From 25c9d95cb5947382643fdb02dee7a6b99bb639a4 Mon Sep 17 00:00:00 2001 From: piso Date: Sun, 6 May 2007 17:02:50 +0000 Subject: Bring in the reminaing bits to make interrupt filtering work: o push much of the i386 and amd64 MD interrupt handling code (intr_machdep.c::intr_execute_handlers()) into MI code (kern_intr.c::ithread_loop()) o move filter handling to kern_intr.c::intr_filter_loop() o factor out the code necessary to mask and ack an interrupt event (intr_machdep.c::intr_eoi_src() and intr_machdep.c::intr_disab_eoi_src()), and make them part of 'struct intr_event', passing them as arguments to kern_intr.c::intr_event_create(). o spawn a private ithread per handler (struct intr_handler::ih_thread) with filter and ithread functions. Approved by: re (implicit?) --- sys/amd64/amd64/intr_machdep.c | 84 ++++++ sys/i386/i386/intr_machdep.c | 86 +++++- sys/kern/kern_intr.c | 576 ++++++++++++++++++++++++++++++++++++++++- sys/sys/interrupt.h | 21 ++ 4 files changed, 760 insertions(+), 7 deletions(-) diff --git a/sys/amd64/amd64/intr_machdep.c b/sys/amd64/amd64/intr_machdep.c index ffd0701..12191db 100644 --- a/sys/amd64/amd64/intr_machdep.c +++ b/sys/amd64/amd64/intr_machdep.c @@ -74,6 +74,12 @@ static struct intsrc *interrupt_sources[NUM_IO_INTS]; static struct mtx intr_table_lock; static STAILQ_HEAD(, pic) pics; +#ifdef INTR_FILTER +static void intr_eoi_src(void *arg); +static void intr_disab_eoi_src(void *arg); +static void intr_event_stray(void *cookie); +#endif + #ifdef SMP static int assign_cpu; @@ -134,8 +140,14 @@ intr_register_source(struct intsrc *isrc) vector = isrc->is_pic->pic_vector(isrc); if (interrupt_sources[vector] != NULL) return (EEXIST); +#ifdef INTR_FILTER + error = intr_event_create(&isrc->is_event, isrc, 0, + (mask_fn)isrc->is_pic->pic_enable_source, + intr_eoi_src, intr_disab_eoi_src, "irq%d:", vector); +#else error = intr_event_create(&isrc->is_event, isrc, 0, (mask_fn)isrc->is_pic->pic_enable_source, "irq%d:", vector); +#endif if (error) return (error); mtx_lock_spin(&intr_table_lock); @@ -212,6 +224,77 @@ intr_config_intr(int vector, enum intr_trigger trig, enum intr_polarity pol) return (isrc->is_pic->pic_config_intr(isrc, trig, pol)); } +#ifdef INTR_FILTER +void +intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) +{ + struct thread *td; + struct intr_event *ie; + int vector; + + td = curthread; + + /* + * We count software interrupts when we process them. The + * code here follows previous practice, but there's an + * argument for counting hardware interrupts when they're + * processed too. + */ + (*isrc->is_count)++; + PCPU_LAZY_INC(cnt.v_intr); + + ie = isrc->is_event; + + /* + * XXX: We assume that IRQ 0 is only used for the ISA timer + * device (clk). + */ + vector = isrc->is_pic->pic_vector(isrc); + if (vector == 0) + clkintr_pending = 1; + + if (intr_event_handle(ie, frame) != 0) + intr_event_stray(isrc); +} + +static void +intr_event_stray(void *cookie) +{ + struct intsrc *isrc; + + isrc = cookie; + /* + * For stray interrupts, mask and EOI the source, bump the + * stray count, and log the condition. + */ + isrc->is_pic->pic_disable_source(isrc, PIC_EOI); + (*isrc->is_straycount)++; + if (*isrc->is_straycount < MAX_STRAY_LOG) + log(LOG_ERR, "stray irq%d\n", isrc->is_pic->pic_vector(isrc)); + else if (*isrc->is_straycount == MAX_STRAY_LOG) + log(LOG_CRIT, + "too many stray irq %d's: not logging anymore\n", + isrc->is_pic->pic_vector(isrc)); +} + +static void +intr_eoi_src(void *arg) +{ + struct intsrc *isrc; + + isrc = arg; + isrc->is_pic->pic_eoi_source(isrc); +} + +static void +intr_disab_eoi_src(void *arg) +{ + struct intsrc *isrc; + + isrc = arg; + isrc->is_pic->pic_disable_source(isrc, PIC_EOI); +} +#else void intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) { @@ -298,6 +381,7 @@ intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) } td->td_intr_nesting_level--; } +#endif void intr_resume(void) diff --git a/sys/i386/i386/intr_machdep.c b/sys/i386/i386/intr_machdep.c index ee34570..9760070 100644 --- a/sys/i386/i386/intr_machdep.c +++ b/sys/i386/i386/intr_machdep.c @@ -65,6 +65,12 @@ static struct intsrc *interrupt_sources[NUM_IO_INTS]; static struct mtx intr_table_lock; static STAILQ_HEAD(, pic) pics; +#ifdef INTR_FILTER +static void intr_eoi_src(void *arg); +static void intr_disab_eoi_src(void *arg); +static void intr_event_stray(void *cookie); +#endif + #ifdef SMP static int assign_cpu; @@ -125,8 +131,14 @@ intr_register_source(struct intsrc *isrc) vector = isrc->is_pic->pic_vector(isrc); if (interrupt_sources[vector] != NULL) return (EEXIST); +#ifdef INTR_FILTER + error = intr_event_create(&isrc->is_event, isrc, 0, + (mask_fn)isrc->is_pic->pic_enable_source, + intr_eoi_src, intr_disab_eoi_src, "irq%d:", vector); +#else error = intr_event_create(&isrc->is_event, isrc, 0, (mask_fn)isrc->is_pic->pic_enable_source, "irq%d:", vector); +#endif if (error) return (error); mtx_lock_spin(&intr_table_lock); @@ -160,7 +172,7 @@ intr_add_handler(const char *name, int vector, driver_filter_t filter, if (isrc == NULL) return (EINVAL); error = intr_event_add_handler(isrc->is_event, name, filter, handler, - arg, intr_priority(flags), flags, cookiep); + arg, intr_priority(flags), flags, cookiep); if (error == 0) { intrcnt_updatename(isrc); mtx_lock_spin(&intr_table_lock); @@ -203,6 +215,77 @@ intr_config_intr(int vector, enum intr_trigger trig, enum intr_polarity pol) return (isrc->is_pic->pic_config_intr(isrc, trig, pol)); } +#ifdef INTR_FILTER +void +intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) +{ + struct thread *td; + struct intr_event *ie; + int vector; + + td = curthread; + + /* + * We count software interrupts when we process them. The + * code here follows previous practice, but there's an + * argument for counting hardware interrupts when they're + * processed too. + */ + (*isrc->is_count)++; + PCPU_LAZY_INC(cnt.v_intr); + + ie = isrc->is_event; + + /* + * XXX: We assume that IRQ 0 is only used for the ISA timer + * device (clk). + */ + vector = isrc->is_pic->pic_vector(isrc); + if (vector == 0) + clkintr_pending = 1; + + if (intr_event_handle(ie, frame) != 0) + intr_event_stray(isrc); +} + +static void +intr_event_stray(void *cookie) +{ + struct intsrc *isrc; + + isrc = cookie; + /* + * For stray interrupts, mask and EOI the source, bump the + * stray count, and log the condition. + */ + isrc->is_pic->pic_disable_source(isrc, PIC_EOI); + (*isrc->is_straycount)++; + if (*isrc->is_straycount < MAX_STRAY_LOG) + log(LOG_ERR, "stray irq%d\n", isrc->is_pic->pic_vector(isrc)); + else if (*isrc->is_straycount == MAX_STRAY_LOG) + log(LOG_CRIT, + "too many stray irq %d's: not logging anymore\n", + isrc->is_pic->pic_vector(isrc)); +} + +static void +intr_eoi_src(void *arg) +{ + struct intsrc *isrc; + + isrc = arg; + isrc->is_pic->pic_eoi_source(isrc); +} + +static void +intr_disab_eoi_src(void *arg) +{ + struct intsrc *isrc; + + isrc = arg; + isrc->is_pic->pic_disable_source(isrc, PIC_EOI); +} +#else void intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) { @@ -289,6 +372,7 @@ intr_execute_handlers(struct intsrc *isrc, struct trapframe *frame) } td->td_intr_nesting_level--; } +#endif void intr_resume(void) diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c index 94e2672..a9adaa1 100644 --- a/sys/kern/kern_intr.c +++ b/sys/kern/kern_intr.c @@ -92,9 +92,19 @@ static TAILQ_HEAD(, intr_event) event_list = TAILQ_HEAD_INITIALIZER(event_list); static void intr_event_update(struct intr_event *ie); +#ifdef INTR_FILTER +static struct intr_thread *ithread_create(const char *name, + struct intr_handler *ih); +#else static struct intr_thread *ithread_create(const char *name); +#endif static void ithread_destroy(struct intr_thread *ithread); -static void ithread_execute_handlers(struct proc *p, struct intr_event *ie); +static void ithread_execute_handlers(struct proc *p, + struct intr_event *ie); +#ifdef INTR_FILTER +static void priv_ithread_execute_handler(struct proc *p, + struct intr_handler *ih); +#endif static void ithread_loop(void *); static