Index: sys/kern/subr_intr.c
===================================================================
--- sys/kern/subr_intr.c
+++ sys/kern/subr_intr.c
@@ -228,10 +228,7 @@
 isrc_increment_count(struct intr_irqsrc *isrc)
 {
 
-	if (isrc->isrc_flags & INTR_ISRCF_PPI)
-		atomic_add_long(&isrc->isrc_count[0], 1);
-	else
-		isrc->isrc_count[0]++;
+	atomic_add_long(isrc->isrc_count, 1);
 }
 
 /*
@@ -241,7 +238,7 @@
 isrc_increment_straycount(struct intr_irqsrc *isrc)
 {
 
-	return (++isrc->isrc_count[1]);
+	return (atomic_fetchadd_long(isrc->isrc_count + 1, 1));
 }
 
 /*