kern_intr.c revision 177901
1/*- 2 * Copyright (c) 1997, Stefan Esser <se@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_intr.c 177901 2008-04-04 01:03:23Z jeff $"); 29 30#include "opt_ddb.h" 31 32#include <sys/param.h> 33#include <sys/bus.h> 34#include <sys/conf.h> 35#include <sys/rtprio.h> 36#include <sys/systm.h> 37#include <sys/interrupt.h> 38#include <sys/kernel.h> 39#include <sys/kthread.h> 40#include <sys/ktr.h> 41#include <sys/limits.h> 42#include <sys/lock.h> 43#include <sys/malloc.h> 44#include <sys/mutex.h> 45#include <sys/proc.h> 46#include <sys/random.h> 47#include <sys/resourcevar.h> 48#include <sys/sched.h> 49#include <sys/smp.h> 50#include <sys/sysctl.h> 51#include <sys/unistd.h> 52#include <sys/vmmeter.h> 53#include <machine/atomic.h> 54#include <machine/cpu.h> 55#include <machine/md_var.h> 56#include <machine/stdarg.h> 57#ifdef DDB 58#include <ddb/ddb.h> 59#include <ddb/db_sym.h> 60#endif 61 62/* 63 * Describe an interrupt thread. There is one of these per interrupt event. 64 */ 65struct intr_thread { 66 struct intr_event *it_event; 67 struct thread *it_thread; /* Kernel thread. */ 68 int it_flags; /* (j) IT_* flags. */ 69 int it_need; /* Needs service. */ 70}; 71 72/* Interrupt thread flags kept in it_flags */ 73#define IT_DEAD 0x000001 /* Thread is waiting to exit. */ 74 75struct intr_entropy { 76 struct thread *td; 77 uintptr_t event; 78}; 79 80struct intr_event *clk_intr_event; 81struct intr_event *tty_intr_event; 82void *vm_ih; 83struct proc *intrproc; 84 85static MALLOC_DEFINE(M_ITHREAD, "ithread", "Interrupt Threads"); 86 87static int intr_storm_threshold = 1000; 88TUNABLE_INT("hw.intr_storm_threshold", &intr_storm_threshold); 89SYSCTL_INT(_hw, OID_AUTO, intr_storm_threshold, CTLFLAG_RW, 90 &intr_storm_threshold, 0, 91 "Number of consecutive interrupts before storm protection is enabled"); 92static TAILQ_HEAD(, intr_event) event_list = 93 TAILQ_HEAD_INITIALIZER(event_list); 94 95static void intr_event_update(struct intr_event *ie); 96#ifdef INTR_FILTER 97static struct intr_thread *ithread_create(const char *name, 98 struct intr_handler *ih); 99#else 100static struct intr_thread *ithread_create(const char *name); 101#endif 102static void ithread_destroy(struct intr_thread *ithread); 103static void ithread_execute_handlers(struct proc *p, 104 struct intr_event *ie); 105#ifdef INTR_FILTER 106static void priv_ithread_execute_handler(struct proc *p, 107 struct intr_handler *ih); 108#endif 109static void ithread_loop(void *); 110static void ithread_update(struct intr_thread *ithd); 111static void start_softintr(void *); 112 113/* Map an interrupt type to an ithread priority. */ 114u_char 115intr_priority(enum intr_type flags) 116{ 117 u_char pri; 118 119 flags &= (INTR_TYPE_TTY | INTR_TYPE_BIO | INTR_TYPE_NET | 120 INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK | INTR_TYPE_AV); 121 switch (flags) { 122 case INTR_TYPE_TTY: 123 pri = PI_TTYLOW; 124 break; 125 case INTR_TYPE_BIO: 126 /* 127 * XXX We need to refine this. BSD/OS distinguishes 128 * between tape and disk priorities. 129 */ 130 pri = PI_DISK; 131 break; 132 case INTR_TYPE_NET: 133 pri = PI_NET; 134 break; 135 case INTR_TYPE_CAM: 136 pri = PI_DISK; /* XXX or PI_CAM? */ 137 break; 138 case INTR_TYPE_AV: /* Audio/video */ 139 pri = PI_AV; 140 break; 141 case INTR_TYPE_CLK: 142 pri = PI_REALTIME; 143 break; 144 case INTR_TYPE_MISC: 145 pri = PI_DULL; /* don't care */ 146 break; 147 default: 148 /* We didn't specify an interrupt level. */ 149 panic("intr_priority: no interrupt type in flags"); 150 } 151 152 return pri; 153} 154 155/* 156 * Update an ithread based on the associated intr_event. 157 */ 158static void 159ithread_update(struct intr_thread *ithd) 160{ 161 struct intr_event *ie; 162 struct thread *td; 163 u_char pri; 164 165 ie = ithd->it_event; 166 td = ithd->it_thread; 167 168 /* Determine the overall priority of this event. */ 169 if (TAILQ_EMPTY(&ie->ie_handlers)) 170 pri = PRI_MAX_ITHD; 171 else 172 pri = TAILQ_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 thread_lock(td); 177 sched_prio(td, pri); 178 thread_unlock(td); 179} 180 181/* 182 * Regenerate the full name of an interrupt event and update its priority. 183 */ 184static void 185intr_event_update(struct intr_event *ie) 186{ 187 struct intr_handler *ih; 188 char *last; 189 int missed, space; 190 191 /* Start off with no entropy and just the name of the event. */ 192 mtx_assert(&ie->ie_lock, MA_OWNED); 193 strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname)); 194 ie->ie_flags &= ~IE_ENTROPY; 195 missed = 0; 196 space = 1; 197 198 /* Run through all the handlers updating values. */ 199 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) { 200 if (strlen(ie->ie_fullname) + strlen(ih->ih_name) + 1 < 201 sizeof(ie->ie_fullname)) { 202 strcat(ie->ie_fullname, " "); 203 strcat(ie->ie_fullname, ih->ih_name); 204 space = 0; 205 } else 206 missed++; 207 if (ih->ih_flags & IH_ENTROPY) 208 ie->ie_flags |= IE_ENTROPY; 209 } 210 211 /* 212 * If the handler names were too long, add +'s to indicate missing 213 * names. If we run out of room and still have +'s to add, change 214 * the last character from a + to a *. 