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 $
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
33 #include <sys/kernel.h>
34 #include <sys/sysctl.h>
35 #include <sys/thread.h>
37 #include <sys/random.h>
38 #include <sys/serialize.h>
39 #include <sys/interrupt.h>
41 #include <sys/machintr.h>
43 #include <machine/frame.h>
45 #include <sys/thread2.h>
46 #include <sys/mplock2.h>
50 typedef struct intrec {
52 struct intr_info *info;
58 struct lwkt_serialize *serializer;
63 struct thread i_thread;
64 struct random_softc i_random;
66 long i_count; /* interrupts dispatched */
67 int i_mplock_required;
72 unsigned long i_straycount;
73 } intr_info_ary[MAX_INTS];
75 int max_installed_hard_intr;
76 int max_installed_soft_intr;
78 #define EMERGENCY_INTR_POLLING_FREQ_MAX 20000
81 * Assert that callers into interrupt handlers don't return with
82 * dangling tokens, spinlocks, or mp locks.
86 #define TD_INVARIANTS_DECLARE \
90 #define TD_INVARIANTS_GET(td) \
92 spincount = (td)->td_gd->gd_spinlocks_wr; \
93 curstop = (td)->td_toks_stop; \
96 #define TD_INVARIANTS_TEST(td, name) \
98 KASSERT(spincount == (td)->td_gd->gd_spinlocks_wr, \
99 ("spincount mismatch after interrupt handler %s", \
101 KASSERT(curstop == (td)->td_toks_stop, \
102 ("token count mismatch after interrupt handler %s", \
110 #define TD_INVARIANTS_DECLARE
111 #define TD_INVARIANTS_GET(td)
112 #define TD_INVARIANTS_TEST(td, name)
114 #endif /* ndef INVARIANTS */
116 static int sysctl_emergency_freq(SYSCTL_HANDLER_ARGS);
117 static int sysctl_emergency_enable(SYSCTL_HANDLER_ARGS);
118 static void emergency_intr_timer_callback(systimer_t, int, struct intrframe *);
119 static void ithread_handler(void *arg);
120 static void ithread_emergency(void *arg);
121 static void report_stray_interrupt(int intr, struct intr_info *info);
122 static void int_moveto_destcpu(int *, int *, int);
123 static void int_moveto_origcpu(int, int);
125 int intr_info_size = NELEM(intr_info_ary);
127 static struct systimer emergency_intr_timer;
128 static struct thread emergency_intr_thread;
130 #define ISTATE_NOTHREAD 0
131 #define ISTATE_NORMAL 1
132 #define ISTATE_LIVELOCKED 2
134 static int livelock_limit = 40000;
135 static int livelock_lowater = 20000;
136 static int livelock_debug = -1;
137 SYSCTL_INT(_kern, OID_AUTO, livelock_limit,
138 CTLFLAG_RW, &livelock_limit, 0, "Livelock interrupt rate limit");
139 SYSCTL_INT(_kern, OID_AUTO, livelock_lowater,
140 CTLFLAG_RW, &livelock_lowater, 0, "Livelock low-water mark restore");
141 SYSCTL_INT(_kern, OID_AUTO, livelock_debug,
142 CTLFLAG_RW, &livelock_debug, 0, "Livelock debug intr#");
144 static int emergency_intr_enable = 0; /* emergency interrupt polling */
145 TUNABLE_INT("kern.emergency_intr_enable", &emergency_intr_enable);
146 SYSCTL_PROC(_kern, OID_AUTO, emergency_intr_enable, CTLTYPE_INT | CTLFLAG_RW,
147 0, 0, sysctl_emergency_enable, "I", "Emergency Interrupt Poll Enable");
149 static int emergency_intr_freq = 10; /* emergency polling frequency */
150 TUNABLE_INT("kern.emergency_intr_freq", &emergency_intr_freq);
151 SYSCTL_PROC(_kern, OID_AUTO, emergency_intr_freq, CTLTYPE_INT | CTLFLAG_RW,
152 0, 0, sysctl_emergency_freq, "I", "Emergency Interrupt Poll Frequency");
