /* 1217 * This is the main code for interrupt threads. 1218 */ 1219 static void 1220 ithread_loop(void *arg) 1221 { 1222 struct epoch_tracker et; 1223 struct intr_thread *ithd; 1224 struct intr_event *ie; 1225 struct thread *td; 1226 struct proc *p; 1227 int wake, epoch_count; 1228 bool needs_epoch; 1229 1230 td = curthread; 1231 p = td->td_proc; 1232 ithd = (struct intr_thread *)arg; 1233 KASSERT(ithd->it_thread == td, 1234 ("%s: ithread and proc linkage out of sync", __func__)); 1235 ie = ithd->it_event; 1236 ie->ie_count = 0; 1237 wake = 0; 1238 1239 /* 1240 * As long as we have interrupts outstanding, go through the 1241 * list of handlers, giving each one a go at it. 1242 */ 1243 for (;;) { 1244 /* 1245 * If we are an orphaned thread, then just die. 1246 */ 1247 if (ithd->it_flags & IT_DEAD) { 1248 CTR3(KTR_INTR, "%s: pid %d (%s) exiting", __func__, 1249 p->p_pid, td->td_name); 1250 free(ithd, M_ITHREAD); 1251 kthread_exit(); 1252 } 1253 1254 /* 1255 * Service interrupts. If another interrupt arrives while 1256 * we are running, it will set it_need to note that we 1257 * should make another pass. 1258 * 1259 * The load_acq part of the following cmpset ensures 1260 * that the load of ih_need in ithread_execute_handlers() 1261 * is ordered after the load of it_need here. 1262 */ 1263 needs_epoch = 1264 (atomic_load_int(&ie->ie_hflags) & IH_NET) != 0; 1265 if (needs_epoch) { 1266 epoch_count = 0; 1267 NET_EPOCH_ENTER(et); 1268 } 1269 while (atomic_cmpset_acq_int(&ithd->it_need, 1, 0) != 0) { 1270 ithread_execute_handlers(p, ie); 1271 if (needs_epoch && 1272 ++epoch_count >= intr_epoch_batch) { 1273 NET_EPOCH_EXIT(et); 1274 epoch_count = 0; 1275 NET_EPOCH_ENTER(et); 1276 } 1277 } 1278 if (needs_epoch) 1279 NET_EPOCH_EXIT(et); 1280 WITNESS_WARN(WARN_PANIC, NULL, "suspending ithread"); 1281 mtx_assert(&Giant, MA_NOTOWNED); 1282 1283 /* 1284 * Processed all our interrupts. Now get the sched 1285 * lock. This may take a while and it_need may get 1286 * set again, so we have to check it again. 1287 */ 1288 thread_lock(td); 1289 if (atomic_load_acq_int(&ithd->it_need) == 0 && 1290 (ithd->it_flags & (IT_DEAD | IT_WAIT)) == 0) { 1291 TD_SET_IWAIT(td); 1292 ie->ie_count = 0; 1293 mi_switch(SW_VOL | SWT_IWAIT); 1294 } else { 1295 if (ithd->it_flags & IT_WAIT) { 1296 wake = 1; 1297 ithd->it_flags &= ~IT_WAIT; 1298 } 1299 thread_unlock(td); 1300 } 1301 if (wake) { 1302 wakeup(ithd); 1303 wake = 0; 1304 } 1305 } 1306 } 1307 1308 /* 1309 * Main interrupt handling body. 1310 * 1311 * Input: 1312 * o ie: the event connected to this interrupt. 1313 * o frame: some archs (i.e. i386) pass a frame to some. 1314 * handlers as their main argument. 1315 * Return value: 1316 * o 0: everything ok. 1317 * o EINVAL: stray interrupt. 