freebsd-skq/sys/kern/kern_intr.c
njl 95e9f5610b Bump the interrupt storm detection counter to 1000. My slow fileserver
gets a bogus irq storm detected when periodic daily kicks off at 3 am
and disconnects the disk.  Change the print logic to print once per second
when the storm is occurring instead of only once.  Otherwise, it appeared
that something else was causing the errors each night at 3 am since the
print only occurred the first time.

Reviewed by:	jhb
MFC after:	1 week
2007-04-19 01:24:32 +00:00

1007 lines
25 KiB
C

/*-
* Copyright (c) 1997, Stefan Esser <se@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/rtprio.h>
#include <sys/systm.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/ktr.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/random.h>
#include <sys/resourcevar.h>
#include <sys/sched.h>
#include <sys/sysctl.h>
#include <sys/unistd.h>
#include <sys/vmmeter.h>
#include <machine/atomic.h>
#include <machine/cpu.h>
#include <machine/md_var.h>
#include <machine/stdarg.h>
#ifdef DDB
#include <ddb/ddb.h>
#include <ddb/db_sym.h>
#endif
/*
* Describe an interrupt thread. There is one of these per interrupt event.
*/
struct intr_thread {
struct intr_event *it_event;
struct thread *it_thread; /* Kernel thread. */
int it_flags; /* (j) IT_* flags. */
int it_need; /* Needs service. */
};
/* Interrupt thread flags kept in it_flags */
#define IT_DEAD 0x000001 /* Thread is waiting to exit. */
struct intr_entropy {
struct thread *td;
uintptr_t event;
};
struct intr_event *clk_intr_event;
struct intr_event *tty_intr_event;
void *softclock_ih;
void *vm_ih;
static MALLOC_DEFINE(M_ITHREAD, "ithread", "Interrupt Threads");
static int intr_storm_threshold = 1000;
TUNABLE_INT("hw.intr_storm_threshold", &intr_storm_threshold);
SYSCTL_INT(_hw, OID_AUTO, intr_storm_threshold, CTLFLAG_RW,
&intr_storm_threshold, 0,
"Number of consecutive interrupts before storm protection is enabled");
static TAILQ_HEAD(, intr_event) event_list =
TAILQ_HEAD_INITIALIZER(event_list);
static void intr_event_update(struct intr_event *ie);
static struct intr_thread *ithread_create(const char *name);
static void ithread_destroy(struct intr_thread *ithread);
static void ithread_execute_handlers(struct proc *p, struct intr_event *ie);
static void ithread_loop(void *);
static void ithread_update(struct intr_thread *ithd);
static void start_softintr(void *);
/* Map an interrupt type to an ithread priority. */
u_char
intr_priority(enum intr_type flags)
{
u_char pri;
flags &= (INTR_TYPE_TTY | INTR_TYPE_BIO | INTR_TYPE_NET |
INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK | INTR_TYPE_AV);
switch (flags) {
case INTR_TYPE_TTY:
pri = PI_TTYLOW;
break;
case INTR_TYPE_BIO:
/*
* XXX We need to refine this. BSD/OS distinguishes
* between tape and disk priorities.
*/
pri = PI_DISK;
break;
case INTR_TYPE_NET:
pri = PI_NET;
break;
case INTR_TYPE_CAM:
pri = PI_DISK; /* XXX or PI_CAM? */
break;
case INTR_TYPE_AV: /* Audio/video */
pri = PI_AV;
break;
case INTR_TYPE_CLK:
pri = PI_REALTIME;
break;
case INTR_TYPE_MISC:
pri = PI_DULL; /* don't care */
break;
default:
/* We didn't specify an interrupt level. */
panic("intr_priority: no interrupt type in flags");
}
return pri;
}
/*
* Update an ithread based on the associated intr_event.
*/
static void
ithread_update(struct intr_thread *ithd)
{
struct intr_event *ie;
struct thread *td;
u_char pri;
ie = ithd->it_event;
td = ithd->it_thread;
/* Determine the overall priority of this event. */
if (TAILQ_EMPTY(&ie->ie_handlers))
pri = PRI_MAX_ITHD;
else
pri = TAILQ_FIRST(&ie->ie_handlers)->ih_pri;
/* Update name and priority. */
strlcpy(td->td_proc->p_comm, ie->ie_fullname,
sizeof(td->td_proc->p_comm));
mtx_lock_spin(&sched_lock);
sched_prio(td, pri);
mtx_unlock_spin(&sched_lock);
}
/*
* Regenerate the full name of an interrupt event and update its priority.