155 * Sysctl support routines
158 sysctl_emergency_enable(SYSCTL_HANDLER_ARGS)
162 enabled = emergency_intr_enable;
163 error = sysctl_handle_int(oidp, &enabled, 0, req);
164 if (error || req->newptr == NULL)
166 emergency_intr_enable = enabled;
167 if (emergency_intr_enable) {
168 systimer_adjust_periodic(&emergency_intr_timer,
169 emergency_intr_freq);
171 systimer_adjust_periodic(&emergency_intr_timer, 1);
177 sysctl_emergency_freq(SYSCTL_HANDLER_ARGS)
181 phz = emergency_intr_freq;
182 error = sysctl_handle_int(oidp, &phz, 0, req);
183 if (error || req->newptr == NULL)
187 else if (phz > EMERGENCY_INTR_POLLING_FREQ_MAX)
188 phz = EMERGENCY_INTR_POLLING_FREQ_MAX;
190 emergency_intr_freq = phz;
191 if (emergency_intr_enable) {
192 systimer_adjust_periodic(&emergency_intr_timer,
193 emergency_intr_freq);
195 systimer_adjust_periodic(&emergency_intr_timer, 1);
201 * Register an SWI or INTerrupt handler.
204 register_swi(int intr, inthand2_t *handler, void *arg, const char *name,
205 struct lwkt_serialize *serializer)
207 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
208 panic("register_swi: bad intr %d", intr);
209 return(register_int(intr, handler, arg, name, serializer, 0));
213 register_swi_mp(int intr, inthand2_t *handler, void *arg, const char *name,
214 struct lwkt_serialize *serializer)
216 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
217 panic("register_swi: bad intr %d", intr);
218 return(register_int(intr, handler, arg, name, serializer, INTR_MPSAFE));
222 register_int(int intr, inthand2_t *handler, void *arg, const char *name,
223 struct lwkt_serialize *serializer, int intr_flags)
225 struct intr_info *info;
226 struct intrec **list;
228 int orig_cpuid, cpuid;
230 if (intr < 0 || intr >= MAX_INTS)
231 panic("register_int: bad intr %d", intr);
234 info = &intr_info_ary[intr];
237 * Construct an interrupt handler record
239 rec = kmalloc(sizeof(struct intrec), M_DEVBUF, M_INTWAIT);
240 rec->name = kmalloc(strlen(name) + 1, M_DEVBUF, M_INTWAIT);
241 strcpy(rec->name, name);
244 rec->handler = handler;
247 rec->intr_flags = intr_flags;
249 rec->serializer = serializer;
252 * Create an emergency polling thread and set up a systimer to wake
255 if (emergency_intr_thread.td_kstack == NULL) {
256 lwkt_create(ithread_emergency, NULL, NULL, &emergency_intr_thread,
257 TDF_STOPREQ | TDF_INTTHREAD, -1, "ithread emerg");
258 systimer_init_periodic_nq(&emergency_intr_timer,
259 emergency_intr_timer_callback, &emergency_intr_thread,
260 (emergency_intr_enable ? emergency_intr_freq : 1));
263 int_moveto_destcpu(&orig_cpuid, &cpuid, intr);
266 * Create an interrupt thread if necessary, leave it in an unscheduled
269 if (info->i_state == ISTATE_NOTHREAD) {
270 info->i_state = ISTATE_NORMAL;
271 lwkt_create(ithread_handler, (void *)(intptr_t)intr, NULL,
272 &info->i_thread, TDF_STOPREQ | TDF_INTTHREAD, -1,
274 if (intr >= FIRST_SOFTINT)
275 lwkt_setpri(&info->i_thread, TDPRI_SOFT_NORM);
277 lwkt_setpri(&info->i_thread, TDPRI_INT_MED);
278 info->i_thread.td_preemptable = lwkt_preempt;
281 list = &info->i_reclist;
284 * Keep track of how many fast and slow interrupts we have.
285 * Set i_mplock_required if any handler in the chain requires
286 * the MP lock to operate.