1318 */ 1319 int 1320 intr_event_handle(struct intr_event *ie, struct trapframe *frame) 1321 { 1322 struct intr_handler *ih; 1323 struct trapframe *oldframe; 1324 struct thread *td; 1325 int phase; 1326 int ret; 1327 bool filter, thread; 1328 1329 td = curthread; 1330 1331 #ifdef KSTACK_USAGE_PROF 1332 intr_prof_stack_use(td, frame); 1333 #endif 1334 1335 /* An interrupt with no event or handlers is a stray interrupt. */ 1336 if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers)) 1337 return (EINVAL); 1338 1339 /* 1340 * Execute fast interrupt handlers directly. 1341 * To support clock handlers, if a handler registers 1342 * with a NULL argument, then we pass it a pointer to 1343 * a trapframe as its argument. 1344 */ 1345 td->td_intr_nesting_level++; 1346 filter = false; 1347 thread = false; 1348 ret = 0; 1349 critical_enter(); 1350 oldframe = td->td_intr_frame; 1351 td->td_intr_frame = frame; 1352 1353 phase = ie->ie_phase; 1354 atomic_add_int(&ie->ie_active[phase], 1); 1355 1356 /* 1357 * This fence is required to ensure that no later loads are 1358 * re-ordered before the ie_active store. 1359 */ 1360 atomic_thread_fence_seq_cst(); 1361 1362 CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) { 1363 if ((ih->ih_flags & IH_SUSP) != 0) 1364 continue; 1365 if ((ie->ie_flags & IE_SOFT) != 0 && ih->ih_need == 0) 1366 continue; 1367 if (ih->ih_filter == NULL) { 1368 thread = true; 1369 continue; 1370 } 1371 CTR4(KTR_INTR, "%s: exec %p(%p) for %s", __func__, 1372 ih->ih_filter, ih->ih_argument == NULL ? frame : 1373 ih->ih_argument, ih->ih_name); 1374 if (ih->ih_argument == NULL) 1375 ret = ih->ih_filter(frame); 1376 else 1377 ret = ih->ih_filter(ih->ih_argument); 1378 KASSERT(ret == FILTER_STRAY || 1379 ((ret & (FILTER_SCHEDULE_THREAD | FILTER_HANDLED)) != 0 && 1380 (ret & ~(FILTER_SCHEDULE_THREAD | FILTER_HANDLED)) == 0), 1381 ("%s: incorrect return value %#x from %s", __func__, ret, 1382 ih->ih_name)); 1383 filter = filter || ret == FILTER_HANDLED; 1384 1385 /* 1386 * Wrapper handler special handling: 1387 * 1388 * in some particular cases (like pccard and pccbb), 1389 * the _real_ device handler is wrapped in a couple of 1390 * functions - a filter wrapper and an ithread wrapper. 1391 * In this case (and just in this case), the filter wrapper 1392 * could ask the system to schedule the ithread and mask 1393 * the interrupt source if the wrapped handler is composed 1394 * of just an ithread handler. 1395 * 1396 * TODO: write a generic wrapper to avoid people rolling 1397 * their own. 1398 */ 1399 if (!thread) { 1400 if (ret == FILTER_SCHEDULE_THREAD) 1401 thread = true; 1402 } 1403 } 1404 atomic_add_rel_int(&ie->ie_active[phase], -1); 1405 1406 td->td_intr_frame = oldframe; 1407 1408 if (thread) { 1409 if (ie->ie_pre_ithread != NULL) 1410 ie->ie_pre_ithread(ie->ie_source); 1411 } else { 1412 if (ie->ie_post_filter != NULL) 1413 ie->ie_post_filter(ie->ie_source); 1414 } 1415 1416 /* Schedule the ithread if needed. */ 1417 if (thread) { 1418 int error __unused; 1419 1420 error = intr_event_schedule_thread(ie); 1421 KASSERT(error == 0, ("bad stray interrupt")); 1422 } 1423 critical_exit(); 1424 td->td_intr_nesting_level--; 1425 #ifdef notyet 1426 /* The interrupt