2 * Copyright (c) 2003 Matthew Dillon <dillon@backplane.com> All rights reserved.
3 * Copyright (c) 1997, Stefan Esser <se@freebsd.org> All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
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.
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.
26 * $FreeBSD: src/sys/kern/kern_intr.c,v 1.24.2.1 2001/10/14 20:05:50 luigi Exp $
27 * $DragonFly: src/sys/kern/kern_intr.c,v 1.55 2008/09/01 12:49:00 sephe Exp $
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/malloc.h>
34 #include <sys/kernel.h>
35 #include <sys/sysctl.h>
36 #include <sys/thread.h>
38 #include <sys/random.h>
39 #include <sys/serialize.h>
40 #include <sys/interrupt.h>
42 #include <sys/machintr.h>
44 #include <machine/frame.h>
46 #include <sys/interrupt.h>
48 #include <sys/thread2.h>
49 #include <sys/mplock2.h>
53 typedef struct intrec {
55 struct intr_info *info;
61 struct lwkt_serialize *serializer;
66 struct thread i_thread;
67 struct random_softc i_random;
69 long i_count; /* interrupts dispatched */
70 int i_mplock_required;
75 unsigned long i_straycount;
76 } intr_info_ary[MAX_INTS];
78 int max_installed_hard_intr;
79 int max_installed_soft_intr;
81 #define EMERGENCY_INTR_POLLING_FREQ_MAX 20000
84 * Assert that callers into interrupt handlers don't return with
85 * dangling tokens, spinlocks, or mp locks.
89 #define TD_INVARIANTS_DECLARE \
93 #define TD_INVARIANTS_GET(td) \
95 spincount = (td)->td_gd->gd_spinlocks_wr; \
96 curstop = (td)->td_toks_stop; \
99 #define TD_INVARIANTS_TEST(td, name) \
101 KASSERT(spincount == (td)->td_gd->gd_spinlocks_wr, \
102 ("spincount mismatch after interrupt handler %s", \
104 KASSERT(curstop == (td)->td_toks_stop, \
105 ("token count mismatch after interrupt handler %s", \
113 #define TD_INVARIANTS_DECLARE
114 #define TD_INVARIANTS_GET(td)
115 #define TD_INVARIANTS_TEST(td, name)
117 #endif /* ndef INVARIANTS */
119 static int sysctl_emergency_freq(SYSCTL_HANDLER_ARGS);
120 static int sysctl_emergency_enable(SYSCTL_HANDLER_ARGS);
121 static void emergency_intr_timer_callback(systimer_t, struct intrframe *);
122 static void ithread_handler(void *arg);
123 static void ithread_emergency(void *arg);
124 static void report_stray_interrupt(int intr, struct intr_info *info);
125 static void int_moveto_destcpu(int *, int *, int);
126 static void int_moveto_origcpu(int, int);
128 int intr_info_size = sizeof(intr_info_ary) / sizeof(intr_info_ary[0]);
130 static struct systimer emergency_intr_timer;
131 static struct thread emergency_intr_thread;
133 #define ISTATE_NOTHREAD 0
134 #define ISTATE_NORMAL 1
135 #define ISTATE_LIVELOCKED 2
137 static int livelock_limit = 40000;
138 static int livelock_lowater = 20000;
139 static int livelock_debug = -1;
140 SYSCTL_INT(_kern, OID_AUTO, livelock_limit,
141 CTLFLAG_RW, &livelock_limit, 0, "Livelock interrupt rate limit");
142 SYSCTL_INT(_kern, OID_AUTO, livelock_lowater,
143 CTLFLAG_RW, &livelock_lowater, 0, "Livelock low-water mark restore");
144 SYSCTL_INT(_kern, OID_AUTO, livelock_debug,
145 CTLFLAG_RW, &livelock_debug, 0, "Livelock debug intr#");
147 static int emergency_intr_enable = 0; /* emergency interrupt polling */
148 TUNABLE_INT("kern.emergency_intr_enable", &emergency_intr_enable);
149 SYSCTL_PROC(_kern, OID_AUTO, emergency_intr_enable, CTLTYPE_INT | CTLFLAG_RW,
150 0, 0, sysctl_emergency_enable, "I", "Emergency Interrupt Poll Enable");