288 if ((intr_flags & INTR_MPSAFE) == 0)
289 info->i_mplock_required = 1;
290 if (intr_flags & INTR_CLOCK)
296 * Enable random number generation keying off of this interrupt.
298 if ((intr_flags & INTR_NOENTROPY) == 0 && info->i_random.sc_enabled == 0) {
299 info->i_random.sc_enabled = 1;
300 info->i_random.sc_intr = intr;
304 * Add the record to the interrupt list.
307 while (*list != NULL)
308 list = &(*list)->next;
313 * Update max_installed_hard_intr to make the emergency intr poll
314 * a bit more efficient.
316 if (intr < FIRST_SOFTINT) {
317 if (max_installed_hard_intr <= intr)
318 max_installed_hard_intr = intr + 1;
320 if (max_installed_soft_intr <= intr)
321 max_installed_soft_intr = intr + 1;
325 * Setup the machine level interrupt vector
327 if (intr < FIRST_SOFTINT && info->i_slow + info->i_fast == 1)
328 machintr_intr_setup(intr, intr_flags);
330 int_moveto_origcpu(orig_cpuid, cpuid);
336 unregister_swi(void *id)
342 unregister_int(void *id)
344 struct intr_info *info;
345 struct intrec **list;
347 int intr, orig_cpuid, cpuid;
349 intr = ((intrec_t)id)->intr;
351 if (intr < 0 || intr >= MAX_INTS)
352 panic("register_int: bad intr %d", intr);
354 info = &intr_info_ary[intr];
356 int_moveto_destcpu(&orig_cpuid, &cpuid, intr);
359 * Remove the interrupt descriptor, adjust the descriptor count,
360 * and teardown the machine level vector if this was the last interrupt.
363 list = &info->i_reclist;
364 while ((rec = *list) != NULL) {
373 if (rec->intr_flags & INTR_CLOCK)
377 if (intr < FIRST_SOFTINT && info->i_fast + info->i_slow == 0)
378 machintr_intr_teardown(intr);
381 * Clear i_mplock_required if no handlers in the chain require the
384 for (rec0 = info->i_reclist; rec0; rec0 = rec0->next) {
385 if ((rec0->intr_flags & INTR_MPSAFE) == 0)
389 info->i_mplock_required = 0;
394 int_moveto_origcpu(orig_cpuid, cpuid);
400 kfree(rec->name, M_DEVBUF);
401 kfree(rec, M_DEVBUF);
403 kprintf("warning: unregister_int: int %d handler for %s not found\n",
404 intr, ((intrec_t)id)->name);
409 get_registered_name(int intr)
413 if (intr < 0 || intr >= MAX_INTS)
414 panic("register_int: bad intr %d", intr);
416 if ((rec = intr_info_ary[intr].i_reclist) == NULL)
425 count_registered_ints(int intr)
427 struct intr_info *info;
429 if (intr < 0 || intr >= MAX_INTS)
430 panic("register_int: bad intr %d", intr);
431 info = &intr_info_ary[intr];
432 return(info->i_fast + info->i_slow);
436 get_interrupt_counter(int intr)
438 struct intr_info *info;
440 if (intr < 0 || intr >= MAX_INTS)
441 panic("register_int: bad intr %d", intr);
442 info = &intr_info_ary[intr];
443 return(info->i_count);
448 swi_setpriority(int intr, int pri)
450 struct intr_info *info;
452 if (intr < FIRST_SOFTINT || intr >= MAX_INTS)
453 panic("register_swi: bad intr %d", intr);
454 info = &intr_info_ary[intr];
455 if (info->i_state != ISTATE_NOTHREAD)
456 lwkt_setpri(&info->i_thread, pri);
460 register_randintr(int intr)
462 struct intr_info *info;
464 if (intr < 0 || intr >= MAX_INTS)
465 panic("register_randintr: bad intr %d", intr);
466 info = &intr_info_ary[intr];
467 info->i_random.sc_intr = intr;
468 info->i_random.sc_enabled = 1;
472 unregister_randintr(int intr)
474 struct intr_info *info;
476 if (intr < 0 || intr >= MAX_INTS)
477 panic("register_swi: bad intr %d", intr);
478 info = &intr_info_ary[intr];
479 info->i_random.sc_enabled = -1;
483 next_registered_randintr(int intr)
485 struct intr_info *info;
487 if (intr < 0 || intr >= MAX_INTS)
488 panic("register_swi: bad intr %d", intr);
489 while (intr < MAX_INTS) {
490 info = &intr_info_ary[intr];
491 if (info->i_random.sc_enabled > 0)
499 * Dispatch an interrupt. If there's nothing to do we have a stray
500 * interrupt and can just return, leaving the interrupt masked.