*/
static void
intr_event_update(struct intr_event *ie)
{
struct intr_handler *ih;
char *last;
int missed, space;
/* Start off with no entropy and just the name of the event. */
mtx_assert(&ie->ie_lock, MA_OWNED);
strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname));
ie->ie_flags &= ~IE_ENTROPY;
missed = 0;
space = 1;
/* Run through all the handlers updating values. */
TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) {
if (strlen(ie->ie_fullname) + strlen(ih->ih_name) + 1 <
sizeof(ie->ie_fullname)) {
strcat(ie->ie_fullname, " ");
strcat(ie->ie_fullname, ih->ih_name);
space = 0;
} else
missed++;
if (ih->ih_flags & IH_ENTROPY)
ie->ie_flags |= IE_ENTROPY;
}
/*
* If the handler names were too long, add +'s to indicate missing
* names. If we run out of room and still have +'s to add, change
* the last character from a + to a *.
*/
last = &ie->ie_fullname[sizeof(ie->ie_fullname) - 2];
while (missed-- > 0) {
if (strlen(ie->ie_fullname) + 1 == sizeof(ie->ie_fullname)) {
if (*last == '+') {
*last = '*';
break;
} else
*last = '+';
} else if (space) {
strcat(ie->ie_fullname, " +");
space = 0;
} else
strcat(ie->ie_fullname, "+");
}
/*
* If this event has an ithread, update it's priority and
* name.
*/
if (ie->ie_thread != NULL)
ithread_update(ie->ie_thread);
CTR2(KTR_INTR, "%s: updated %s", __func__, ie->ie_fullname);
}
int
intr_event_create(struct intr_event **event, void *source, int flags,
void (*enable)(void *), const char *fmt, ...)
{
struct intr_event *ie;
va_list ap;
/* The only valid flag during creation is IE_SOFT. */
if ((flags & ~IE_SOFT) != 0)
return (EINVAL);
ie = malloc(sizeof(struct intr_event), M_ITHREAD, M_WAITOK | M_ZERO);
ie->ie_source = source;
ie->ie_enable = enable;
ie->ie_flags = flags;
TAILQ_INIT(&ie->ie_handlers);
mtx_init(&ie->ie_lock, "intr event", NULL, MTX_DEF);
va_start(ap, fmt);
vsnprintf(ie->ie_name, sizeof(ie->ie_name), fmt, ap);
va_end(ap);
strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname));
mtx_pool_lock(mtxpool_sleep, &event_list);
TAILQ_INSERT_TAIL(&event_list, ie, ie_list);
mtx_pool_unlock(mtxpool_sleep, &event_list);
if (event != NULL)
*event = ie;
CTR2(KTR_INTR, "%s: created %s", __func__, ie->ie_name);
return (0);
}
int
intr_event_destroy(struct intr_event *ie)
{
mtx_lock(&ie->ie_lock);
if (!TAILQ_EMPTY(&ie->ie_handlers)) {
mtx_unlock(&ie->ie_lock);
return (EBUSY);
}
mtx_pool_lock(mtxpool_sleep, &event_list);
TAILQ_REMOVE(&event_list, ie, ie_list);
mtx_pool_unlock(mtxpool_sleep, &event_list);
#ifndef notyet
if (ie->ie_thread != NULL) {
ithread_destroy(ie->ie_thread);
ie->ie_thread = NULL;
}
#endif
mtx_unlock(&ie->ie_lock);
mtx_destroy(&ie->ie_lock);
free(ie, M_ITHREAD);
return (0);
}
static struct intr_thread *
ithread_create(const char *name)
{
struct intr_thread *ithd;
struct thread *td;