152 static int emergency_intr_freq = 10; /* emergency polling frequency */
153 TUNABLE_INT("kern.emergency_intr_freq", &emergency_intr_freq);
154 SYSCTL_PROC(_kern, OID_AUTO, emergency_intr_freq, CTLTYPE_INT | CTLFLAG_RW,
155 0, 0, sysctl_emergency_freq, "I", "Emergency Interrupt Poll Frequency");
158 * Sysctl support routines
161 sysctl_emergency_enable(SYSCTL_HANDLER_ARGS)
165 enabled = emergency_intr_enable;
166 error = sysctl_handle_int(oidp, &enabled, 0, req);
167 if (error || req->newptr == NULL)
169 emergency_intr_enable = enabled;
170 if (emergency_intr_enable) {
171 systimer_adjust_periodic(&emergency_intr_timer,
172 emergency_intr_freq);
174 systimer_adjust_periodic(&emergency_intr_timer, 1);
180 sysctl_emergency_freq(SYSCTL_HANDLER_ARGS)
184 phz = emergency_intr_freq;
185 error = sysctl_handle_int(oidp, &phz, 0, req);
186 if (error || req->newptr == NULL)
190 else if (phz > EMERGENCY_INTR_POLLING_FREQ_MAX)
191 phz = EMERGENCY_INTR_POLLING_FREQ_MAX;
193 emergency_intr_freq = phz;
194 if (emergency_intr_enable) {
195 systimer_adjust_periodic(&emergency_intr_timer,
196 emergency_intr_freq);
198 systimer_adjust_periodic(&emergency_intr_timer, 1);
204 * Register an SWI or INTerrupt handler.
207 register_swi(int intr, inthand2_t *handler, void *arg, const char *name,
208 struct lwkt_serialize *serializer)
210 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
211 panic("register_swi: bad intr %d", intr);
212 return(register_int(intr, handler, arg, name, serializer, 0));
216 register_swi_mp(int intr, inthand2_t *handler, void *arg, const char *name,
217 struct lwkt_serialize *serializer)
219 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
220 panic("register_swi: bad intr %d", intr);
221 return(register_int(intr, handler, arg, name, serializer, INTR_MPSAFE));
225 register_int(int intr, inthand2_t *handler, void *arg, const char *name,
226 struct lwkt_serialize *serializer, int intr_flags)
228 struct intr_info *info;
229 struct intrec **list;
231 int orig_cpuid, cpuid;
233 if (intr < 0 || intr >= MAX_INTS)
234 panic("register_int: bad intr %d", intr);
237 info = &intr_info_ary[intr];
240 * Construct an interrupt handler record
242 rec = kmalloc(sizeof(struct intrec), M_DEVBUF, M_INTWAIT);
243 rec->name = kmalloc(strlen(name) + 1, M_DEVBUF, M_INTWAIT);
244 strcpy(rec->name, name);
247 rec->handler = handler;
250 rec->intr_flags = intr_flags;
252 rec->serializer = serializer;
255 * Create an emergency polling thread and set up a systimer to wake
258 if (emergency_intr_thread.td_kstack == NULL) {
259 lwkt_create(ithread_emergency, NULL, NULL, &emergency_intr_thread,
260 TDF_STOPREQ | TDF_INTTHREAD, -1, "ithread emerg");
261 systimer_init_periodic_nq(&emergency_intr_timer,
262 emergency_intr_timer_callback, &emergency_intr_thread,
263 (emergency_intr_enable ? emergency_intr_freq : 1));
266 int_moveto_destcpu(&orig_cpuid, &cpuid, intr);
269 * Create an interrupt thread if necessary, leave it in an unscheduled
272 if (info->i_state == ISTATE_NOTHREAD) {
273 info->i_state = ISTATE_NORMAL;
274 lwkt_create(ithread_handler, (void *)(intptr_t)intr, NULL,
275 &info->i_thread, TDF_STOPREQ | TDF_INTTHREAD, -1,
277 if (intr >= FIRST_SOFTINT)
278 lwkt_setpri(&info->i_thread, TDPRI_SOFT_NORM);
280 lwkt_setpri(&info->i_thread, TDPRI_INT_MED);
281 info->i_thread.td_preemptable = lwkt_preempt;
284 list = &info->i_reclist;
287 * Keep track of how many fast and slow interrupts we have.