void ithread_update(struct intr_thread *ithd); static void start_softintr(void *); @@ -227,6 +237,7 @@ intr_event_update(struct intr_event *ie) CTR2(KTR_INTR, "%s: updated %s", __func__, ie->ie_fullname); } +#ifndef INTR_FILTER int intr_event_create(struct intr_event **event, void *source, int flags, void (*enable)(void *), const char *fmt, ...) @@ -256,6 +267,40 @@ intr_event_create(struct intr_event **event, void *source, int flags, CTR2(KTR_INTR, "%s: created %s", __func__, ie->ie_name); return (0); } +#else +int +intr_event_create(struct intr_event **event, void *source, int flags, + void (*enable)(void *), void (*eoi)(void *), void (*disab)(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_eoi = eoi; + ie->ie_disab = disab; + 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); +} +#endif int intr_event_destroy(struct intr_event *ie) @@ -281,6 +326,7 @@ intr_event_destroy(struct intr_event *ie) return (0); } +#ifndef INTR_FILTER static struct intr_thread * ithread_create(const char *name) { @@ -305,6 +351,32 @@ ithread_create(const char *name) CTR2(KTR_INTR, "%s: created %s", __func__, name); return (ithd); } +#else +static struct intr_thread * +ithread_create(const char *name, struct intr_handler *ih) +{ + 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, ih, &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); +} +#endif static void ithread_destroy(struct intr_thread *ithread) @@ -322,6 +394,7 @@ ithread_destroy(struct intr_thread *ithread) mtx_unlock_spin(&sched_lock); } +#ifndef INTR_FILTER 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, @@ -394,6 +467,89 @@ intr_event_add_handler(struct intr_event *ie, const char *name, *cookiep = ih; return (0); } +#else +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); + + /* For filtered handlers, create a private ithread to run on. */ + if (filter != NULL && handler != NULL) { + mtx_unlock(&ie->ie_lock); + it = ithread_create("intr: newborn", ih); + mtx_lock(&ie->ie_lock); + it->it_event = ie; + ih->ih_thread = it; + ithread_update(it); // XXX - do we really need this?!?!? + } else { /* Create the global per-event 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", ih); + 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); +} +#endif /* * Return the ie_source field from the intr_event an intr_handler is @@ -415,6 +571,7 @@ intr_handler_source(void *cookie) return (ie->ie_source); } +#ifndef INTR_FILTER int intr_event_remove_handler(void *cookie) { @@ -560,6 +717,161 @@ intr_event_schedule_thread(struct intr_event *ie) return (0); } +#else +int +intr_event_remove_handler(void *cookie) +{ + struct intr_handler *handler = (struct intr_handler *)cookie; + struct intr_event *ie; + struct intr_thread *it; +#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 are no ithreads (per event and per handler), 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 && handler->ih_thread == NULL) { + TAILQ_REMOVE(&ie->ie_handlers, handler, ih_next); + mtx_unlock(&ie->ie_lock); + free(handler, M_ITHREAD); + return (0); + } + + /* Private or global ithread? */ + it = (handler->ih_thread) ? handler->ih_thread : ie->ie_thread; + /* + * 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(it->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. + */ + it->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); + /* + * At this point, the handler has been disconnected from the event, + * so we can kill the private ithread if any. + */ + if (handler->ih_thread) { + ithread_destroy(handler->ih_thread); + handler->ih_thread = NULL; + } + 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 (handler != NULL) { + 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_thread *it) +{ + struct intr_entropy entropy; + 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) || it == NULL) + return (EINVAL); + + ctd = curthread; + 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); +} +#endif /* * Add a software interrupt handler to a specified event. If a given event @@ -572,7 +884,7 @@ swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler, struct intr_event *ie; int error; - if (flags & (INTR_FAST | INTR_ENTROPY)) + if (flags & INTR_ENTROPY) return (EINVAL); ie = (eventp != NULL) ? *eventp : NULL; @@ -581,8 +893,13 @@ swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler, if (!