struct proc *p;
int error;
ithd = malloc(sizeof(struct intr_thread), M_ITHREAD, M_WAITOK | M_ZERO);
error = kthread_create(ithread_loop, ithd, &p, RFSTOPPED | RFHIGHPID,
0, "%s", name);
if (error)
panic("kthread_create() failed with %d", error);
td = FIRST_THREAD_IN_PROC(p); /* XXXKSE */
mtx_lock_spin(&sched_lock);
sched_class(td, PRI_ITHD);
TD_SET_IWAIT(td);
mtx_unlock_spin(&sched_lock);
td->td_pflags |= TDP_ITHREAD;
ithd->it_thread = td;
CTR2(KTR_INTR, "%s: created %s", __func__, name);
return (ithd);
}
static void
ithread_destroy(struct intr_thread *ithread)
{
struct thread *td;
CTR2(KTR_INTR, "%s: killing %s", __func__, ithread->it_event->ie_name);
td = ithread->it_thread;
mtx_lock_spin(&sched_lock);
ithread->it_flags |= IT_DEAD;
if (TD_AWAITING_INTR(td)) {
TD_CLR_IWAIT(td);
sched_add(td, SRQ_INTR);
}
mtx_unlock_spin(&sched_lock);
}
int
intr_event_add_handler(struct intr_event *ie, const char *name,
driver_filter_t filter, driver_intr_t handler, void *arg, u_char pri,
enum intr_type flags, void **cookiep)
{
struct intr_handler *ih, *temp_ih;
struct intr_thread *it;
if (ie == NULL || name == NULL || (handler == NULL && filter == NULL))
return (EINVAL);
/* Allocate and populate an interrupt handler structure. */
ih = malloc(sizeof(struct intr_handler), M_ITHREAD, M_WAITOK | M_ZERO);
ih->ih_filter = filter;
ih->ih_handler = handler;
ih->ih_argument = arg;
ih->ih_name = name;
ih->ih_event = ie;
ih->ih_pri = pri;
if (flags & INTR_EXCL)
ih->ih_flags = IH_EXCLUSIVE;
if (flags & INTR_MPSAFE)
ih->ih_flags |= IH_MPSAFE;
if (flags & INTR_ENTROPY)
ih->ih_flags |= IH_ENTROPY;
/* We can only have one exclusive handler in a event. */
mtx_lock(&ie->ie_lock);
if (!TAILQ_EMPTY(&ie->ie_handlers)) {
if ((flags & INTR_EXCL) ||
(TAILQ_FIRST(&ie->ie_handlers)->ih_flags & IH_EXCLUSIVE)) {
mtx_unlock(&ie->ie_lock);
free(ih, M_ITHREAD);
return (EINVAL);
}
}
/* Add the new handler to the event in priority order. */
TAILQ_FOREACH(temp_ih, &ie->ie_handlers, ih_next) {
if (temp_ih->ih_pri > ih->ih_pri)
break;
}
if (temp_ih == NULL)
TAILQ_INSERT_TAIL(&ie->ie_handlers, ih, ih_next);
else
TAILQ_INSERT_BEFORE(temp_ih, ih, ih_next);
intr_event_update(ie);
/* Create a thread if we need one. */
while (ie->ie_thread == NULL && handler != NULL) {
if (ie->ie_flags & IE_ADDING_THREAD)
msleep(ie, &ie->ie_lock, 0, "ithread", 0);
else {
ie->ie_flags |= IE_ADDING_THREAD;
mtx_unlock(&ie->ie_lock);
it = ithread_create("intr: newborn");
mtx_lock(&ie->ie_lock);
ie->ie_flags &= ~IE_ADDING_THREAD;
ie->ie_thread = it;
it->it_event = ie;
ithread_update(it);
wakeup(ie);
}
}
CTR3(KTR_INTR, "%s: added %s to %s", __func__, ih->ih_name,
ie->ie_name);
mtx_unlock(&ie->ie_lock);
if (cookiep != NULL)
*cookiep = ih;
return (0);
}
/*
* Return the ie_source field from the intr_event an intr_handler is
* associated with.
