diff --git a/sys/dev/acpica/Osd/OsdInterrupt.c b/sys/dev/acpica/Osd/OsdInterrupt.c
--- a/sys/dev/acpica/Osd/OsdInterrupt.c
+++ b/sys/dev/acpica/Osd/OsdInterrupt.c
@@ -68,15 +68,7 @@
 
 static UINT32		InterruptOverride;
 
-static void
-acpi_intr_init(struct mtx *lock)
-{
-
-	mtx_init(lock, "ACPI interrupt lock", NULL, MTX_DEF);
-}
-
-SYSINIT(acpi_intr, SI_SUB_DRIVERS, SI_ORDER_FIRST, acpi_intr_init,
-    &acpi_intr_lock);
+MTX_SYSINIT(acpi_intr_lock_init, &acpi_intr_lock, "ACPI interrupt lock", MTX_DEF);
 
 static int
 acpi_intr_handler(void *arg)