502 * We need to schedule the interrupt and set its i_running bit. If
503 * we are not on the interrupt thread's cpu we have to send a message
504 * to the correct cpu that will issue the desired action (interlocking
505 * with the interrupt thread's critical section). We do NOT attempt to
506 * reschedule interrupts whos i_running bit is already set because
507 * this would prematurely wakeup a livelock-limited interrupt thread.
509 * i_running is only tested/set on the same cpu as the interrupt thread.
511 * We are NOT in a critical section, which will allow the scheduled
512 * interrupt to preempt us. The MP lock might *NOT* be held here.
517 sched_ithd_remote(void *arg)
519 sched_ithd((int)(intptr_t)arg);
527 struct intr_info *info;
529 info = &intr_info_ary[intr];
532 if (info->i_state != ISTATE_NOTHREAD) {
533 if (info->i_reclist == NULL) {
534 report_stray_interrupt(intr, info);
537 if (info->i_thread.td_gd == mycpu) {
538 if (info->i_running == 0) {
540 if (info->i_state != ISTATE_LIVELOCKED)
541 lwkt_schedule(&info->i_thread); /* MIGHT PREEMPT */
544 lwkt_send_ipiq(info->i_thread.td_gd,
545 sched_ithd_remote, (void *)(intptr_t)intr);
548 if (info->i_running == 0) {
550 if (info->i_state != ISTATE_LIVELOCKED)
551 lwkt_schedule(&info->i_thread); /* MIGHT PREEMPT */
556 report_stray_interrupt(intr, info);
561 report_stray_interrupt(int intr, struct intr_info *info)
563 ++info->i_straycount;
564 if (info->i_straycount < 10) {
565 if (info->i_errorticks == ticks)
567 info->i_errorticks = ticks;
568 kprintf("sched_ithd: stray interrupt %d on cpu %d\n",
570 } else if (info->i_straycount == 10) {
571 kprintf("sched_ithd: %ld stray interrupts %d on cpu %d - "
572 "there will be no further reports\n",
573 info->i_straycount, intr, mycpuid);
578 * This is run from a periodic SYSTIMER (and thus must be MP safe, the BGL
579 * might not be held).
582 ithread_livelock_wakeup(systimer_t st, int in_ipi __unused,
583 struct intrframe *frame __unused)
585 struct intr_info *info;
587 info = &intr_info_ary[(int)(intptr_t)st->data];
588 if (info->i_state != ISTATE_NOTHREAD)
589 lwkt_schedule(&info->i_thread);
593 * Schedule ithread within fast intr handler
595 * XXX Protect sched_ithd() call with gd_intr_nesting_level?
596 * Interrupts aren't enabled, but still...
599 ithread_fast_sched(int intr, thread_t td)
604 * We are already in critical section, exit it now to
609 crit_enter_quick(td);
615 * This function is called directly from the ICU or APIC vector code assembly
616 * to process an interrupt. The critical section and interrupt deferral
617 * checks have already been done but the function is entered WITHOUT
618 * a critical section held. The BGL may or may not be held.
620 * Must return non-zero if we do not want the vector code to re-enable
621 * the interrupt (which we don't if we have to schedule the interrupt)
623 int ithread_fast_handler(struct intrframe *frame);
626 ithread_fast_handler(struct intrframe *frame)
629 struct intr_info *info;
630 struct intrec **list;
635 TD_INVARIANTS_DECLARE;
640 intr = frame->if_vec;
644 /* We must be in critical section. */
645 KKASSERT(td->td_critcount);
647 info = &intr_info_ary[intr];
650 * If we are not processing any FAST interrupts, just schedule the thing.
