diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c
--- a/sys/kern/kern_intr.c
+++ b/sys/kern/kern_intr.c
@@ -290,7 +290,8 @@
 	/* The flags valid during creation are IE_SOFT and IE_MULTIPROC. */
 	if ((flags & ~(IE_SOFT | IE_MULTIPROC)) != 0)
 		return (EINVAL);
-	ie = malloc(sizeof(struct intr_event), M_ITHREAD, M_WAITOK | M_ZERO);
+	ie = malloc(sizeof(struct intr_event) + (flags & IE_MULTIPROC ?
+	    sizeof(u_long) * (mp_ncpus - 1) : 0), M_ITHREAD, M_WAITOK | M_ZERO);
 	ie->ie_source = source;
 	ie->ie_pre_ithread = pre_ithread;
 	ie->ie_post_ithread = post_ithread;
@@ -299,6 +300,7 @@
 	ie->ie_flags = flags;
 	ie->ie_irq = irq;
 	ie->ie_cpu = NOCPU;
+	/* ->ie_stray and ->ie_intrcnt[] handled by M_ZERO */
 	CK_SLIST_INIT(&ie->ie_handlers);
 	mtx_init(&ie->ie_lock, "intr event", NULL, MTX_DEF);
 
@@ -1388,9 +1390,29 @@
 	intr_prof_stack_use(td, frame);
 #endif
 
-	/* An interrupt with no event or handlers is a stray interrupt. */
-	if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers))
+	/* An interrupt with no event is a stray interrupt. */
+	if (ie == NULL)
+		return (EINVAL);
+
+	/*
+	 * Note about interrupt counters.  Having per-processor counters avoids
+	 * the need for atomic increment of counters.  Whereas other interrupt
+	 * types will be bound to a single processor and not need atomics.
+	 * Per-processor interrupts are *never* flagged as stray, so stray
+	 * counters don't need atomic increment.
+	 */
+
+	/* Increment the interrupt counter. */
+	if (__predict_false(ie->ie_flags & IE_MULTIPROC))
+		++ie->ie_intrcnt[curcpu];
+	else
+		++ie->ie_intrcnt[0];
+
+	/* An interrupt with no handlers is a stray interrupt. */
+	if (CK_SLIST_EMPTY(&ie->ie_handlers)) {
+		++ie->ie_stray;
 		return (EINVAL);
+	}
 
 	/*
 	 * Execute fast interrupt handlers directly.
@@ -1491,8 +1513,10 @@
 	td->td_intr_nesting_level--;
 #ifdef notyet
 	/* The interrupt is not aknowledged by any filter and has no ithread. */
-	if (!thread && !filter)
+	if (!thread && !filter) {
+		++ie->ie_stray;
 		return (EINVAL);
+	}
 #endif
 	return (0);
 }
diff --git a/sys/sys/interrupt.h b/sys/sys/interrupt.h
--- a/sys/sys/interrupt.h
+++ b/sys/sys/interrupt.h
@@ -127,6 +127,8 @@
 	int		ie_cpu;		/* CPU this event is bound to. */
 	volatile int	ie_phase;	/* Switched to establish a barrier. */
 	volatile int	ie_active[2];	/* Filters in ISR context. */
+	u_long		ie_stray;	/* Stray interrupt counter */
+	u_long		ie_intrcnt[1];	/* Interrupt counter(s) */
 };
 
 /* Interrupt event flags kept in ie_flags. */