diff --git a/src/runtime/pprof/runtime.go b/src/runtime/pprof/runtime.go
index e6aace83e2..b71bbad9a6 100644
--- a/src/runtime/pprof/runtime.go
+++ b/src/runtime/pprof/runtime.go
@@ -16,6 +16,7 @@ func runtime_setProfLabel(labels unsafe.Pointer)
 func runtime_getProfLabel() unsafe.Pointer
 
 // SetGoroutineLabels sets the current goroutine's labels to match ctx.
+// A new goroutine inherits the labels of the goroutine that created it.
 // This is a lower-level API than Do, which should be used instead when possible.
 func SetGoroutineLabels(ctx context.Context) {
 	ctxLabels, _ := ctx.Value(labelContextKey{}).(*labelMap)
@@ -24,6 +25,7 @@ func SetGoroutineLabels(ctx context.Context) {
 
 // Do calls f with a copy of the parent context with the
 // given labels added to the parent's label map.
+// Goroutines spawned while executing f will inherit the augmented label-set.
 // Each key/value pair in labels is inserted into the label map in the
 // order provided, overriding any previous value for the same key.
 // The augmented label map will be set for the duration of the call to f