215 */ 216 last = &ie->ie_fullname[sizeof(ie->ie_fullname) - 2]; 217 while (missed-- > 0) { 218 if (strlen(ie->ie_fullname) + 1 == sizeof(ie->ie_fullname)) { 219 if (*last == '+') { 220 *last = '*'; 221 break; 222 } else 223 *last = '+'; 224 } else if (space) { 225 strcat(ie->ie_fullname, " +"); 226 space = 0; 227 } else 228 strcat(ie->ie_fullname, "+"); 229 } 230 231 /* 232 * If this event has an ithread, update it's priority and 233 * name. 234 */ 235 if (ie->ie_thread != NULL) 236 ithread_update(ie->ie_thread); 237 CTR2(KTR_INTR, "%s: updated %s", __func__, ie->ie_fullname); 238} 239 240int 241intr_event_create(struct intr_event **event, void *source,int flags, 242 void (*disable)(void *), void (*enable)(void *), void (*eoi)(void *), 243 int (*assign_cpu)(void *, u_char), const char *fmt, ...) 244{ 245 struct intr_event *ie; 246 va_list ap; 247 248 /* The only valid flag during creation is IE_SOFT. */ 249 if ((flags & ~IE_SOFT) != 0) 250 return (EINVAL); 251 ie = malloc(sizeof(struct intr_event), M_ITHREAD, M_WAITOK | M_ZERO); 252 ie->ie_source = source; 253 ie->ie_disable = disable; 254 ie->ie_enable = enable; 255 ie->ie_eoi = eoi; 256 ie->ie_assign_cpu = assign_cpu; 257 ie->ie_flags = flags; 258 ie->ie_cpu = NOCPU; 259 TAILQ_INIT(&ie->ie_handlers); 260 mtx_init(&ie->ie_lock, "intr event", NULL, MTX_DEF); 261 262 va_start(ap, fmt); 263 vsnprintf(ie->ie_name, sizeof(ie->ie_name), fmt, ap); 264 va_end(ap); 265 strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname)); 266 mtx_pool_lock(mtxpool_sleep, &event_list); 267 TAILQ_INSERT_TAIL(&event_list, ie, ie_list); 268 mtx_pool_unlock(mtxpool_sleep, &event_list); 269 if (event != NULL) 270 *event = ie; 271 CTR2(KTR_INTR, "%s: created %s", __func__, ie->ie_name); 272 return (0); 273} 274 275/* 276 * Bind an interrupt event to the specified CPU. Note that not all 277 * platforms support binding an interrupt to a CPU. For those 278 * platforms this request will fail. For supported platforms, any 279 * associated ithreads as well as the primary interrupt context will 280 * be bound to the specificed CPU. Using a cpu id of NOCPU unbinds 281 * the interrupt event. 282 */ 283int 284intr_event_bind(struct intr_event *ie, u_char cpu) 285{ 286 struct thread *td; 287 int error; 288 289 /* Need a CPU to bind to. */ 290 if (cpu != NOCPU && CPU_ABSENT(cpu)) 291 return (EINVAL); 292 293 if (ie->ie_assign_cpu == NULL) 294 return (EOPNOTSUPP); 295 296 /* Don't allow a bind request if the interrupt is already bound. */ 297 mtx_lock(&ie->ie_lock); 298 if (ie->ie_cpu != NOCPU && cpu != NOCPU) { 299 mtx_unlock(&ie->ie_lock); 300 return (EBUSY); 301 } 302 mtx_unlock(&ie->ie_lock); 303 304 error = ie->ie_assign_cpu(ie->ie_source, cpu); 305 if (error) 306 return (error); 307 mtx_lock(&ie->ie_lock); 308 if (ie->ie_thread != NULL) 309 td = ie->ie_thread->it_thread; 310 else 311 td = NULL; 312 if (td != NULL) 313 thread_lock(td); 314 ie->ie_cpu = cpu; 315 if (td != NULL) 316 thread_unlock(td); 317 mtx_unlock(&ie->ie_lock); 318 return (0); 319} 320 321int 322intr_event_destroy(struct intr_event *ie) 323{ 324 325 mtx_lock(&ie->ie_lock); 326 if (!TAILQ_EMPTY(&ie->ie_handlers)) { 327 mtx_unlock(&ie->ie_lock); 328 return (EBUSY); 329 } 330 mtx_pool_lock(mtxpool_sleep, &event_list); 331 TAILQ_REMOVE(&event_list, ie, ie_list); 332 mtx_pool_unlock(mtxpool_sleep, &event_list); 333#ifndef notyet 334 if (ie->ie_thread != NULL) { 335 ithread_destroy(ie->ie_thread); 336 ie->ie_thread = NULL; 337 } 338#endif 339 mtx_unlock(&ie->ie_lock); 340 mtx_destroy(&ie->ie_lock); 341 free(ie, M_ITHREAD); 342 return (0); 343} 344 345#ifndef INTR_FILTER 346static struct intr_thread * 347ithread_create(const char *name) 348{ 349 struct intr_thread *ithd; 350 struct thread *td; 351 int error; 352 353 ithd = malloc(sizeof(struct intr_thread), M_ITHREAD, M_WAITOK | M_ZERO); 354 355 error = kproc_kthread_add(ithread_loop, ithd, &intrproc, 356 &td, RFSTOPPED | RFHIGHPID, 357 0, "intr", "%s", name); 358 if (error) 359 panic("kproc_create() failed with %d", error); 360 thread_lock(td); 361 sched_class(td, PRI_ITHD); 362 TD_SET_IWAIT(td); 363 thread_unlock(td); 364 td->td_pflags |= TDP_ITHREAD; 365 ithd->it_thread = td; 366 CTR2(KTR_INTR, "%s: created %s", __func__, name); 367 return (ithd); 368} 369#else 370static struct intr_thread * 371ithread_create(const char *name, struct intr_handler *ih) 372{ 373 struct intr_thread *ithd; 374 struct thread *td; 375 int error; 376 377 ithd = malloc(sizeof(struct intr_thread), M_ITHREAD, M_WAITOK | M_ZERO); 378 379 error = kproc_kthread_add(ithread_loop, ih, &intrproc, 380 &td, RFSTOPPED | RFHIGHPID, 381 0, "intr", "%s", name); 382 if (error) 383 panic("kproc_create() failed with %d", error); 384 thread_lock(td); 385 sched_class(td, PRI_ITHD); 386 TD_SET_IWAIT(td); 387 thread_unlock(td); 388 td->td_pflags |= TDP_ITHREAD; 389 ithd->it_thread = td; 390 CTR2(KTR_INTR, "%s: created %s", __func__, name); 391 return (ithd); 392} 393#endif 394 395static void 396ithread_destroy(struct intr_thread *ithread) 397{ 398 struct thread *td; 399 400 CTR2(KTR_INTR, "%s: killing %s", __func__, ithread->it_event->ie_name); 401 td = ithread->it_thread; 402 thread_lock(td); 403 ithread->it_flags |= IT_DEAD; 404 if (TD_AWAITING_INTR(td)) { 405 TD_CLR_IWAIT(td); 406 sched_add(td, SRQ_INTR); 407 } 408 thread_unlock(td); 409} 410 411#ifndef INTR_FILTER 412int 413intr_event_add_handler(struct intr_event *ie, const char *name, 414 driver_filter_t filter, driver_intr_t handler, void *arg, u_char pri, 415 enum intr_type flags, void **cookiep) 416{ 417 struct intr_handler *ih, *temp_ih; 418 struct intr_thread *it; 419 420 if (ie == NULL || name == NULL || (handler == NULL && filter == NULL)) 