652 if (info->i_fast == 0) {
654 ithread_fast_sched(intr, td);
659 * This should not normally occur since interrupts ought to be
660 * masked if the ithread has been scheduled or is running.
666 * Bump the interrupt nesting level to process any FAST interrupts.
667 * Obtain the MP lock as necessary. If the MP lock cannot be obtained,
668 * schedule the interrupt thread to deal with the issue instead.
670 * To reduce overhead, just leave the MP lock held once it has been
673 ++gd->gd_intr_nesting_level;
675 must_schedule = info->i_slow;
680 TD_INVARIANTS_GET(td);
681 list = &info->i_reclist;
683 for (rec = *list; rec; rec = nrec) {
684 /* rec may be invalid after call */
687 if (rec->intr_flags & INTR_CLOCK) {
689 if ((rec->intr_flags & INTR_MPSAFE) == 0 && got_mplock == 0) {
690 if (try_mplock() == 0) {
691 /* Couldn't get the MP lock; just schedule it. */
698 if (rec->serializer) {
699 must_schedule += lwkt_serialize_handler_try(
700 rec->serializer, rec->handler,
701 rec->argument, frame);
703 rec->handler(rec->argument, frame);
705 TD_INVARIANTS_TEST(td, rec->name);
712 --gd->gd_intr_nesting_level;
719 * If we had a problem, or mixed fast and slow interrupt handlers are
720 * registered, schedule the ithread to catch the missed records (it
721 * will just re-run all of them). A return value of 0 indicates that
722 * all handlers have been run and the interrupt can be re-enabled, and
723 * a non-zero return indicates that the interrupt thread controls
726 if (must_schedule > 0)
727 ithread_fast_sched(intr, td);
728 else if (must_schedule == 0)
730 return(must_schedule);
734 * Interrupt threads run this as their main loop.
736 * The handler begins execution outside a critical section and no MP lock.
738 * The i_running state starts at 0. When an interrupt occurs, the hardware
739 * interrupt is disabled and sched_ithd() The HW interrupt remains disabled
740 * until all routines have run. We then call ithread_done() to reenable
741 * the HW interrupt and deschedule us until the next interrupt.
743 * We are responsible for atomically checking i_running and ithread_done()
744 * is responsible for atomically checking for platform-specific delayed
745 * interrupts. i_running for our irq is only set in the context of our cpu,
746 * so a critical section is a sufficient interlock.
748 #define LIVELOCK_TIMEFRAME(freq) ((freq) >> 2) /* 1/4 second */
751 ithread_handler(void *arg)
753 struct intr_info *info;
758 struct intrec **list;
761 struct systimer ill_timer; /* enforced freq. timer */
762 u_int ill_count; /* interrupt livelock counter */
763 TD_INVARIANTS_DECLARE;
766 intr = (int)(intptr_t)arg;
767 info = &intr_info_ary[intr];
768 list = &info->i_reclist;
771 * The loop must be entered with one critical section held. The thread
772 * does not hold the mplock on startup.
775 lseconds = gd->gd_time_seconds;
781 * The chain is only considered MPSAFE if all its interrupt handlers
782 * are MPSAFE. However, if intr_mpsafe has been turned off we
783 * always operate with the BGL.
786 if (info->i_mplock_required != mpheld) {
787 if (info->i_mplock_required) {
788 KKASSERT(mpheld == 0);
792 KKASSERT(mpheld != 0);
799 TD_INVARIANTS_GET(gd->gd_curthread);
802 * If an interrupt is pending, clear i_running and execute the
803 * handlers. Note that certain types of interrupts can re-trigger
804 * and set i_running again.
806 * Each handler is run in a critical section. Note that we run both
807 * FAST and SLOW designated service routines.