288 * Set i_mplock_required if any handler in the chain requires
289 * the MP lock to operate.
291 if ((intr_flags & INTR_MPSAFE) == 0)
292 info->i_mplock_required = 1;
293 if (intr_flags & INTR_CLOCK)
299 * Enable random number generation keying off of this interrupt.
301 if ((intr_flags & INTR_NOENTROPY) == 0 && info->i_random.sc_enabled == 0) {
302 info->i_random.sc_enabled = 1;
303 info->i_random.sc_intr = intr;
307 * Add the record to the interrupt list.
310 while (*list != NULL)
311 list = &(*list)->next;
316 * Update max_installed_hard_intr to make the emergency intr poll
317 * a bit more efficient.
319 if (intr < FIRST_SOFTINT) {
320 if (max_installed_hard_intr <= intr)
321 max_installed_hard_intr = intr + 1;
323 if (max_installed_soft_intr <= intr)
324 max_installed_soft_intr = intr + 1;
328 * Setup the machine level interrupt vector
330 * XXX temporary workaround for some ACPI brokedness. ACPI installs
331 * its interrupt too early, before the IOAPICs have been configured,
332 * which means the IOAPIC is not enabled by the registration of the
333 * ACPI interrupt. Anything else sharing that IRQ will wind up not
334 * being enabled. Temporarily work around the problem by always
335 * installing and enabling on every new interrupt handler, even
336 * if one has already been setup on that irq.
338 if (intr < FIRST_SOFTINT /* && info->i_slow + info->i_fast == 1*/) {
339 if (machintr_vector_setup(intr, intr_flags))
340 kprintf("machintr_vector_setup: failed on irq %d\n", intr);
343 int_moveto_origcpu(orig_cpuid, cpuid);
349 unregister_swi(void *id)
355 unregister_int(void *id)
357 struct intr_info *info;
358 struct intrec **list;
360 int intr, orig_cpuid, cpuid;
362 intr = ((intrec_t)id)->intr;
364 if (intr < 0 || intr >= MAX_INTS)
365 panic("register_int: bad intr %d", intr);
367 info = &intr_info_ary[intr];
369 int_moveto_destcpu(&orig_cpuid, &cpuid, intr);
372 * Remove the interrupt descriptor, adjust the descriptor count,
373 * and teardown the machine level vector if this was the last interrupt.
376 list = &info->i_reclist;
377 while ((rec = *list) != NULL) {
386 if (rec->intr_flags & INTR_CLOCK)
390 if (intr < FIRST_SOFTINT && info->i_fast + info->i_slow == 0)
391 machintr_vector_teardown(intr);
394 * Clear i_mplock_required if no handlers in the chain require the
397 for (rec0 = info->i_reclist; rec0; rec0 = rec0->next) {
398 if ((rec0->intr_flags & INTR_MPSAFE) == 0)
402 info->i_mplock_required = 0;
407 int_moveto_origcpu(orig_cpuid, cpuid);
413 kfree(rec->name, M_DEVBUF);
414 kfree(rec, M_DEVBUF);
416 kprintf("warning: unregister_int: int %d handler for %s not found\n",
417 intr, ((intrec_t)id)->name);
422 get_registered_name(int intr)
426 if (intr < 0 || intr >= MAX_INTS)
427 panic("register_int: bad intr %d", intr);
429 if ((rec = intr_info_ary[intr].i_reclist) == NULL)
438 count_registered_ints(int intr)
440 struct intr_info *info;
442 if (intr < 0 || intr >= MAX_INTS)
443 panic("register_int: bad intr %d", intr);
444 info = &intr_info_ary[intr];
445 return(info->i_fast + info->i_slow);
449 get_interrupt_counter(int intr)
451 struct intr_info *info;
453 if (intr < 0 || intr >= MAX_INTS)
454 panic("register_int: bad intr %d", intr);
455 info = &intr_info_ary[intr];
456 return(info->i_count);
461 swi_setpriority(int intr, int pri)