*/
void *
intr_handler_source(void *cookie)
{
struct intr_handler *ih;
struct intr_event *ie;
ih = (struct intr_handler *)cookie;
if (ih == NULL)
return (NULL);
ie = ih->ih_event;
KASSERT(ie != NULL,
("interrupt handler \"%s\" has a NULL interrupt event",
ih->ih_name));
return (ie->ie_source);
}
int
intr_event_remove_handler(void *cookie)
{
struct intr_handler *handler = (struct intr_handler *)cookie;
struct intr_event *ie;
#ifdef INVARIANTS
struct intr_handler *ih;
#endif
#ifdef notyet
int dead;
#endif
if (handler == NULL)
return (EINVAL);
ie = handler->ih_event;
KASSERT(ie != NULL,
("interrupt handler \"%s\" has a NULL interrupt event",
handler->ih_name));
mtx_lock(&ie->ie_lock);
CTR3(KTR_INTR, "%s: removing %s from %s", __func__, handler->ih_name,
ie->ie_name);
#ifdef INVARIANTS
TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next)
if (ih == handler)
goto ok;
mtx_unlock(&ie->ie_lock);
panic("interrupt handler \"%s\" not found in interrupt event \"%s\"",
ih->ih_name, ie->ie_name);
ok:
#endif
/*
* If there is no ithread, then just remove the handler and return.
* XXX: Note that an INTR_FAST handler might be running on another
* CPU!
*/
if (ie->ie_thread == NULL) {
TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next);
mtx_unlock(&ie->ie_lock);
free(handler, M_ITHREAD);
return (0);
}
/*
* If the interrupt thread is already running, then just mark this
* handler as being dead and let the ithread do the actual removal.
*
* During a cold boot while cold is set, msleep() does not sleep,
* so we have to remove the handler here rather than letting the
* thread do it.
*/
mtx_lock_spin(&sched_lock);
if (!TD_AWAITING_INTR(ie->ie_thread->it_thread) && !cold) {
handler->ih_flags |= IH_DEAD;
/*
* Ensure that the thread will process the handler list
* again and remove this handler if it has already passed
* it on the list.
*/
ie->ie_thread->it_need = 1;
} else
TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next);
mtx_unlock_spin(&sched_lock);
while (handler->ih_flags & IH_DEAD)
msleep(handler, &ie->ie_lock, 0, "iev_rmh", 0);
intr_event_update(ie);
#ifdef notyet
/*
* XXX: This could be bad in the case of ppbus(8). Also, I think
* this could lead to races of stale data when servicing an
* interrupt.
*/
dead = 1;
TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) {
if (!(ih->ih_flags & IH_FAST)) {
dead = 0;
break;
}
}
if (dead) {
ithread_destroy(ie->ie_thread);
ie->ie_thread = NULL;
}
#endif
mtx_unlock(&ie->ie_lock);
free(handler, M_ITHREAD);
return (0);
}
int
intr_event_schedule_thread(struct intr_event *ie)
{
struct intr_entropy entropy;
struct intr_thread *it;
struct thread *td;
struct thread *ctd;
struct proc *p;
/*
* If no ithread or no handlers, then we have a stray interrupt.
*/
if (ie == NULL || TAILQ_EMPTY(&ie->ie_handlers) ||
ie->ie_thread == NULL)
return (EINVAL);
ctd = curthread;
it = ie->ie_thread;
td = it->it_thread;
p = td->td_proc;
/*
* If any of the handlers for this ithread claim to be good
* sources of entropy, then gather some.
*/
if (harvest.interrupt && ie->ie_flags & IE_ENTROPY) {
CTR3(KTR_INTR, "%s: pid %d (%s) gathering entropy", __func__,
p->p_pid, p->p_comm);
entropy.event = (uintptr_t)ie;
entropy.td = ctd;
random_harvest(&entropy, sizeof(entropy), 2, 0,
RANDOM_INTERRUPT);
}
KASSERT(p != NULL, ("ithread %s has no process", ie->ie_name));
/*
* Set it_need to tell the thread to keep running if it is already
* running. Then, grab sched_lock and see if we actually need to
* put this thread on the runqueue.
*/
it->it_need = 1;
mtx_lock_spin(&sched_lock);
if (TD_AWAITING_INTR(td)) {
CTR3(KTR_INTR, "%s: schedule pid %d (%s)", __func__, p->p_pid,
p->p_comm);
TD_CLR_IWAIT(td);
sched_add(td, SRQ_INTR);
} else {
CTR5(KTR_INTR, "%s: pid %d (%s): it_need %d, state %d",
__func__, p->p_pid, p->p_comm, it->it_need, td->td_state);
}
mtx_unlock_spin(&sched_lock);
return (0);
}
/*
* Add a software interrupt handler to a specified event. If a given event
* is not specified, then a new event is created.