421 return (EINVAL); 422 423 /* Allocate and populate an interrupt handler structure. */ 424 ih = malloc(sizeof(struct intr_handler), M_ITHREAD, M_WAITOK | M_ZERO); 425 ih->ih_filter = filter; 426 ih->ih_handler = handler; 427 ih->ih_argument = arg; 428 ih->ih_name = name; 429 ih->ih_event = ie; 430 ih->ih_pri = pri; 431 if (flags & INTR_EXCL) 432 ih->ih_flags = IH_EXCLUSIVE; 433 if (flags & INTR_MPSAFE) 434 ih->ih_flags |= IH_MPSAFE; 435 if (flags & INTR_ENTROPY) 436 ih->ih_flags |= IH_ENTROPY; 437 438 /* We can only have one exclusive handler in a event. */ 439 mtx_lock(&ie->ie_lock); 440 if (!TAILQ_EMPTY(&ie->ie_handlers)) { 441 if ((flags & INTR_EXCL) || 442 (TAILQ_FIRST(&ie->ie_handlers)->ih_flags & IH_EXCLUSIVE)) { 443 mtx_unlock(&ie->ie_lock); 444 free(ih, M_ITHREAD); 445 return (EINVAL); 446 } 447 } 448 449 /* Add the new handler to the event in priority order. */ 450 TAILQ_FOREACH(temp_ih, &ie->ie_handlers, ih_next) { 451 if (temp_ih->ih_pri > ih->ih_pri) 452 break; 453 } 454 if (temp_ih == NULL) 455 TAILQ_INSERT_TAIL(&ie->ie_handlers, ih, ih_next); 456 else 457 TAILQ_INSERT_BEFORE(temp_ih, ih, ih_next); 458 intr_event_update(ie); 459 460 /* Create a thread if we need one. */ 461 while (ie->ie_thread == NULL && handler != NULL) { 462 if (ie->ie_flags & IE_ADDING_THREAD) 463 msleep(ie, &ie->ie_lock, 0, "ithread", 0); 464 else { 465 ie->ie_flags |= IE_ADDING_THREAD; 466 mtx_unlock(&ie->ie_lock); 467 it = ithread_create("intr: newborn"); 468 mtx_lock(&ie->ie_lock); 469 ie->ie_flags &= ~IE_ADDING_THREAD; 470 ie->ie_thread = it; 471 it->it_event = ie; 472 ithread_update(it); 473 wakeup(ie); 474 } 475 } 476 CTR3(KTR_INTR, "%s: added %s to %s", __func__, ih->ih_name, 477 ie->ie_name); 478 mtx_unlock(&ie->ie_lock); 479 480 if (cookiep != NULL) 481 *cookiep = ih; 482 return (0); 483} 484#else 485int 486intr_event_add_handler(struct intr_event *ie, const char *name, 487 driver_filter_t filter, driver_intr_t handler, void *arg, u_char pri, 488 enum intr_type flags, void **cookiep) 489{ 490 struct intr_handler *ih, *temp_ih; 491 struct intr_thread *it; 492 493 if (ie == NULL || name == NULL || (handler == NULL && filter == NULL)) 494 return (EINVAL); 495 496 /* Allocate and populate an interrupt handler structure. */ 497 ih = malloc(sizeof(struct intr_handler), M_ITHREAD, M_WAITOK | M_ZERO); 498 ih->ih_filter = filter; 499 ih->ih_handler = handler; 500 ih->ih_argument = arg; 501 ih->ih_name = name; 502 ih->ih_event = ie; 503 ih->ih_pri = pri; 504 if (flags & INTR_EXCL) 505 ih->ih_flags = IH_EXCLUSIVE; 506 if (flags & INTR_MPSAFE) 507 ih->ih_flags |= IH_MPSAFE; 508 if (flags & INTR_ENTROPY) 509 ih->ih_flags |= IH_ENTROPY; 510 511 /* We can only have one exclusive handler in a event. */ 512 mtx_lock(&ie->ie_lock); 513 if (!TAILQ_EMPTY(&ie->ie_handlers)) { 514 if ((flags & INTR_EXCL) || 515 (TAILQ_FIRST(&ie->ie_handlers)->ih_flags & IH_EXCLUSIVE)) { 516 mtx_unlock(&ie->ie_lock); 517 free(ih, M_ITHREAD); 518 return (EINVAL); 519 } 520 } 521 522 /* Add the new handler to the event in priority order. */ 523 TAILQ_FOREACH(temp_ih, &ie->ie_handlers, ih_next) { 524 if (temp_ih->ih_pri > ih->ih_pri) 525 break; 526 } 527 if (temp_ih == NULL) 528 TAILQ_INSERT_TAIL(&ie->ie_handlers, ih, ih_next); 529 else 530 TAILQ_INSERT_BEFORE(temp_ih, ih, ih_next); 531 intr_event_update(ie); 532 533 /* For filtered handlers, create a private ithread to run on. */ 534 if (filter != NULL && handler != NULL) { 535 mtx_unlock(&ie->ie_lock); 536 it = ithread_create("intr: newborn", ih); 537 mtx_lock(&ie->ie_lock); 538 it->it_event = ie; 539 ih->ih_thread = it; 540 ithread_update(it); // XXX - do we really need this?!?!? 541 } else { /* Create the global per-event thread if we need one. */ 542 while (ie->ie_thread == NULL && handler != NULL) { 543 if (ie->ie_flags & IE_ADDING_THREAD) 544 msleep(ie, &ie->ie_lock, 0, "ithread", 0); 545 else { 546 ie->ie_flags |= IE_ADDING_THREAD; 547 mtx_unlock(&ie->ie_lock); 548 it = ithread_create("intr: newborn", ih); 549 mtx_lock(&ie->ie_lock); 550 ie->ie_flags &= ~IE_ADDING_THREAD; 551 ie->ie_thread = it; 552 it->it_event = ie; 553 ithread_update(it); 554 wakeup(ie); 555 } 556 } 557 } 558 CTR3(KTR_INTR, "%s: added %s to %s", __func__, ih->ih_name, 559 ie->ie_name); 560 mtx_unlock(&ie->ie_lock); 561 562 if (cookiep != NULL) 563 *cookiep = ih; 564 return (0); 565} 566#endif 567 568/* 569 * Return the ie_source field from the intr_event an intr_handler is 570 * associated with. 571 */ 572void * 573intr_handler_source(void *cookie) 574{ 575 struct intr_handler *ih; 576 struct intr_event *ie; 577 578 ih = (struct intr_handler *)cookie; 579 if (ih == NULL) 580 return (NULL); 581 ie = ih->ih_event; 582 KASSERT(ie != NULL, 583 ("interrupt handler \"%s\" has a NULL interrupt event", 584 ih->ih_name)); 585 return (ie->ie_source); 586} 587 588#ifndef INTR_FILTER 589int 590intr_event_remove_handler(void *cookie) 591{ 592 struct intr_handler *handler = (struct intr_handler *)cookie; 593 struct intr_event *ie; 594#ifdef INVARIANTS 595 struct intr_handler *ih; 596#endif 597#ifdef notyet 598 int dead; 599#endif 600 601 if (handler == NULL) 602 return (EINVAL); 603 ie = handler->ih_event; 604 KASSERT(ie != NULL, 605 ("interrupt handler \"%s\" has a NULL interrupt event", 606 handler->ih_name)); 607 mtx_lock(&ie->ie_lock); 608 CTR3(KTR_INTR, "%s: removing %s from %s", __func__, handler->ih_name, 609 ie->ie_name); 610#ifdef INVARIANTS 611 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) 612 if (ih == handler) 613 goto ok; 614 mtx_unlock(&ie->ie_lock); 615 panic("interrupt handler \"%s\" not found in interrupt event \"%s\"", 616 ih->ih_name, ie->ie_name); 617ok: 618#endif 619 /* 620 * If there is no ithread, then just remove the handler and return. 