is not aknowledged by any filter and has no ithread. */ 1427 if (!thread && !filter) 1428 return (EINVAL); 1429 #endif 1430 return (0); 1431 } 1432 1433 #ifdef DDB 1434 /* 1435 * Dump details about an interrupt handler 1436 */ 1437 static void 1438 db_dump_intrhand(struct intr_handler *ih) 1439 { 1440 int comma; 1441 1442 db_printf("\t%-10s ", ih->ih_name); 1443 switch (ih->ih_pri) { 1444 case PI_REALTIME: 1445 db_printf("CLK "); 1446 break; 1447 case PI_AV: 1448 db_printf("AV "); 1449 break; 1450 case PI_TTY: 1451 db_printf("TTY "); 1452 break; 1453 case PI_NET: 1454 db_printf("NET "); 1455 break; 1456 case PI_DISK: 1457 db_printf("DISK"); 1458 break; 1459 case PI_DULL: 1460 db_printf("DULL"); 1461 break; 1462 default: 1463 if (ih->ih_pri >= PI_SOFT) 1464 db_printf("SWI "); 1465 else 1466 db_printf("%4u", ih->ih_pri); 1467 break; 1468 } 1469 db_printf(" "); 1470 if (ih->ih_filter != NULL) { 1471 db_printf("[F]"); 1472 db_printsym((uintptr_t)ih->ih_filter, DB_STGY_PROC); 1473 } 1474 if (ih->ih_handler != NULL) { 1475 if (ih->ih_filter != NULL) 1476 db_printf(","); 1477 db_printf("[H]"); 1478 db_printsym((uintptr_t)ih->ih_handler, DB_STGY_PROC); 1479 } 1480 db_printf("(%p)", ih->ih_argument); 1481 if (ih->ih_need || 1482 (ih->ih_flags & (IH_EXCLUSIVE | IH_ENTROPY | IH_DEAD | 1483 IH_MPSAFE)) != 0) { 1484 db_printf(" {"); 1485 comma = 0; 1486 if (ih->ih_flags & IH_EXCLUSIVE) { 1487 if (comma) 1488 db_printf(", "); 1489 db_printf("EXCL"); 1490 comma = 1; 1491 } 1492 if (ih->ih_flags & IH_ENTROPY) { 1493 if (comma) 1494 db_printf(", "); 1495 db_printf("ENTROPY"); 1496 comma = 1; 1497 } 1498 if (ih->ih_flags & IH_DEAD) { 1499 if (comma) 1500 db_printf(", "); 1501 db_printf("DEAD"); 1502 comma = 1; 1503 } 1504 if (ih->ih_flags & IH_MPSAFE) { 1505 if (comma) 1506 db_printf(", "); 1507 db_printf("MPSAFE"); 1508 comma = 1; 1509 } 1510 if (ih->ih_need) { 1511 if (comma) 1512 db_printf(", "); 1513 db_printf("NEED"); 1514 } 1515 db_printf("}"); 1516 } 1517 db_printf("\n"); 1518 } 1519 1520 /* 1521 * Dump details about a event. 1522 */ 1523 void 1524 db_dump_intr_event(struct intr_event *ie, int handlers) 1525 { 1526 struct intr_handler *ih; 1527 struct intr_thread *it; 1528 int comma; 1529 1530 db_printf("%s ", ie->ie_fullname); 1531 it = ie->ie_thread; 1532 if (it != NULL) 1533 db_printf("(pid %d)", it->it_thread->td_proc->p_pid); 1534 else 1535 db_printf("(no thread)"); 1536 if ((ie->ie_flags & (IE_SOFT | IE_ADDING_THREAD)) != 0 || 1537 (it != NULL && it->it_need)) { 1538 db_printf(" {"); 1539 comma = 0; 1540 if (ie->ie_flags & IE_SOFT) { 1541 db_printf("SOFT"); 1542 comma = 1; 1543 } 1544 if (ie->ie_flags & IE_ADDING_THREAD) { 1545 if (comma) 1546 db_printf(", "); 1547 db_printf("ADDING_THREAD"); 1548 comma = 1; 1549 } 1550 if (it != NULL && it->it_need) { 1551 if (comma) 1552 db_printf(", "); 1553 db_printf("NEED"); 1554 } 1555 db_printf("}"); 1556 } 1557 db_printf("\n"); 1558 1559 if (handlers) 1560 CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) 