463 struct intr_info *info;
465 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
466 panic("register_swi: bad intr %d", intr);
467 info = &intr_info_ary[intr];
468 if (info->i_state != ISTATE_NOTHREAD)
469 lwkt_setpri(&info->i_thread, pri);
473 register_randintr(int intr)
475 struct intr_info *info;
477 if (intr < 0 || intr >= MAX_INTS)
478 panic("register_randintr: bad intr %d", intr);
479 info = &intr_info_ary[intr];
480 info->i_random.sc_intr = intr;
481 info->i_random.sc_enabled = 1;
485 unregister_randintr(int intr)
487 struct intr_info *info;
489 if (intr < 0 || intr >= MAX_INTS)
490 panic("register_swi: bad intr %d", intr);
491 info = &intr_info_ary[intr];
492 info->i_random.sc_enabled = -1;
496 next_registered_randintr(int intr)
498 struct intr_info *info;
500 if (intr < 0 || intr >= MAX_INTS)
501 panic("register_swi: bad intr %d", intr);
502 while (intr < MAX_INTS) {
503 info = &intr_info_ary[intr];
504 if (info->i_random.sc_enabled > 0)
512 * Dispatch an interrupt. If there's nothing to do we have a stray
513 * interrupt and can just return, leaving the interrupt masked.
515 * We need to schedule the interrupt and set its i_running bit. If
516 * we are not on the interrupt thread's cpu we have to send a message
517 * to the correct cpu that will issue the desired action (interlocking
518 * with the interrupt thread's critical section). We do NOT attempt to
519 * reschedule interrupts whos i_running bit is already set because
520 * this would prematurely wakeup a livelock-limited interrupt thread.
522 * i_running is only tested/set on the same cpu as the interrupt thread.
524 * We are NOT in a critical section, which will allow the scheduled
525 * interrupt to preempt us. The MP lock might *NOT* be held here.
530 sched_ithd_remote(void *arg)
532 sched_ithd((int)(intptr_t)arg);
540 struct intr_info *info;
542 info = &intr_info_ary[intr];
545 if (info->i_state != ISTATE_NOTHREAD) {
546 if (info->i_reclist == NULL) {
547 report_stray_interrupt(intr, info);
550 if (info->i_thread.td_gd == mycpu) {
551 if (info->i_running == 0) {
553 if (info->i_state != ISTATE_LIVELOCKED)
554 lwkt_schedule(&info->i_thread); /* MIGHT PREEMPT */
557 lwkt_send_ipiq(info->i_thread.td_gd,
558 sched_ithd_remote, (void *)(intptr_t)intr);
561 if (info->i_running == 0) {
563 if (info->i_state != ISTATE_LIVELOCKED)
564 lwkt_schedule(&info->i_thread); /* MIGHT PREEMPT */
569 report_stray_interrupt(intr, info);
574 report_stray_interrupt(int intr, struct intr_info *info)
576 ++info->i_straycount;
577 if (info->i_straycount < 10) {
578 if (info->i_errorticks == ticks)
580 info->i_errorticks = ticks;
581 kprintf("sched_ithd: stray interrupt %d on cpu %d\n",
583 } else if (info->i_straycount == 10) {
584 kprintf("sched_ithd: %ld stray interrupts %d on cpu %d - "
585 "there will be no further reports\n",
586 info->i_straycount, intr, mycpuid);
591 * This is run from a periodic SYSTIMER (and thus must be MP safe, the BGL
592 * might not be held).
595 ithread_livelock_wakeup(systimer_t st)
597 struct intr_info *info;
599 info = &intr_info_ary[(int)(intptr_t)st->data];
600 if (info->i_state != ISTATE_NOTHREAD)
601 lwkt_schedule(&info->i_thread);
605 * Schedule ithread within fast intr handler
607 * XXX Protect sched_ithd() call with gd_intr_nesting_level?