621 * XXX: Note that an INTR_FAST handler might be running on another 622 * CPU! 623 */ 624 if (ie->ie_thread == NULL) { 625 TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next); 626 mtx_unlock(&ie->ie_lock); 627 free(handler, M_ITHREAD); 628 return (0); 629 } 630 631 /* 632 * If the interrupt thread is already running, then just mark this 633 * handler as being dead and let the ithread do the actual removal. 634 * 635 * During a cold boot while cold is set, msleep() does not sleep, 636 * so we have to remove the handler here rather than letting the 637 * thread do it. 638 */ 639 thread_lock(ie->ie_thread->it_thread); 640 if (!TD_AWAITING_INTR(ie->ie_thread->it_thread) && !cold) { 641 handler->ih_flags |= IH_DEAD; 642 643 /* 644 * Ensure that the thread will process the handler list 645 * again and remove this handler if it has already passed 646 * it on the list. 647 */ 648 ie->ie_thread->it_need = 1; 649 } else 650 TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next); 651 thread_unlock(ie->ie_thread->it_thread); 652 while (handler->ih_flags & IH_DEAD) 653 msleep(handler, &ie->ie_lock, 0, "iev_rmh", 0); 654 intr_event_update(ie); 655#ifdef notyet 656 /* 657 * XXX: This could be bad in the case of ppbus(8). Also, I think 658 * this could lead to races of stale data when servicing an 659 * interrupt. 660 */ 661 dead = 1; 662 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) { 663 if (!(ih->ih_flags & IH_FAST)) { 664 dead = 0; 665 break; 666 } 667 } 668 if (dead) { 669 ithread_destroy(ie->ie_thread); 670 ie->ie_thread = NULL; 671 } 672#endif 673 mtx_unlock(&ie->ie_lock); 674 free(handler, M_ITHREAD); 675 return (0); 676} 677 678int 679intr_event_schedule_thread(struct intr_event *ie) 680{ 681 struct intr_entropy entropy; 682 struct intr_thread *it; 683 struct thread *td; 684 struct thread *ctd; 685 struct proc *p; 686 687 /* 688 * If no ithread or no handlers, then we have a stray interrupt. 689 */ 690 if (ie == NULL || TAILQ_EMPTY(&ie->ie_handlers) || 691 ie->ie_thread == NULL) 692 return (EINVAL); 693 694 ctd = curthread; 695 it = ie->ie_thread; 696 td = it->it_thread; 697 p = td->td_proc; 698 699 /* 700 * If any of the handlers for this ithread claim to be good 701 * sources of entropy, then gather some. 702 */ 703 if (harvest.interrupt && ie->ie_flags & IE_ENTROPY) { 704 CTR3(KTR_INTR, "%s: pid %d (%s) gathering entropy", __func__, 705 p->p_pid, td->td_name); 706 entropy.event = (uintptr_t)ie; 707 entropy.td = ctd; 708 random_harvest(&entropy, sizeof(entropy), 2, 0, 709 RANDOM_INTERRUPT); 710 } 711 712 KASSERT(p != NULL, ("ithread %s has no process", ie->ie_name)); 713 714 /* 715 * Set it_need to tell the thread to keep running if it is already 716 * running. Then, lock the thread and see if we actually need to 717 * put it on the runqueue. 718 */ 719 it->it_need = 1; 720 thread_lock(td); 721 if (TD_AWAITING_INTR(td)) { 722 CTR3(KTR_INTR, "%s: schedule pid %d (%s)", __func__, p->p_pid, 723 td->td_name); 724 TD_CLR_IWAIT(td); 725 sched_add(td, SRQ_INTR); 726 } else { 727 CTR5(KTR_INTR, "%s: pid %d (%s): it_need %d, state %d", 728 __func__, p->p_pid, td->td_name, it->it_need, td->td_state); 729 } 730 thread_unlock(td); 731 732 return (0); 733} 734#else 735int 736intr_event_remove_handler(void *cookie) 737{ 738 struct intr_handler *handler = (struct intr_handler *)cookie; 739 struct intr_event *ie; 740 struct intr_thread *it; 741#ifdef INVARIANTS 742 struct intr_handler *ih; 743#endif 744#ifdef notyet 745 int dead; 746#endif 747 748 if (handler == NULL) 749 return (EINVAL); 750 ie = handler->ih_event; 751 KASSERT(ie != NULL, 752 ("interrupt handler \"%s\" has a NULL interrupt event", 753 handler->ih_name)); 754 mtx_lock(&ie->ie_lock); 755 CTR3(KTR_INTR, "%s: removing %s from %s", __func__, handler->ih_name, 756 ie->ie_name); 757#ifdef INVARIANTS 758 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) 759 if (ih == handler) 760 goto ok; 761 mtx_unlock(&ie->ie_lock); 762 panic("interrupt handler \"%s\" not found in interrupt event \"%s\"", 763 ih->ih_name, ie->ie_name); 764ok: 765#endif 766 /* 767 * If there are no ithreads (per event and per handler), then 768 * just remove the handler and return. 769 * XXX: Note that an INTR_FAST handler might be running on another CPU! 770 */ 771 if (ie->ie_thread == NULL && handler->ih_thread == NULL) { 772 TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next); 773 mtx_unlock(&ie->ie_lock); 774 free(handler, M_ITHREAD); 775 return (0); 776 } 777 778 /* Private or global ithread? */ 779 it = (handler->ih_thread) ? handler->ih_thread : ie->ie_thread; 780 /* 781 * If the interrupt thread is already running, then just mark this 782 * handler as being dead and let the ithread do the actual removal. 