1561 db_dump_intrhand(ih); 1562 } 1563 1564 /* 1565 * Dump data about interrupt handlers 1566 */ 1567 DB_SHOW_COMMAND(intr, db_show_intr) 1568 { 1569 struct intr_event *ie; 1570 int all, verbose; 1571 1572 verbose = strchr(modif, 'v') != NULL; 1573 all = strchr(modif, 'a') != NULL; 1574 TAILQ_FOREACH(ie, &event_list, ie_list) { 1575 if (!all && CK_SLIST_EMPTY(&ie->ie_handlers)) 1576 continue; 1577 db_dump_intr_event(ie, verbose); 1578 if (db_pager_quit) 1579 break; 1580 } 1581 } 1582 #endif /* DDB */ 1583 1584 /* 1585 * Start standard software interrupt threads 1586 */ 1587 static void 1588 start_softintr(void *dummy) 1589 { 1590 1591 if (swi_add(&clk_intr_event, "clk", NULL, NULL, SWI_CLOCK, 1592 INTR_MPSAFE, NULL)) 1593 panic("died while creating clk swi ithread"); 1594 } 1595 SYSINIT(start_softintr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_softintr, 1596 NULL); 1597 1598 /* 1599 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt. 1600 * The data for this machine dependent, and the declarations are in machine 1601 * dependent code. The layout of intrnames and intrcnt however is machine 1602 * independent. 1603 * 1604 * We do not know the length of intrcnt and intrnames at compile time, so 1605 * calculate things at run time. 1606 */ 1607 static int 1608 sysctl_intrnames(SYSCTL_HANDLER_ARGS) 1609 { 1610 return (sysctl_handle_opaque(oidp, intrnames, sintrnames, req)); 1611 } 1612 1613 SYSCTL_PROC(_hw, OID_AUTO, intrnames, 1614 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1615 sysctl_intrnames, "", 1616 "Interrupt Names"); 1617 1618 static int 1619 sysctl_intrcnt(SYSCTL_HANDLER_ARGS) 1620 { 1621 #ifdef SCTL_MASK32 1622 uint32_t *intrcnt32; 1623 unsigned i; 1624 int error; 1625 1626 if (req->flags & SCTL_MASK32) { 1627 if (!req->oldptr) 1628 return (sysctl_handle_opaque(oidp, NULL, sintrcnt / 2, req)); 1629 intrcnt32 = malloc(sintrcnt / 2, M_TEMP, M_NOWAIT); 1630 if (intrcnt32 == NULL) 1631 return (ENOMEM); 1632 for (i = 0; i < sintrcnt / sizeof (u_long); i++) 1633 intrcnt32[i] = intrcnt[i]; 1634 error = sysctl_handle_opaque(oidp, intrcnt32, sintrcnt / 2, req); 1635 free(intrcnt32, M_TEMP); 1636 return (error); 1637 } 1638 #endif 1639 return (sysctl_handle_opaque(oidp, intrcnt, sintrcnt, req)); 1640 } 1641 1642 SYSCTL_PROC(_hw, OID_AUTO, intrcnt, 1643 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1644 sysctl_intrcnt, "", 1645 "Interrupt Counts"); 1646 1647 #ifdef DDB 1648 /* 1649 * DDB command to dump the interrupt statistics. 1650 */ 1651 DB_SHOW_COMMAND(intrcnt, db_show_intrcnt) 1652 { 1653 u_long *i; 1654 char *cp; 1655 u_int j; 1656 1657 cp = intrnames; 1658 j = 0; 1659 for (i = intrcnt; j < (sintrcnt / sizeof(u_long)) && !db_pager_quit; 1660 i++, j++) { 1661 if (*cp == '\0') 1662 break; 1663 if (*i != 0) 1664 db_printf("%s\t%lu\n", cp, *i); 1665 cp += strlen(cp) + 1; 1666 } 1667 } 1668 #endif
Cache object: a914bbe9b990e4f310c731ded7698091
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]