Index: sys/kern/subr_devstat.c
===================================================================
--- sys/kern/subr_devstat.c
+++ sys/kern/subr_devstat.c
@@ -49,17 +49,13 @@
 
 SDT_PROBE_DEFINE2(io, , , start, "struct bio *", "struct devstat *");
 SDT_PROBE_DEFINE2(io, , , done, "struct bio *", "struct devstat *");
-SDT_PROBE_DEFINE2(io, , , wait__start, "struct bio *",
-    "struct devstat *");
-SDT_PROBE_DEFINE2(io, , , wait__done, "struct bio *",
-    "struct devstat *");
-
-#define	DTRACE_DEVSTAT_START()		SDT_PROBE2(io, , , start, NULL, ds)
-#define	DTRACE_DEVSTAT_BIO_START()	SDT_PROBE2(io, , , start, bp, ds)
-#define	DTRACE_DEVSTAT_DONE()		SDT_PROBE2(io, , , done, NULL, ds)
-#define	DTRACE_DEVSTAT_BIO_DONE()	SDT_PROBE2(io, , , done, bp, ds)
-#define	DTRACE_DEVSTAT_WAIT_START()	SDT_PROBE2(io, , , wait__start, NULL, ds)
-#define	DTRACE_DEVSTAT_WAIT_DONE()	SDT_PROBE2(io, , , wait__done, NULL, ds)
+SDT_PROBE_DEFINE2(io, , , wait__start, "struct bio *", "struct devstat *");
+SDT_PROBE_DEFINE2(io, , , wait__done, "struct bio *", "struct devstat *");
+
+#define	DTRACE_IO_START()	SDT_PROBE2(io, , , start, bp, ds)
+#define	DTRACE_IO_DONE()	SDT_PROBE2(io, , , done, bp, ds)
+#define	DTRACE_IO_WAIT_START()	SDT_PROBE2(io, , , wait__start, NULL, ds)
+#define	DTRACE_IO_WAIT_DONE()	SDT_PROBE2(io, , , wait__done, NULL, ds)
 
 static int devstat_num_devs;
 static long devstat_generation = 1;
@@ -245,7 +241,6 @@
 	}
 	ds->start_count++;
 	atomic_add_rel_int(&ds->sequence0, 1);
-	DTRACE_DEVSTAT_START();
 }
 
 void
@@ -260,7 +255,7 @@
 
 	binuptime(&bp->bio_t0);
 	devstat_start_transaction(ds, &bp->bio_t0);
-	DTRACE_DEVSTAT_BIO_START();
+	DTRACE_IO_START();
 }
 
 /*
@@ -332,7 +327,6 @@
 
 	ds->end_count++;
 	atomic_add_rel_int(&ds->sequence0, 1);
-	DTRACE_DEVSTAT_DONE();
 }
 
 void
@@ -363,7 +357,7 @@
 
 	devstat_end_transaction(ds, bp->bio_bcount - bp->bio_resid,
 				DEVSTAT_TAG_SIMPLE, flg, now, &bp->bio_t0);
-	DTRACE_DEVSTAT_BIO_DONE();
+	DTRACE_IO_DONE();
 }
 
 /*