783 * 784 * During a cold boot while cold is set, msleep() does not sleep, 785 * so we have to remove the handler here rather than letting the 786 * thread do it. 787 */ 788 thread_lock(it->it_thread); 789 if (!TD_AWAITING_INTR(it->it_thread) && !cold) { 790 handler->ih_flags |= IH_DEAD; 791 792 /* 793 * Ensure that the thread will process the handler list 794 * again and remove this handler if it has already passed 795 * it on the list. 796 */ 797 it->it_need = 1; 798 } else 799 TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next); 800 thread_unlock(it->it_thread); 801 while (handler->ih_flags & IH_DEAD) 802 msleep(handler, &ie->ie_lock, 0, "iev_rmh", 0); 803 /* 804 * At this point, the handler has been disconnected from the event, 805 * so we can kill the private ithread if any. 806 */ 807 if (handler->ih_thread) { 808 ithread_destroy(handler->ih_thread); 809 handler->ih_thread = NULL; 810 } 811 intr_event_update(ie); 812#ifdef notyet 813 /* 814 * XXX: This could be bad in the case of ppbus(8). Also, I think 815 * this could lead to races of stale data when servicing an 816 * interrupt. 817 */ 818 dead = 1; 819 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) { 820 if (handler != NULL) { 821 dead = 0; 822 break; 823 } 824 } 825 if (dead) { 826 ithread_destroy(ie->ie_thread); 827 ie->ie_thread = NULL; 828 } 829#endif 830 mtx_unlock(&ie->ie_lock); 831 free(handler, M_ITHREAD); 832 return (0); 833} 834 835int 836intr_event_schedule_thread(struct intr_event *ie, struct intr_thread *it) 837{ 838 struct intr_entropy entropy; 839 struct thread *td; 840 struct thread *ctd; 841 struct proc *p; 842 843 /* 844 * If no ithread or no handlers, then we have a stray interrupt. 845 */ 846 if (ie == NULL || TAILQ_EMPTY(&ie->ie_handlers) || it == NULL) 847 return (EINVAL); 848 849 ctd = curthread; 850 td = it->it_thread; 851 p = td->td_proc; 852 853 /* 854 * If any of the handlers for this ithread claim to be good 855 * sources of entropy, then gather some. 856 */ 857 if (harvest.interrupt && ie->ie_flags & IE_ENTROPY) { 858 CTR3(KTR_INTR, "%s: pid %d (%s) gathering entropy", __func__, 859 p->p_pid, td->td_name); 860 entropy.event = (uintptr_t)ie; 861 entropy.td = ctd; 862 random_harvest(&entropy, sizeof(entropy), 2, 0, 863 RANDOM_INTERRUPT); 864 } 865 866 KASSERT(p != NULL, ("ithread %s has no process", ie->ie_name)); 867 868 /* 869 * Set it_need to tell the thread to keep running if it is already 870 * running. Then, lock the thread and see if we actually need to 871 * put it on the runqueue. 872 */ 873 it->it_need = 1; 874 thread_lock(td); 875 if (TD_AWAITING_INTR(td)) { 876 CTR3(KTR_INTR, "%s: schedule pid %d (%s)", __func__, p->p_pid, 877 td->td_name); 878 TD_CLR_IWAIT(td); 879 sched_add(td, SRQ_INTR); 880 } else { 881 CTR5(KTR_INTR, "%s: pid %d (%s): it_need %d, state %d", 882 __func__, p->p_pid, td->td_name, it->it_need, td->td_state); 883 } 884 thread_unlock(td); 885 886 return (0); 887} 888#endif 889 890/* 891 * Add a software interrupt handler to a specified event. If a given event 892 * is not specified, then a new event is created. 893 */ 894int 895swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler, 896 void *arg, int pri, enum intr_type flags, void **cookiep) 897{ 898 struct intr_event *ie; 899 int error; 900 901 if (flags & INTR_ENTROPY) 902 return (EINVAL); 903 904 ie = (eventp != NULL) ? *eventp : NULL; 905 906 if (ie != NULL) { 907 if (!(ie->ie_flags & IE_SOFT)) 908 return (EINVAL); 909 } else { 910 error = intr_event_create(&ie, NULL, IE_SOFT, 911 NULL, NULL, NULL, NULL, "swi%d:", pri); 912 if (error) 913 return (error); 914 if (eventp != NULL) 915 *eventp = ie; 916 } 917 error = intr_event_add_handler(ie, name, NULL, handler, arg, 918 (pri * RQ_PPQ) + PI_SOFT, flags, cookiep); 919 if (error) 920 return (error); 921 if (pri == SWI_CLOCK) { 922 struct proc *p; 923 p = ie->ie_thread->it_thread->td_proc; 924 PROC_LOCK(p); 925 p->p_flag |= P_NOLOAD; 926 PROC_UNLOCK(p); 927 } 928 return (0); 929} 930 931/* 932 * Schedule a software interrupt thread. 933 */ 934void 935swi_sched(void *cookie, int flags) 936{ 937 struct intr_handler *ih = (struct intr_handler *)cookie; 938 struct intr_event *ie = ih->ih_event; 939 int error; 940 941 CTR3(KTR_INTR, "swi_sched: %s %s need=%d", ie->ie_name, ih->ih_name, 942 ih->ih_need); 943 944 /* 945 * Set ih_need for this handler so that if the ithread is already 946 * running it will execute this handler on the next pass. Otherwise, 947 * it will execute it the next time it runs. 948 */ 949 atomic_store_rel_int(&ih->ih_need, 1); 950 951 if (!(flags & SWI_DELAY)) { 952 PCPU_INC(cnt.v_soft); 953#ifdef INTR_FILTER 954 error = intr_event_schedule_thread(ie, ie->ie_thread); 955#else 956 error = intr_event_schedule_thread(ie); 957#endif 958 KASSERT(error == 0, ("stray software interrupt")); 959 } 960} 961 962/* 963 * Remove a software interrupt handler. Currently this code does not 964 * remove the associated interrupt event if it becomes empty. Calling code 965 * may do so manually via intr_event_destroy(), but that's not really 966 * an optimal interface. 967 */ 968int 969swi_remove(void *cookie) 970{ 971 972 return (intr_event_remove_handler(cookie)); 973} 974 975#ifdef INTR_FILTER 976static void 977priv_ithread_execute_handler(struct proc *p, struct intr_handler *ih) 978{ 979 struct intr_event *ie; 980 981 ie = ih->ih_event; 982 /* 983 * If this handler is marked for death, remove it from 984 * the list of handlers and wake up the sleeper. 985 */ 986 if (ih->ih_flags & IH_DEAD) { 987 mtx_lock(&ie->ie_lock); 988 TAILQ_REMOVE(&ie->ie_handlers, ih, ih_next); 989 ih->ih_flags &= ~IH_DEAD; 990 wakeup(ih); 991 mtx_unlock(&ie->ie_lock); 992 return; 993 } 994 995 /* Execute this handler. */ 996 CTR6(KTR_INTR, "%s: pid %d exec %p(%p) for %s flg=%x", 997 __func__, p->p_pid, (void *)ih->ih_handler, ih->ih_argument, 998 ih->ih_name, ih->ih_flags); 999 1000 if (!