608 * Interrupts aren't enabled, but still...
611 ithread_fast_sched(int intr, thread_t td)
616 * We are already in critical section, exit it now to
621 crit_enter_quick(td);
627 * This function is called directly from the ICU or APIC vector code assembly
628 * to process an interrupt. The critical section and interrupt deferral
629 * checks have already been done but the function is entered WITHOUT
630 * a critical section held. The BGL may or may not be held.
632 * Must return non-zero if we do not want the vector code to re-enable
633 * the interrupt (which we don't if we have to schedule the interrupt)
635 int ithread_fast_handler(struct intrframe *frame);
638 ithread_fast_handler(struct intrframe *frame)
641 struct intr_info *info;
642 struct intrec **list;
647 TD_INVARIANTS_DECLARE;
652 intr = frame->if_vec;
656 /* We must be in critical section. */
657 KKASSERT(td->td_critcount);
659 info = &intr_info_ary[intr];
662 * If we are not processing any FAST interrupts, just schedule the thing.
664 if (info->i_fast == 0) {
666 ithread_fast_sched(intr, td);
671 * This should not normally occur since interrupts ought to be
672 * masked if the ithread has been scheduled or is running.
678 * Bump the interrupt nesting level to process any FAST interrupts.
679 * Obtain the MP lock as necessary. If the MP lock cannot be obtained,
680 * schedule the interrupt thread to deal with the issue instead.
682 * To reduce overhead, just leave the MP lock held once it has been
685 ++gd->gd_intr_nesting_level;
687 must_schedule = info->i_slow;
692 TD_INVARIANTS_GET(td);
693 list = &info->i_reclist;
695 for (rec = *list; rec; rec = nrec) {
696 /* rec may be invalid after call */
699 if (rec->intr_flags & INTR_CLOCK) {
701 if ((rec->intr_flags & INTR_MPSAFE) == 0 && got_mplock == 0) {
702 if (try_mplock() == 0) {
703 /* Couldn't get the MP lock; just schedule it. */
710 if (rec->serializer) {
711 must_schedule += lwkt_serialize_handler_try(
712 rec->serializer, rec->handler,
713 rec->argument, frame);
715 rec->handler(rec->argument, frame);
717 TD_INVARIANTS_TEST(td, rec->name);
724 --gd->gd_intr_nesting_level;
731 * If we had a problem, or mixed fast and slow interrupt handlers are
732 * registered, schedule the ithread to catch the missed records (it
733 * will just re-run all of them). A return value of 0 indicates that
734 * all handlers have been run and the interrupt can be re-enabled, and
735 * a non-zero return indicates that the interrupt thread controls
738 if (must_schedule > 0)
739 ithread_fast_sched(intr, td);
740 else if (must_schedule == 0)
742 return(must_schedule);
746 * Interrupt threads run this as their main loop.
748 * The handler begins execution outside a critical section and no MP lock.
750 * The i_running state starts at 0. When an interrupt occurs, the hardware
751 * interrupt is disabled and sched_ithd() The HW interrupt remains disabled
752 * until all routines have run. We then call ithread_done() to reenable
753 * the HW interrupt and deschedule us until the next interrupt.
755 * We are responsible for atomically checking i_running and ithread_done()
756 * is responsible for atomically checking for platform-specific delayed
757 * interrupts. i_running for our irq is only set in the context of our cpu,
758 * so a critical section is a sufficient interlock.
760 #define LIVELOCK_TIMEFRAME(freq) ((freq) >> 2) /* 1/4 second */
763 ithread_handler(void *arg)
765 struct intr_info *info;
770 struct intrec **list;
773 struct systimer ill_timer; /* enforced freq. timer */
774 u_int ill_count; /* interrupt livelock counter */
775 TD_INVARIANTS_DECLARE;
778 intr = (int)(intptr_t)arg;
779 info = &intr_info_ary[intr];
780 list = &info->i_reclist;
783 * The loop must be entered with one critical section held. The thread
784 * does not hold the mplock on startup.