809 if (info->i_running) {
814 report_stray_interrupt(intr, info);
816 for (rec = *list; rec; rec = nrec) {
817 /* rec may be invalid after call */
819 if (rec->serializer) {
820 lwkt_serialize_handler_call(rec->serializer, rec->handler,
821 rec->argument, NULL);
823 rec->handler(rec->argument, NULL);
825 TD_INVARIANTS_TEST(gd->gd_curthread, rec->name);
830 * This is our interrupt hook to add rate randomness to the random
833 if (info->i_random.sc_enabled > 0)
834 add_interrupt_randomness(intr);
837 * Unmask the interrupt to allow it to trigger again. This only
838 * applies to certain types of interrupts (typ level interrupts).
839 * This can result in the interrupt retriggering, but the retrigger
840 * will not be processed until we cycle our critical section.
842 * Only unmask interrupts while handlers are installed. It is
843 * possible to hit a situation where no handlers are installed
844 * due to a device driver livelocking and then tearing down its
845 * interrupt on close (the parallel bus being a good example).
847 if (intr < FIRST_SOFTINT && *list)
848 machintr_intr_enable(intr);
851 * Do a quick exit/enter to catch any higher-priority interrupt
852 * sources, such as the statclock, so thread time accounting
853 * will still work. This may also cause an interrupt to re-trigger.
859 * LIVELOCK STATE MACHINE
861 switch(info->i_state) {
864 * Reset the count each second.
866 if (lseconds != gd->gd_time_seconds) {
867 lseconds = gd->gd_time_seconds;
872 * If we did not exceed the frequency limit, we are done.
873 * If the interrupt has not retriggered we deschedule ourselves.
875 if (ill_count <= livelock_limit) {
876 if (info->i_running == 0) {
877 lwkt_deschedule_self(gd->gd_curthread);
884 * Otherwise we are livelocked. Set up a periodic systimer
885 * to wake the thread up at the limit frequency.
887 kprintf("intr %d at %d/%d hz, livelocked limit engaged!\n",
888 intr, ill_count, livelock_limit);
889 info->i_state = ISTATE_LIVELOCKED;
890 if ((use_limit = livelock_limit) < 100)
892 else if (use_limit > 500000)
894 systimer_init_periodic_nq(&ill_timer, ithread_livelock_wakeup,
895 (void *)(intptr_t)intr, use_limit);
897 case ISTATE_LIVELOCKED:
899 * Wait for our periodic timer to go off. Since the interrupt
900 * has re-armed it can still set i_running, but it will not
901 * reschedule us while we are in a livelocked state.
903 lwkt_deschedule_self(gd->gd_curthread);
907 * Check once a second to see if the livelock condition no
910 if (lseconds != gd->gd_time_seconds) {
911 lseconds = gd->gd_time_seconds;
912 if (ill_count < livelock_lowater) {
913 info->i_state = ISTATE_NORMAL;
914 systimer_del(&ill_timer);
915 kprintf("intr %d at %d/%d hz, livelock removed\n",
916 intr, ill_count, livelock_lowater);
917 } else if (livelock_debug == intr ||
918 (bootverbose && cold)) {
919 kprintf("intr %d at %d/%d hz, in livelock\n",
920 intr, ill_count, livelock_lowater);
931 * Emergency interrupt polling thread. The thread begins execution
932 * outside a critical section with the BGL held.
934 * If emergency interrupt polling is enabled, this thread will
935 * execute all system interrupts not marked INTR_NOPOLL at the
936 * specified polling frequency.
938 * WARNING! This thread runs *ALL* interrupt service routines that
939 * are not marked INTR_NOPOLL, which basically means everything except
940 * the 8254 clock interrupt and the ATA interrupt. It has very high
941 * overhead and should only be used in situations where the machine
942 * cannot otherwise be made to work. Due to the severe performance
943 * degredation, it should not be enabled on production machines.