(ih->ih_flags & IH_MPSAFE)) 1001 mtx_lock(&Giant); 1002 ih->ih_handler(ih->ih_argument); 1003 if (!(ih->ih_flags & IH_MPSAFE)) 1004 mtx_unlock(&Giant); 1005} 1006#endif 1007 1008static void 1009ithread_execute_handlers(struct proc *p, struct intr_event *ie) 1010{ 1011 struct intr_handler *ih, *ihn; 1012 1013 /* Interrupt handlers should not sleep. */ 1014 if (!(ie->ie_flags & IE_SOFT)) 1015 THREAD_NO_SLEEPING(); 1016 TAILQ_FOREACH_SAFE(ih, &ie->ie_handlers, ih_next, ihn) { 1017 1018 /* 1019 * If this handler is marked for death, remove it from 1020 * the list of handlers and wake up the sleeper. 1021 */ 1022 if (ih->ih_flags & IH_DEAD) { 1023 mtx_lock(&ie->ie_lock); 1024 TAILQ_REMOVE(&ie->ie_handlers, ih, ih_next); 1025 ih->ih_flags &= ~IH_DEAD; 1026 wakeup(ih); 1027 mtx_unlock(&ie->ie_lock); 1028 continue; 1029 } 1030 1031 /* Skip filter only handlers */ 1032 if (ih->ih_handler == NULL) 1033 continue; 1034 1035 /* 1036 * For software interrupt threads, we only execute 1037 * handlers that have their need flag set. Hardware 1038 * interrupt threads always invoke all of their handlers. 1039 */ 1040 if (ie->ie_flags & IE_SOFT) { 1041 if (!ih->ih_need) 1042 continue; 1043 else 1044 atomic_store_rel_int(&ih->ih_need, 0); 1045 } 1046 1047 /* Execute this handler. */ 1048 CTR6(KTR_INTR, "%s: pid %d exec %p(%p) for %s flg=%x", 1049 __func__, p->p_pid, (void *)ih->ih_handler, 1050 ih->ih_argument, ih->ih_name, ih->ih_flags); 1051 1052 if (!(ih->ih_flags & IH_MPSAFE)) 1053 mtx_lock(&Giant); 1054 ih->ih_handler(ih->ih_argument); 1055 if (!(ih->ih_flags & IH_MPSAFE)) 1056 mtx_unlock(&Giant); 1057 } 1058 if (!(ie->ie_flags & IE_SOFT)) 1059 THREAD_SLEEPING_OK(); 1060 1061 /* 1062 * Interrupt storm handling: 1063 * 1064 * If this interrupt source is currently storming, then throttle 1065 * it to only fire the handler once per clock tick. 1066 * 1067 * If this interrupt source is not currently storming, but the 1068 * number of back to back interrupts exceeds the storm threshold, 1069 * then enter storming mode. 1070 */ 1071 if (intr_storm_threshold != 0 && ie->ie_count >= intr_storm_threshold && 1072 !(ie->ie_flags & IE_SOFT)) { 1073 /* Report the message only once every second. */ 1074 if (ppsratecheck(&ie->ie_warntm, &ie->ie_warncnt, 1)) { 1075 printf( 1076 "interrupt storm detected on \"%s\"; throttling interrupt source\n", 1077 ie->ie_name); 1078 } 1079 pause("istorm", 1); 1080 } else 1081 ie->ie_count++; 1082 1083 /* 1084 * Now that all the handlers have had a chance to run, reenable 1085 * the interrupt source. 1086 */ 1087 if (ie->ie_enable != NULL) 1088 ie->ie_enable(ie->ie_source); 1089} 1090 1091#ifndef INTR_FILTER 1092/* 1093 * This is the main code for interrupt threads. 1094 */ 1095static void 1096ithread_loop(void *arg) 1097{ 1098 struct intr_thread *ithd; 1099 struct intr_event *ie; 1100 struct thread *td; 1101 struct proc *p; 1102 u_char cpu; 1103 1104 td = curthread; 1105 p = td->td_proc; 1106 ithd = (struct intr_thread *)arg; 1107 KASSERT(ithd->it_thread == td, 1108 ("%s: ithread and proc linkage out of sync", __func__)); 1109 ie = ithd->it_event; 1110 ie->ie_count = 0; 1111 cpu = NOCPU; 1112 1113 /* 1114 * As long as we have interrupts outstanding, go through the 1115 * list of handlers, giving each one a go at it. 1116 */ 1117 for (;;) { 1118 /* 1119 * If we are an orphaned thread, then just die. 1120 */ 1121 if (ithd->it_flags & IT_DEAD) { 1122 CTR3(KTR_INTR, "%s: pid %d (%s) exiting", __func__, 1123 p->p_pid, td->td_name); 1124 free(ithd, M_ITHREAD); 1125 kthread_exit(); 1126 } 1127 1128 /* 1129 * Service interrupts. If another interrupt arrives while 1130 * we are running, it will set it_need to note that we 1131 * should make another pass. 1132 */ 1133 while (ithd->it_need) { 1134 /* 1135 * This might need a full read and write barrier 1136 * to make sure that this write posts before any 1137 * of the memory or device accesses in the 1138 * handlers. 1139 */ 1140 atomic_store_rel_int(&ithd->it_need, 0); 1141 ithread_execute_handlers(p, ie); 1142 } 1143 WITNESS_WARN(WARN_PANIC, NULL, "suspending ithread"); 1144 mtx_assert(&Giant, MA_NOTOWNED); 1145 1146 /* 1147 * Processed all our interrupts. Now get the sched 1148 * lock. This may take a while and it_need may get 1149 * set again, so we have to check it again. 1150 */ 1151 thread_lock(td); 1152 if (!ithd->it_need && !(ithd->it_flags & IT_DEAD)) { 1153 TD_SET_IWAIT(td); 1154 ie->ie_count = 0; 1155 mi_switch(SW_VOL, NULL); 1156 } 1157 1158#ifdef SMP 1159 /* 1160 * Ensure we are bound to the correct CPU. We can't 1161 * move ithreads until SMP is running however, so just 1162 * leave interrupts on the boor CPU during boot. 1163 */ 1164 if (ie->ie_cpu != cpu && smp_started) { 1165 cpu = ie->ie_cpu; 1166 if (cpu == NOCPU) 1167 sched_unbind(td); 1168 else 1169 sched_bind(td, cpu); 1170 } 1171#endif 1172 thread_unlock(td); 1173 } 1174} 1175#else 1176/* 1177 * This is the main code for interrupt threads. 1178 */ 1179static void 1180ithread_loop(void *arg) 1181{ 1182 struct intr_thread *ithd; 1183 struct intr_handler *ih; 1184 struct intr_event *ie; 1185 struct thread *td; 1186 struct proc *p; 1187 int priv; 1188 u_char cpu; 1189 1190 td = curthread; 1191 p = td->td_proc; 1192 ih = (struct intr_handler *)arg; 1193 priv = (ih->ih_thread != NULL) ? 