787 lseconds = gd->gd_time_seconds;
793 * The chain is only considered MPSAFE if all its interrupt handlers
794 * are MPSAFE. However, if intr_mpsafe has been turned off we
795 * always operate with the BGL.
798 if (info->i_mplock_required != mpheld) {
799 if (info->i_mplock_required) {
800 KKASSERT(mpheld == 0);
804 KKASSERT(mpheld != 0);
811 TD_INVARIANTS_GET(gd->gd_curthread);
814 * If an interrupt is pending, clear i_running and execute the
815 * handlers. Note that certain types of interrupts can re-trigger
816 * and set i_running again.
818 * Each handler is run in a critical section. Note that we run both
819 * FAST and SLOW designated service routines.
821 if (info->i_running) {
826 report_stray_interrupt(intr, info);
828 for (rec = *list; rec; rec = nrec) {
829 /* rec may be invalid after call */
831 if (rec->serializer) {
832 lwkt_serialize_handler_call(rec->serializer, rec->handler,
833 rec->argument, NULL);
835 rec->handler(rec->argument, NULL);
837 TD_INVARIANTS_TEST(gd->gd_curthread, rec->name);
842 * This is our interrupt hook to add rate randomness to the random
845 if (info->i_random.sc_enabled > 0)
846 add_interrupt_randomness(intr);
849 * Unmask the interrupt to allow it to trigger again. This only
850 * applies to certain types of interrupts (typ level interrupts).
851 * This can result in the interrupt retriggering, but the retrigger
852 * will not be processed until we cycle our critical section.
854 * Only unmask interrupts while handlers are installed. It is
855 * possible to hit a situation where no handlers are installed
856 * due to a device driver livelocking and then tearing down its
857 * interrupt on close (the parallel bus being a good example).
860 machintr_intren(intr);
863 * Do a quick exit/enter to catch any higher-priority interrupt
864 * sources, such as the statclock, so thread time accounting
865 * will still work. This may also cause an interrupt to re-trigger.
871 * LIVELOCK STATE MACHINE
873 switch(info->i_state) {
876 * Reset the count each second.
878 if (lseconds != gd->gd_time_seconds) {
879 lseconds = gd->gd_time_seconds;
884 * If we did not exceed the frequency limit, we are done.
885 * If the interrupt has not retriggered we deschedule ourselves.
887 if (ill_count <= livelock_limit) {
888 if (info->i_running == 0) {
889 lwkt_deschedule_self(gd->gd_curthread);
896 * Otherwise we are livelocked. Set up a periodic systimer
897 * to wake the thread up at the limit frequency.
899 kprintf("intr %d at %d/%d hz, livelocked limit engaged!\n",
900 intr, ill_count, livelock_limit);
901 info->i_state = ISTATE_LIVELOCKED;
902 if ((use_limit = livelock_limit) < 100)
904 else if (use_limit > 500000)
906 systimer_init_periodic_nq(&ill_timer, ithread_livelock_wakeup,
907 (void *)(intptr_t)intr, use_limit);
909 case ISTATE_LIVELOCKED:
911 * Wait for our periodic timer to go off. Since the interrupt
912 * has re-armed it can still set i_running, but it will not
913 * reschedule us while we are in a livelocked state.
915 lwkt_deschedule_self(gd->gd_curthread);
919 * Check once a second to see if the livelock condition no
922 if (lseconds != gd->gd_time_seconds) {
923 lseconds = gd->gd_time_seconds;
924 if (ill_count < livelock_lowater) {
925 info->i_state = ISTATE_NORMAL;
926 systimer_del(&ill_timer);
927 kprintf("intr %d at %d/%d hz, livelock removed\n",
928 intr, ill_count, livelock_lowater);
929 } else if (livelock_debug == intr ||
930 (bootverbose && cold)) {
931 kprintf("intr %d at %d/%d hz, in livelock\n",
932 intr, ill_count, livelock_lowater);
943 * Emergency interrupt polling thread. The thread begins execution
944 * outside a critical section with the BGL held.
946 * If emergency interrupt polling is enabled, this thread will
947 * execute all system interrupts not marked INTR_NOPOLL at the
948 * specified polling frequency.