*/
int
swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler,
void *arg, int pri, enum intr_type flags, void **cookiep)
{
struct intr_event *ie;
int error;
if (flags & (INTR_FAST | INTR_ENTROPY))
return (EINVAL);
ie = (eventp != NULL) ? *eventp : NULL;
if (ie != NULL) {
if (!(ie->ie_flags & IE_SOFT))
return (EINVAL);
} else {
error = intr_event_create(&ie, NULL, IE_SOFT, NULL,
"swi%d:", pri);
if (error)
return (error);
if (eventp != NULL)
*eventp = ie;
}
return (intr_event_add_handler(ie, name, NULL, handler, arg,
(pri * RQ_PPQ) + PI_SOFT, flags, cookiep));
/* XXKSE.. think of a better way to get separate queues */
}
/*
* Schedule a software interrupt thread.
*/
void
swi_sched(void *cookie, int flags)
{
struct intr_handler *ih = (struct intr_handler *)cookie;
struct intr_event *ie = ih->ih_event;
int error;
CTR3(KTR_INTR, "swi_sched: %s %s need=%d", ie->ie_name, ih->ih_name,
ih->ih_need);
/*
* Set ih_need for this handler so that if the ithread is already
* running it will execute this handler on the next pass. Otherwise,
* it will execute it the next time it runs.
*/
atomic_store_rel_int(&ih->ih_need, 1);
if (!(flags & SWI_DELAY)) {
PCPU_LAZY_INC(cnt.v_soft);
error = intr_event_schedule_thread(ie);
KASSERT(error == 0, ("stray software interrupt"));
}
}
/*
* Remove a software interrupt handler. Currently this code does not
* remove the associated interrupt event if it becomes empty. Calling code
* may do so manually via intr_event_destroy(), but that's not really
* an optimal interface.
*/
int
swi_remove(void *cookie)
{
return (intr_event_remove_handler(cookie));
}
static void
ithread_execute_handlers(struct proc *p, struct intr_event *ie)
{
struct intr_handler *ih, *ihn;
/* Interrupt handlers should not sleep. */
if (!(ie->ie_flags & IE_SOFT))
THREAD_NO_SLEEPING();
TAILQ_FOREACH_SAFE(ih, &ie->ie_handlers, ih_next, ihn) {
/*
* If this handler is marked for death, remove it from
* the list of handlers and wake up the sleeper.
*/
if (ih->ih_flags & IH_DEAD) {
mtx_lock(&ie->ie_lock);
TAILQ_REMOVE(&ie->ie_handlers, ih, ih_next);
ih->ih_flags &= ~IH_DEAD;
wakeup(ih);
mtx_unlock(&ie->ie_lock);
continue;
}
/* Skip filter only handlers */
if (ih->ih_handler == NULL)
continue;
/*
* For software interrupt threads, we only execute
* handlers that have their need flag set. Hardware
* interrupt threads always invoke all of their handlers.
*/
if (ie->ie_flags & IE_SOFT) {
if (!ih->ih_need)
continue;
else
atomic_store_rel_int(&ih->ih_need, 0);
}
/* Execute this handler. */
CTR6(KTR_INTR, "%s: pid %d exec %p(%p) for %s flg=%x",
__func__, p->p_pid, (void *)ih->ih_handler, ih->ih_argument,
ih->ih_name, ih->ih_flags);
if (!(ih->ih_flags & IH_MPSAFE))
mtx_lock(&Giant);
ih->ih_handler(ih->ih_argument);
if (!(ih->ih_flags & IH_MPSAFE))
mtx_unlock(&Giant);
}
if (!(ie->ie_flags & IE_SOFT))
THREAD_SLEEPING_OK();
/*
* Interrupt storm handling:
*
* If this interrupt source is currently storming, then throttle
* it to only fire the handler once per clock tick.