946 ithread_emergency(void *arg __unused)
948 globaldata_t gd = mycpu;
949 struct intr_info *info;
952 TD_INVARIANTS_DECLARE;
956 TD_INVARIANTS_GET(gd->gd_curthread);
959 for (intr = 0; intr < max_installed_hard_intr; ++intr) {
960 info = &intr_info_ary[intr];
961 for (rec = info->i_reclist; rec; rec = nrec) {
962 /* rec may be invalid after call */
964 if ((rec->intr_flags & INTR_NOPOLL) == 0) {
965 if (rec->serializer) {
966 lwkt_serialize_handler_try(rec->serializer,
967 rec->handler, rec->argument, NULL);
969 rec->handler(rec->argument, NULL);
971 TD_INVARIANTS_TEST(gd->gd_curthread, rec->name);
975 lwkt_deschedule_self(gd->gd_curthread);
982 * Systimer callback - schedule the emergency interrupt poll thread
983 * if emergency polling is enabled.
987 emergency_intr_timer_callback(systimer_t info, int in_ipi __unused,
988 struct intrframe *frame __unused)
990 if (emergency_intr_enable)
991 lwkt_schedule(info->data);
995 ithread_cpuid(int intr)
997 const struct intr_info *info;
999 KKASSERT(intr >= 0 && intr < MAX_INTS);
1000 info = &intr_info_ary[intr];
1002 if (info->i_state == ISTATE_NOTHREAD)
1004 return info->i_thread.td_gd->gd_cpuid;
1008 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt.
1009 * The data for this machine dependent, and the declarations are in machine
1010 * dependent code. The layout of intrnames and intrcnt however is machine
1013 * We do not know the length of intrcnt and intrnames at compile time, so
1014 * calculate things at run time.
1018 sysctl_intrnames(SYSCTL_HANDLER_ARGS)
1020 struct intr_info *info;
1027 for (intr = 0; error == 0 && intr < MAX_INTS; ++intr) {
1028 info = &intr_info_ary[intr];
1032 for (rec = info->i_reclist; rec; rec = rec->next) {
1033 ksnprintf(buf + len, sizeof(buf) - len, "%s%s",
1034 (len ? "/" : ""), rec->name);
1035 len += strlen(buf + len);
1038 ksnprintf(buf, sizeof(buf), "irq%d", intr);
1041 error = SYSCTL_OUT(req, buf, len + 1);
1047 SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD,
1048 NULL, 0, sysctl_intrnames, "", "Interrupt Names");
1051 sysctl_intrcnt(SYSCTL_HANDLER_ARGS)
1053 struct intr_info *info;
1057 for (intr = 0; intr < max_installed_hard_intr; ++intr) {
1058 info = &intr_info_ary[intr];
1060 error = SYSCTL_OUT(req, &info->i_count, sizeof(info->i_count));
1064 for (intr = FIRST_SOFTINT; intr < max_installed_soft_intr; ++intr) {
1065 info = &intr_info_ary[intr];
1067 error = SYSCTL_OUT(req, &info->i_count, sizeof(info->i_count));
1075 SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD,
1076 NULL, 0, sysctl_intrcnt, "", "Interrupt Counts");
1079 sysctl_intrcnt_all(SYSCTL_HANDLER_ARGS)
1081 struct intr_info *info;
1085 for (intr = 0; intr < MAX_INTS; ++intr) {
1086 info = &intr_info_ary[intr];
1088 error = SYSCTL_OUT(req, &info->i_count, sizeof(info->i_count));
1096 SYSCTL_PROC(_hw, OID_AUTO, intrcnt_all, CTLTYPE_OPAQUE | CTLFLAG_RD,
1097 NULL, 0, sysctl_intrcnt_all, "", "Interrupt Counts");
1100 int_moveto_destcpu(int *orig_cpuid0, int *cpuid0, int intr)
1102 int orig_cpuid = mycpuid, cpuid;
1106 ksnprintf(envpath, sizeof(envpath), "hw.irq.%d.dest", intr);
1107 kgetenv_int(envpath, &cpuid);
1111 if (cpuid != orig_cpuid)
1112 lwkt_migratecpu(cpuid);
1114 *orig_cpuid0 = orig_cpuid;
1119 int_moveto_origcpu(int orig_cpuid, int cpuid)
1121 if (cpuid != orig_cpuid)
1122 lwkt_migratecpu(orig_cpuid);