diff options
Diffstat (limited to 'freebsd/sys/kern/kern_intr.c')
| -rw-r--r-- | freebsd/sys/kern/kern_intr.c | 104 |
1 files changed, 95 insertions, 9 deletions
diff --git a/freebsd/sys/kern/kern_intr.c b/freebsd/sys/kern/kern_intr.c index 20117eac..9c647eb6 100644 --- a/freebsd/sys/kern/kern_intr.c +++ b/freebsd/sys/kern/kern_intr.c @@ -756,6 +756,28 @@ intr_event_barrier(struct intr_event *ie) atomic_thread_fence_acq(); } +static void +intr_handler_barrier(struct intr_handler *handler) +{ + struct intr_event *ie; + + ie = handler->ih_event; + mtx_assert(&ie->ie_lock, MA_OWNED); + KASSERT((handler->ih_flags & IH_DEAD) == 0, + ("update for a removed handler")); + + if (ie->ie_thread == NULL) { + intr_event_barrier(ie); + return; + } + if ((handler->ih_flags & IH_CHANGED) == 0) { + handler->ih_flags |= IH_CHANGED; + intr_event_schedule_thread(ie); + } + while ((handler->ih_flags & IH_CHANGED) != 0) + msleep(handler, &ie->ie_lock, 0, "ih_barr", 0); +} + /* * Sleep until an ithread finishes executing an interrupt handler. * @@ -880,6 +902,49 @@ intr_event_remove_handler(void *cookie) } #endif /* __rtems__ */ +int +intr_event_suspend_handler(void *cookie) +{ + struct intr_handler *handler = (struct intr_handler *)cookie; + struct intr_event *ie; + + 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); + handler->ih_flags |= IH_SUSP; + intr_handler_barrier(handler); + mtx_unlock(&ie->ie_lock); + return (0); +} + +int +intr_event_resume_handler(void *cookie) +{ + struct intr_handler *handler = (struct intr_handler *)cookie; + struct intr_event *ie; + + if (handler == NULL) + return (EINVAL); + ie = handler->ih_event; + KASSERT(ie != NULL, + ("interrupt handler \"%s\" has a NULL interrupt event", + handler->ih_name)); + + /* + * intr_handler_barrier() acts not only as a barrier, + * it also allows to check for any pending interrupts. + */ + mtx_lock(&ie->ie_lock); + handler->ih_flags &= ~IH_SUSP; + intr_handler_barrier(handler); + mtx_unlock(&ie->ie_lock); + return (0); +} + static int intr_event_schedule_thread(struct intr_event *ie) { @@ -1068,10 +1133,21 @@ intr_event_execute_handlers(struct proc *p, struct intr_event *ie) */ ihp = ih; + if ((ih->ih_flags & IH_CHANGED) != 0) { + mtx_lock(&ie->ie_lock); + ih->ih_flags &= ~IH_CHANGED; + wakeup(ih); + mtx_unlock(&ie->ie_lock); + } + /* Skip filter only handlers */ if (ih->ih_handler == NULL) continue; + /* Skip suspended handlers */ + if ((ih->ih_flags & IH_SUSP) != 0) + continue; + /* * For software interrupt threads, we only execute * handlers that have their need flag set. Hardware @@ -1255,8 +1331,9 @@ intr_event_handle(struct intr_event *ie, struct trapframe *frame) struct intr_handler *ih; struct trapframe *oldframe; struct thread *td; - int ret, thread; int phase; + int ret; + bool filter, thread; td = curthread; @@ -1275,7 +1352,8 @@ intr_event_handle(struct intr_event *ie, struct trapframe *frame) * a trapframe as its argument. */ td->td_intr_nesting_level++; - thread = 0; + filter = false; + thread = false; ret = 0; critical_enter(); oldframe = td->td_intr_frame; @@ -1291,8 +1369,10 @@ intr_event_handle(struct intr_event *ie, struct trapframe *frame) atomic_thread_fence_seq_cst(); CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) { + if ((ih->ih_flags & IH_SUSP) != 0) + continue; if (ih->ih_filter == NULL) { - thread = 1; + thread = true; continue; } CTR4(KTR_INTR, "%s: exec %p(%p) for %s", __func__, @@ -1307,24 +1387,25 @@ intr_event_handle(struct intr_event *ie, struct trapframe *frame) (ret & ~(FILTER_SCHEDULE_THREAD | FILTER_HANDLED)) == 0), ("%s: incorrect return value %#x from %s", __func__, ret, ih->ih_name)); + filter = filter || ret == FILTER_HANDLED; - /* + /* * Wrapper handler special handling: * - * in some particular cases (like pccard and pccbb), + * in some particular cases (like pccard and pccbb), * the _real_ device handler is wrapped in a couple of * functions - a filter wrapper and an ithread wrapper. - * In this case (and just in this case), the filter wrapper + * In this case (and just in this case), the filter wrapper * could ask the system to schedule the ithread and mask * the interrupt source if the wrapped handler is composed * of just an ithread handler. * - * TODO: write a generic wrapper to avoid people rolling - * their own + * TODO: write a generic wrapper to avoid people rolling + * their own. */ if (!thread) { if (ret == FILTER_SCHEDULE_THREAD) - thread = 1; + thread = true; } } atomic_add_rel_int(&ie->ie_active[phase], -1); @@ -1348,6 +1429,11 @@ intr_event_handle(struct intr_event *ie, struct trapframe *frame) } critical_exit(); td->td_intr_nesting_level--; +#ifdef notyet + /* The interrupt is not aknowledged by any filter and has no ithread. */ + if (!thread && !filter) + return (EINVAL); +#endif return (0); } |