*
* If this interrupt source is not currently storming, but the
* number of back to back interrupts exceeds the storm threshold,
* then enter storming mode.
*/
if (intr_storm_threshold != 0 && ie->ie_count >= intr_storm_threshold &&
!(ie->ie_flags & IE_SOFT)) {
/* Report the message only once every second. */
if (ppsratecheck(&ie->ie_warntm, &ie->ie_warncnt, 1)) {
printf(
"interrupt storm detected on \"%s\"; throttling interrupt source\n",
ie->ie_name);
}
pause("istorm", 1);
} else
ie->ie_count++;
/*
* Now that all the handlers have had a chance to run, reenable
* the interrupt source.
*/
if (ie->ie_enable != NULL)
ie->ie_enable(ie->ie_source);
}
/*
* This is the main code for interrupt threads.
*/
static void
ithread_loop(void *arg)
{
struct intr_thread *ithd;
struct intr_event *ie;
struct thread *td;
struct proc *p;
td = curthread;
p = td->td_proc;
ithd = (struct intr_thread *)arg;
KASSERT(ithd->it_thread == td,
("%s: ithread and proc linkage out of sync", __func__));
ie = ithd->it_event;
ie->ie_count = 0;
/*
* As long as we have interrupts outstanding, go through the
* list of handlers, giving each one a go at it.
*/
for (;;) {
/*
* If we are an orphaned thread, then just die.
*/
if (ithd->it_flags & IT_DEAD) {
CTR3(KTR_INTR, "%s: pid %d (%s) exiting", __func__,
p->p_pid, p->p_comm);
free(ithd, M_ITHREAD);
kthread_exit(0);
}
/*
* Service interrupts. If another interrupt arrives while
* we are running, it will set it_need to note that we
* should make another pass.
*/
while (ithd->it_need) {
/*
* This might need a full read and write barrier
* to make sure that this write posts before any
* of the memory or device accesses in the
* handlers.
*/
atomic_store_rel_int(&ithd->it_need, 0);
ithread_execute_handlers(p, ie);
}
WITNESS_WARN(WARN_PANIC, NULL, "suspending ithread");
mtx_assert(&Giant, MA_NOTOWNED);
/*
* Processed all our interrupts. Now get the sched
* lock. This may take a while and it_need may get
* set again, so we have to check it again.
*/
mtx_lock_spin(&sched_lock);
if (!ithd->it_need && !(ithd->it_flags & IT_DEAD)) {
TD_SET_IWAIT(td);
ie->ie_count = 0;
mi_switch(SW_VOL, NULL);
}
mtx_unlock_spin(&sched_lock);
}
}
#ifdef DDB
/*
* Dump details about an interrupt handler
*/
static void
db_dump_intrhand(struct intr_handler *ih)
{
int comma;
db_printf("\t%-10s ", ih->ih_name);
switch (ih->ih_pri) {
case PI_REALTIME:
db_printf("CLK ");
break;
case PI_AV:
db_printf("AV ");
break;
case PI_TTYHIGH:
case PI_TTYLOW:
db_printf("TTY ");
break;
case PI_TAPE:
db_printf("TAPE");
break;
case PI_NET:
db_printf("NET ");
break;
case PI_DISK:
case PI_DISKLOW:
db_printf("DISK");
break;
case PI_DULL:
db_printf("DULL");
break;
default:
if (ih->ih_pri >= PI_SOFT)
db_printf("SWI ");
else
db_printf("%4u", ih->ih_pri);
break;
}
db_printf(" ");
db_printsym((uintptr_t)ih->ih_handler, DB_STGY_PROC);
db_printf("(%p)", ih->ih_argument);
if (ih->ih_need ||
(ih->ih_flags & (IH_EXCLUSIVE | IH_ENTROPY | IH_DEAD |
IH_MPSAFE)) != 0) {
db_printf(" {");
comma = 0;
if (ih->ih_flags & IH_EXCLUSIVE) {
if (comma)
db_printf(", ");
db_printf("EXCL");
comma = 1;
}
if (ih->ih_flags & IH_ENTROPY) {
if (comma)
db_printf(", ");
db_printf("ENTROPY");
comma = 1;
}
if (ih->ih_flags & IH_DEAD) {
if (comma)
db_printf(", ");
db_printf("DEAD");
comma = 1;
}
if (ih->ih_flags & IH_MPSAFE) {
if (comma)
db_printf(", ");
db_printf("MPSAFE");
comma = 1;
}
if (ih->ih_need) {
if (comma)
db_printf(", ");
db_printf("NEED");
}
db_printf("}");
}
db_printf("\n");
}
/*
* Dump details about a event.