1 : 0; 1194 ithd = (priv) ? ih->ih_thread : ih->ih_event->ie_thread; 1195 KASSERT(ithd->it_thread == td, 1196 ("%s: ithread and proc linkage out of sync", __func__)); 1197 ie = ithd->it_event; 1198 ie->ie_count = 0; 1199 cpu = NOCPU; 1200 1201 /* 1202 * As long as we have interrupts outstanding, go through the 1203 * list of handlers, giving each one a go at it. 1204 */ 1205 for (;;) { 1206 /* 1207 * If we are an orphaned thread, then just die. 1208 */ 1209 if (ithd->it_flags & IT_DEAD) { 1210 CTR3(KTR_INTR, "%s: pid %d (%s) exiting", __func__, 1211 p->p_pid, td->td_name); 1212 free(ithd, M_ITHREAD); 1213 kthread_exit(); 1214 } 1215 1216 /* 1217 * Service interrupts. If another interrupt arrives while 1218 * we are running, it will set it_need to note that we 1219 * should make another pass. 1220 */ 1221 while (ithd->it_need) { 1222 /* 1223 * This might need a full read and write barrier 1224 * to make sure that this write posts before any 1225 * of the memory or device accesses in the 1226 * handlers. 1227 */ 1228 atomic_store_rel_int(&ithd->it_need, 0); 1229 if (priv) 1230 priv_ithread_execute_handler(p, ih); 1231 else 1232 ithread_execute_handlers(p, ie); 1233 } 1234 WITNESS_WARN(WARN_PANIC, NULL, "suspending ithread"); 1235 mtx_assert(&Giant, MA_NOTOWNED); 1236 1237 /* 1238 * Processed all our interrupts. Now get the sched 1239 * lock. This may take a while and it_need may get 1240 * set again, so we have to check it again. 1241 */ 1242 thread_lock(td); 1243 if (!ithd->it_need && !(ithd->it_flags & IT_DEAD)) { 1244 TD_SET_IWAIT(td); 1245 ie->ie_count = 0; 1246 mi_switch(SW_VOL, NULL); 1247 } 1248 1249#ifdef SMP 1250 /* 1251 * Ensure we are bound to the correct CPU. We can't 1252 * move ithreads until SMP is running however, so just 1253 * leave interrupts on the boor CPU during boot. 1254 */ 1255 if (!priv && ie->ie_cpu != cpu && smp_started) { 1256 cpu = ie->ie_cpu; 1257 if (cpu == NOCPU) 1258 sched_unbind(td); 1259 else 1260 sched_bind(td, cpu); 1261 } 1262#endif 1263 thread_unlock(td); 1264 } 1265} 1266 1267/* 1268 * Main loop for interrupt filter. 1269 * 1270 * Some architectures (i386, amd64 and arm) require the optional frame 1271 * parameter, and use it as the main argument for fast handler execution 1272 * when ih_argument == NULL. 1273 * 1274 * Return value: 1275 * o FILTER_STRAY: No filter recognized the event, and no 1276 * filter-less handler is registered on this 1277 * line. 1278 * o FILTER_HANDLED: A filter claimed the event and served it. 1279 * o FILTER_SCHEDULE_THREAD: No filter claimed the event, but there's at 1280 * least one filter-less handler on this line. 1281 * o FILTER_HANDLED | 1282 * FILTER_SCHEDULE_THREAD: A filter claimed the event, and asked for 1283 * scheduling the per-handler ithread. 1284 * 1285 * In case an ithread has to be scheduled, in *ithd there will be a 1286 * pointer to a struct intr_thread containing the thread to be 1287 * scheduled. 1288 */ 1289 1290int 1291intr_filter_loop(struct intr_event *ie, struct trapframe *frame, 1292 struct intr_thread **ithd) 1293{ 1294 struct intr_handler *ih; 1295 void *arg; 1296 int ret, thread_only; 1297 1298 ret = 0; 1299 thread_only = 0; 1300 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) { 1301 /* 1302 * Execute fast interrupt handlers directly. 1303 * To support clock handlers, if a handler registers 1304 * with a NULL argument, then we pass it a pointer to 1305 * a trapframe as its argument. 1306 */ 1307 arg = ((ih->ih_argument == NULL) ? frame : ih->ih_argument); 1308 1309 CTR5(KTR_INTR, "%s: exec %p/%p(%p) for %s", __func__, 1310 ih->ih_filter, ih->ih_handler, arg, ih->ih_name); 1311 1312 if (ih->ih_filter != NULL) 1313 ret = ih->ih_filter(arg); 1314 else { 1315 thread_only = 1; 1316 continue; 1317 } 1318 1319 if (ret & FILTER_STRAY) 1320 continue; 1321 else { 1322 *ithd = ih->ih_thread; 1323 return (ret); 1324 } 1325 } 1326 1327 /* 1328 * No filters handled the interrupt and we have at least 1329 * one handler without a filter. In this case, we schedule 1330 * all of the filter-less handlers to run in the ithread. 1331 */ 1332 if (thread_only) { 1333 *ithd = ie->ie_thread; 1334 return (FILTER_SCHEDULE_THREAD); 1335 } 1336 return (FILTER_STRAY); 1337} 1338 1339/* 1340 * Main interrupt handling body. 1341 * 1342 * Input: 1343 * o ie: the event connected to this interrupt. 1344 * o frame: some archs (i.e. i386) pass a frame to some. 1345 * handlers as their main argument. 1346 * Return value: 1347 * o 0: everything ok. 1348 * o EINVAL: stray interrupt. 1349 */ 1350int 1351intr_event_handle(struct intr_event *ie, struct trapframe *frame) 1352{ 1353 struct intr_thread *ithd; 1354 struct thread *td; 1355 int thread; 1356 1357 ithd = NULL; 1358 td = curthread; 1359 1360 if (ie == NULL || TAILQ_EMPTY(&ie->ie_handlers)) 1361 return (EINVAL); 1362 1363 td->td_intr_nesting_level++; 1364 thread = 0; 1365 critical_enter(); 1366 thread = intr_filter_loop(ie, frame, &ithd); 1367 1368 /* 1369 * If the interrupt was fully served, send it an EOI but leave 1370 * it unmasked. Otherwise, mask the source as well as sending 1371 * it an EOI. 1372 */ 1373 if (thread & FILTER_HANDLED) { 1374 if (ie->ie_eoi != NULL) 1375 ie->ie_eoi(ie->ie_source); 1376 } else { 1377 if (ie->ie_disable != NULL) 1378 ie->ie_disable(ie->ie_source); 1379 } 1380 critical_exit(); 1381 1382 /* Interrupt storm logic */ 1383 if (thread & FILTER_STRAY) { 1384 ie->ie_count++; 1385 if (ie->ie_count < intr_storm_threshold) 1386 printf("Interrupt stray