950 * WARNING! This thread runs *ALL* interrupt service routines that
951 * are not marked INTR_NOPOLL, which basically means everything except
952 * the 8254 clock interrupt and the ATA interrupt. It has very high
953 * overhead and should only be used in situations where the machine
954 * cannot otherwise be made to work. Due to the severe performance
955 * degredation, it should not be enabled on production machines.
958 ithread_emergency(void *arg __unused)
960 struct intr_info *info;
963 thread_t td __debugvar = curthread;
964 TD_INVARIANTS_DECLARE;
967 TD_INVARIANTS_GET(td);
970 for (intr = 0; intr < max_installed_hard_intr; ++intr) {
971 info = &intr_info_ary[intr];
972 for (rec = info->i_reclist; rec; rec = nrec) {
973 /* rec may be invalid after call */
975 if ((rec->intr_flags & INTR_NOPOLL) == 0) {
976 if (rec->serializer) {
977 lwkt_serialize_handler_try(rec->serializer,
978 rec->handler, rec->argument, NULL);
980 rec->handler(rec->argument, NULL);
982 TD_INVARIANTS_TEST(td, rec->name);
986 lwkt_deschedule_self(curthread);
992 * Systimer callback - schedule the emergency interrupt poll thread
993 * if emergency polling is enabled.
997 emergency_intr_timer_callback(systimer_t info, struct intrframe *frame __unused)
999 if (emergency_intr_enable)
1000 lwkt_schedule(info->data);
1004 ithread_cpuid(int intr)
1006 const struct intr_info *info;
1008 KKASSERT(intr >= 0 && intr < MAX_INTS);
1009 info = &intr_info_ary[intr];
1011 if (info->i_state == ISTATE_NOTHREAD)
1013 return info->i_thread.td_gd->gd_cpuid;
1017 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt.
1018 * The data for this machine dependent, and the declarations are in machine
1019 * dependent code. The layout of intrnames and intrcnt however is machine
1022 * We do not know the length of intrcnt and intrnames at compile time, so
1023 * calculate things at run time.
1027 sysctl_intrnames(SYSCTL_HANDLER_ARGS)
1029 struct intr_info *info;
1036 for (intr = 0; error == 0 && intr < MAX_INTS; ++intr) {
1037 info = &intr_info_ary[intr];
1041 for (rec = info->i_reclist; rec; rec = rec->next) {
1042 ksnprintf(buf + len, sizeof(buf) - len, "%s%s",
1043 (len ? "/" : ""), rec->name);
1044 len += strlen(buf + len);
1047 ksnprintf(buf, sizeof(buf), "irq%d", intr);
1050 error = SYSCTL_OUT(req, buf, len + 1);
1056 SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD,
1057 NULL, 0, sysctl_intrnames, "", "Interrupt Names");
1060 sysctl_intrcnt(SYSCTL_HANDLER_ARGS)
1062 struct intr_info *info;
1066 for (intr = 0; intr < max_installed_hard_intr; ++intr) {
1067 info = &intr_info_ary[intr];
1069 error = SYSCTL_OUT(req, &info->i_count, sizeof(info->i_count));
1073 for (intr = FIRST_SOFTINT; intr < max_installed_soft_intr; ++intr) {
1074 info = &intr_info_ary[intr];
1076 error = SYSCTL_OUT(req, &info->i_count, sizeof(info->i_count));
1084 SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD,
1085 NULL, 0, sysctl_intrcnt, "", "Interrupt Counts");
1088 int_moveto_destcpu(int *orig_cpuid0, int *cpuid0, int intr)
1090 int orig_cpuid = mycpuid, cpuid;
1094 ksnprintf(envpath, sizeof(envpath), "hw.irq.%d.dest", intr);
1095 kgetenv_int(envpath, &cpuid);
1099 if (cpuid != orig_cpuid)
1100 lwkt_migratecpu(cpuid);
1102 *orig_cpuid0 = orig_cpuid;
1107 int_moveto_origcpu(int orig_cpuid, int cpuid)
1109 if (cpuid != orig_cpuid)
1110 lwkt_migratecpu(orig_cpuid);