*/
void
db_dump_intr_event(struct intr_event *ie, int handlers)
{
struct intr_handler *ih;
struct intr_thread *it;
int comma;
db_printf("%s ", ie->ie_fullname);
it = ie->ie_thread;
if (it != NULL)
db_printf("(pid %d)", it->it_thread->td_proc->p_pid);
else
db_printf("(no thread)");
if ((ie->ie_flags & (IE_SOFT | IE_ENTROPY | IE_ADDING_THREAD)) != 0 ||
(it != NULL && it->it_need)) {
db_printf(" {");
comma = 0;
if (ie->ie_flags & IE_SOFT) {
db_printf("SOFT");
comma = 1;
}
if (ie->ie_flags & IE_ENTROPY) {
if (comma)
db_printf(", ");
db_printf("ENTROPY");
comma = 1;
}
if (ie->ie_flags & IE_ADDING_THREAD) {
if (comma)
db_printf(", ");
db_printf("ADDING_THREAD");
comma = 1;
}
if (it != NULL && it->it_need) {
if (comma)
db_printf(", ");
db_printf("NEED");
}
db_printf("}");
}
db_printf("\n");
if (handlers)
TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next)
db_dump_intrhand(ih);
}
/*
* Dump data about interrupt handlers
*/
DB_SHOW_COMMAND(intr, db_show_intr)
{
struct intr_event *ie;
int all, verbose;
verbose = index(modif, 'v') != NULL;
all = index(modif, 'a') != NULL;
TAILQ_FOREACH(ie, &event_list, ie_list) {
if (!all && TAILQ_EMPTY(&ie->ie_handlers))
continue;
db_dump_intr_event(ie, verbose);
if (db_pager_quit)
break;
}
}
#endif /* DDB */
/*
* Start standard software interrupt threads
*/
static void
start_softintr(void *dummy)
{
struct proc *p;
if (swi_add(&clk_intr_event, "clock", softclock, NULL, SWI_CLOCK,
INTR_MPSAFE, &softclock_ih) ||
swi_add(NULL, "vm", swi_vm, NULL, SWI_VM, INTR_MPSAFE, &vm_ih))
panic("died while creating standard software ithreads");
p = clk_intr_event->ie_thread->it_thread->td_proc;
PROC_LOCK(p);
p->p_flag |= P_NOLOAD;
PROC_UNLOCK(p);
}
SYSINIT(start_softintr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_softintr, NULL)
/*
* Sysctls used by systat and others: hw.intrnames and hw.intrcnt.
* The data for this machine dependent, and the declarations are in machine
* dependent code. The layout of intrnames and intrcnt however is machine
* independent.
*
* We do not know the length of intrcnt and intrnames at compile time, so
* calculate things at run time.
*/
static int
sysctl_intrnames(SYSCTL_HANDLER_ARGS)
{
return (sysctl_handle_opaque(oidp, intrnames, eintrnames - intrnames,
req));
}
SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD,
NULL, 0, sysctl_intrnames, "", "Interrupt Names");
static int
sysctl_intrcnt(SYSCTL_HANDLER_ARGS)
{
return (sysctl_handle_opaque(oidp, intrcnt,
(char *)eintrcnt - (char *)intrcnt, req));
}
SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD,
NULL, 0, sysctl_intrcnt, "", "Interrupt Counts");
#ifdef DDB
/*
* DDB command to dump the interrupt statistics.
*/
DB_SHOW_COMMAND(intrcnt, db_show_intrcnt)
{
u_long *i;
char *cp;
cp = intrnames;
for (i = intrcnt; i != eintrcnt && !db_pager_quit; i++) {
if (*cp == '\0')
break;
if (*i != 0)
db_printf("%s\t%lu\n", cp, *i);
cp += strlen(cp) + 1;
}
}
#endif