(ie->ie_flags & IE_SOFT)) return (EINVAL); } else { - error = intr_event_create(&ie, NULL, IE_SOFT, NULL, - "swi%d:", pri); +#ifdef INTR_FILTER + error = intr_event_create(&ie, NULL, IE_SOFT, + NULL, NULL, NULL, "swi%d:", pri); +#else + error = intr_event_create(&ie, NULL, IE_SOFT, + NULL, "swi%d:", pri); +#endif if (error) return (error); if (eventp != NULL) @@ -615,7 +932,11 @@ swi_sched(void *cookie, int flags) if (!(flags & SWI_DELAY)) { PCPU_LAZY_INC(cnt.v_soft); +#ifdef INTR_FILTER + error = intr_event_schedule_thread(ie, ie->ie_thread); +#else error = intr_event_schedule_thread(ie); +#endif KASSERT(error == 0, ("stray software interrupt")); } } @@ -633,6 +954,39 @@ swi_remove(void *cookie) return (intr_event_remove_handler(cookie)); } +#ifdef INTR_FILTER +static void +priv_ithread_execute_handler(struct proc *p, struct intr_handler *ih) +{ + struct intr_event *ie; + + ie = ih->ih_event; + /* + * 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); + return; + } + + /* 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); +} +#endif + static void ithread_execute_handlers(struct proc *p, struct intr_event *ie) { @@ -674,8 +1028,8 @@ ithread_execute_handlers(struct proc *p, struct intr_event *ie) /* 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); + __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); @@ -716,6 +1070,7 @@ ithread_execute_handlers(struct proc *p, struct intr_event *ie) ie->ie_enable(ie->ie_source); } +#ifndef INTR_FILTER /* * This is the main code for interrupt threads. */ @@ -782,6 +1137,215 @@ ithread_loop(void *arg) mtx_unlock_spin(&sched_lock); } } +#else +/* + * This is the main code for interrupt threads. + */ +static void +ithread_loop(void *arg) +{ + struct intr_thread *ithd; + struct intr_handler *ih; + struct intr_event *ie; + struct thread *td; + struct proc *p; + int priv; + + td = curthread; + p = td->td_proc; + ih = (struct intr_handler *)arg; + priv = (ih->ih_thread != NULL) ? 1 : 0; + ithd = (priv) ? ih->ih_thread : ih->ih_event->ie_thread; + 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); + if (priv) + priv_ithread_execute_handler(p, ih); + else + 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); + } +} + +/* + * Main loop for interrupt filter. + * + * Some architectures (i386, amd64 and arm) require the optional frame + * parameter, and use it as the main argument for fast handler execution + * when ih_argument == NULL. + * + * Return value: + * o FILTER_STRAY: No filter recognized the event, and no + * filter-less handler is registered on this + * line. + * o FILTER_HANDLED: A filter claimed the event and served it. + * o FILTER_SCHEDULE_THREAD: No filter claimed the event, but there's at + * least one filter-less handler on this line. + * o FILTER_HANDLED | + * FILTER_SCHEDULE_THREAD: A filter claimed the event, and asked for + * scheduling the per-handler ithread. + * + * In case an ithread has to be scheduled, in *ithd there will be a + * pointer to a struct intr_thread containing the thread to be + * scheduled. + */ + +int +intr_filter_loop(struct intr_event *ie, struct trapframe *frame, + struct intr_thread **ithd) +{ + struct intr_handler *ih; + void *arg; + int ret, thread_only; + + ret = 0; + thread_only = 0; + TAILQ_FOREACH(ih, &ie->ie_handlers, ih_next) { + /* + * Execute fast interrupt handlers directly. + * To support clock handlers, if a handler registers + * with a NULL argument, then we pass it a pointer to + * a trapframe as its argument. + */ + arg = ((ih->ih_argument == NULL) ? frame : ih->ih_argument); + + CTR5(KTR_INTR, "%s: exec %p/%p(%p) for %s", __func__, + ih->ih_filter, ih->ih_handler, arg, ih->ih_name); + + if (ih->ih_filter != NULL) + ret = ih->ih_filter(arg); + else { + thread_only = 1; + continue; + } + + KASSERT(ret != FILTER_SCHEDULE_THREAD, + ("intr_filter_loop: FILTER_SCHEDULE_THREAD from filter")); + + if (ret & FILTER_STRAY) + continue; + else { + *ithd = ih->ih_thread; + return (ret); + } + } + + /* + * No filters handled the interrupt and we have at least + * one handler without a filter. In this case, we schedule + * all of the filter-less handlers to run in the ithread. + */ + if (thread_only) { + *ithd = ie->ie_thread; + return (FILTER_SCHEDULE_THREAD); + } + return (FILTER_STRAY); +} + +/* + * Main interrupt handling body. + * + * Input: + * o ie: the event connected to this interrupt. + * o frame: some archs (i.e. i386) pass a frame to some. + * handlers as their main argument. + * Return value: + * o 0: everything ok. + * o EINVAL: stray interrupt. + */ +int +intr_event_handle(struct intr_event *ie, struct trapframe *frame) +{ + struct intr_thread *ithd; + struct thread *td; + int thread; + + ithd = NULL; + td = curthread; + + if (ie == NULL || TAILQ_EMPTY(&ie->ie_handlers)) + return (EINVAL); + + td->td_intr_nesting_level++; + thread = 0; + critical_enter(); + thread = intr_filter_loop(ie, frame, &ithd); + + /* + * If the interrupt was fully served, send it an EOI but leave + * it unmasked. Otherwise, mask the source as well as sending + * it an EOI. + */ + if (thread & FILTER_HANDLED) { + if (ie->ie_eoi != NULL) + ie->ie_eoi(ie->ie_source); + } else { + if (ie->ie_disab != NULL) + ie->ie_disab(ie->ie_source); + } + critical_exit(); + + /* Interrupt storm logic */ + if (thread & FILTER_STRAY) { + ie->ie_count++; + if (ie->ie_count < intr_storm_threshold) + printf("Interrupt stray detection not present\n"); + } + + /* Schedule an ithread if needed. */ + if (thread & FILTER_SCHEDULE_THREAD) { + if (intr_event_schedule_thread(ie, ithd) != 0) + panic("%s: impossible stray interrupt", __func__); + } + td->td_intr_nesting_level--; + return (0); +} +#endif #ifdef DDB /* diff --git a/sys/sys/interrupt.h b/sys/sys/interrupt.h index 9ca87d2..b110374 100644 --- a/sys/sys/interrupt.h +++ b/sys/sys/interrupt.h @@ -52,6 +52,7 @@ struct intr_handler { int ih_need; /* Needs service. */ TAILQ_ENTRY(intr_handler) ih_next; /* Next handler for this event. */ u_char ih_pri; /* Priority of this handler. */ + struct intr_thread *ih_thread; /* Ithread for filtered handler. */ }; /* Interrupt handle flags kept in ih_flags */ @@ -72,6 +73,10 @@ struct intr_event { void *ie_source; /* Cookie used by MD code. */ struct intr_thread *ie_thread; /* Thread we are connected to. */ void (*ie_enable)(void *); +#ifdef INTR_FILTER + void (*ie_eoi)(void *); + void (*ie_disab)(void *); +#endif int ie_flags; int ie_count; /* Loop counter. */ int ie_warncnt; /* Rate-check interrupt storm warns. */ @@ -113,17 +118,33 @@ extern char intrnames[]; /* string table containing device names */ #ifdef DDB void db_dump_intr_event(struct intr_event *ie, int handlers); #endif +#ifdef INTR_FILTER +int intr_filter_loop(struct intr_event *ie, struct trapframe *frame, + struct intr_thread **ithd); int intr_event_handle(struct intr_event *ie, struct trapframe *frame); +#endif u_char intr_priority(enum intr_type flags); 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); +#ifndef INTR_FILTER int intr_event_create(struct intr_event **event, void *source, int flags, void (*enable)(void *), const char *fmt, ...) __printflike(5, 6); +#else +int intr_event_create(struct intr_event **event, void *source, + int flags, void (*enable)(void *), void (*eoi)(void *), + void (*disab)(void *), const char *fmt, ...) + __printflike(7, 8); +#endif int intr_event_destroy(struct intr_event *ie); int intr_event_remove_handler(void *cookie); +#ifndef INTR_FILTER int intr_event_schedule_thread(struct intr_event *ie); +#else +int intr_event_schedule_thread(struct intr_event *ie, + struct intr_thread *ithd); +#endif void *intr_handler_source(void *cookie); int swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler, void *arg, int pri, enum intr_type flags, -- cgit v1.1