detection not present\n"); 1387 } 1388 1389 /* Schedule an ithread if needed. */ 1390 if (thread & FILTER_SCHEDULE_THREAD) { 1391 if (intr_event_schedule_thread(ie, ithd) != 0) 1392 panic("%s: impossible stray interrupt", __func__); 1393 } 1394 td->td_intr_nesting_level--; 1395 return (0); 1396} 1397#endif 1398 1399#ifdef DDB 1400/* 1401 * Dump details about an interrupt handler 1402 */ 1403static void 1404db_dump_intrhand(struct intr_handler *ih) 1405{ 1406 int comma; 1407 1408 db_printf("\t%-10s ", ih->ih_name); 1409 switch (ih->ih_pri) { 1410 case PI_REALTIME: 1411 db_printf("CLK "); 1412 break; 1413 case PI_AV: 1414 db_printf("AV "); 1415 break; 1416 case PI_TTYHIGH: 1417 case PI_TTYLOW: 1418 db_printf("TTY "); 1419 break; 1420 case PI_TAPE: 1421 db_printf("TAPE"); 1422 break; 1423 case PI_NET: 1424 db_printf("NET "); 1425 break; 1426 case PI_DISK: 1427 case PI_DISKLOW: 1428 db_printf("DISK"); 1429 break; 1430 case PI_DULL: 1431 db_printf("DULL"); 1432 break; 1433 default: 1434 if (ih->ih_pri >= PI_SOFT) 1435 db_printf("SWI "); 1436 else 1437 db_printf("%4u", ih->ih_pri); 1438 break; 1439 } 1440 db_printf(" "); 1441 db_printsym((uintptr_t)ih->ih_handler, DB_STGY_PROC); 1442 db_printf("(%p)", ih->ih_argument); 1443 if (ih->ih_need || 1444 (ih->ih_flags & (IH_EXCLUSIVE | IH_ENTROPY | IH_DEAD | 1445 IH_MPSAFE)) != 0) { 1446 db_printf(" {"); 1447 comma = 0; 1448 if (ih->ih_flags & IH_EXCLUSIVE) { 1449 if (comma) 1450 db_printf(", "); 1451 db_printf("EXCL"); 1452 comma = 1; 1453 } 1454 if (ih->ih_flags & IH_ENTROPY) { 1455 if (comma) 1456 db_printf(", "); 1457 db_printf("ENTROPY"); 1458 comma = 1; 1459 } 1460 if (ih->ih_flags & IH_DEAD) { 1461 if (comma) 1462 db_printf(", "); 1463 db_printf("DEAD"); 1464 comma = 1; 1465 } 1466 if (ih->ih_flags & IH_MPSAFE) { 1467 if (comma) 1468 db_printf(", "); 1469 db_printf("MPSAFE"); 1470 comma = 1; 1471 } 1472 if (ih->ih_need) { 1473 if (comma) 1474 db_printf(", "); 1475 db_printf("NEED"); 1476 } 1477 db_printf("}"); 1478 } 1479 db_printf("\n"); 1480} 1481 1482/* 1483 * Dump details about a event. 1484 */ 1485void 1486db_dump_intr_event(struct intr_event *ie, int handlers) 1487{ 1488 struct intr_handler *ih; 1489 struct intr_thread *it; 1490 int comma; 1491 1492 db_printf("%s ", ie->ie_fullname); 1493 it = ie->ie_thread; 1494 if (it != NULL) 1495 db_printf("(pid %d)", it->it_thread->td_proc->p_pid); 1496 else 1497 db_printf("(no thread)"); 1498 if (ie->ie_cpu != NOCPU) 1499 db_printf(" (CPU %d)", ie->ie_cpu); 1500 if ((ie->ie_flags & (IE_SOFT | IE_ENTROPY | IE_ADDING_THREAD)) != 0 || 1501 (it != NULL && it->it_need)) { 1502 db_printf(" {"); 1503 comma = 0; 1504 if (ie->ie_flags & IE_SOFT) { 1505 db_printf("SOFT"); 1506 comma = 1; 1507 } 1508 if (ie->ie_flags & IE_ENTROPY) { 1509 if (comma) 1510 db_printf(", "); 1511 db_printf("ENTROPY"); 1512 comma = 1; 1513 } 1514 if (ie->ie_flags & IE_ADDING_THREAD) { 1515 if (comma) 1516 db_printf(", "); 1517 db_printf("ADDING_THREAD"); 1518 comma = 1; 1519 } 1520 if (it != NULL && it->it_need) { 1521 if (comma) 1522 db_printf(", "); 1523 db_printf("NEED"); 1524 } 1525 db_printf("}"); 1526 } 1527 db_printf("\n"); 1528 1529 if (handlers) 1530 TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) 1531 db_dump_intrhand(ih); 1532} 1533 1534/* 1535 * Dump data about interrupt handlers 1536 */ 1537DB_SHOW_COMMAND(intr, db_show_intr) 1538{ 1539 struct intr_event *ie; 1540 int all, verbose; 1541 1542 verbose = index(modif, 'v') != NULL; 1543 all = index(modif, 'a') != NULL; 1544 TAILQ_FOREACH(ie, &event_list, ie_list) { 1545 if (!all && TAILQ_EMPTY(&ie->ie_handlers)) 1546 continue; 1547 db_dump_intr_event(ie, verbose); 1548 if (db_pager_quit) 1549 break; 1550 } 1551} 1552#endif /* DDB */ 1553 1554/* 1555 * Start standard software interrupt threads 1556 */ 1557static void 1558start_softintr(void *dummy) 1559{ 1560 1561 if (swi_add(NULL, "vm", swi_vm, NULL, SWI_VM, INTR_MPSAFE, &vm_ih)) 1562 panic("died while creating vm swi ithread"); 1563} 1564SYSINIT(start_softintr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_softintr, 1565 NULL); 1566 1567/* 1568 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt. 1569 * The data for this machine dependent, and the declarations are in machine 1570 * dependent code. The layout of intrnames and intrcnt however is machine 1571 * independent. 1572 * 1573 * We do not know the length of intrcnt and intrnames at compile time, so 1574 * calculate things at run time. 1575 */ 1576static int 1577sysctl_intrnames(SYSCTL_HANDLER_ARGS) 1578{ 1579 return (sysctl_handle_opaque(oidp, intrnames, eintrnames - intrnames, 1580 req)); 1581} 1582 1583SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD, 1584 NULL, 0, sysctl_intrnames, "", "Interrupt Names"); 1585 1586static int 1587sysctl_intrcnt(SYSCTL_HANDLER_ARGS) 1588{ 1589 return (sysctl_handle_opaque(oidp, intrcnt, 1590 (char *)eintrcnt - (char *)intrcnt, req)); 1591} 1592 1593SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD, 1594 NULL, 0, sysctl_intrcnt, "", "Interrupt Counts"); 1595 1596#ifdef DDB 1597/* 1598 * DDB command to dump the interrupt statistics. 1599 */ 1600DB_SHOW_COMMAND(intrcnt, db_show_intrcnt) 1601{ 1602 u_long *i; 1603 char *cp; 1604 1605 cp = intrnames; 1606 for (i = intrcnt; i != eintrcnt && !db_pager_quit; i++) { 1607 if (*cp == '\0') 1608 break; 1609 if (*i != 0) 1610 db_printf("%s\t%lu\n", cp, *i); 1611 cp += strlen(cp) + 1; 1612 } 1613} 1614#endif 1615