1 files changed, 7 insertions, 1 deletions
diff --git a/pkg/flipcall/ctrl_futex.go b/pkg/flipcall/ctrl_futex.go
index 2e8452a02..99410628f 100644
--- a/pkg/flipcall/ctrl_futex.go
+++ b/pkg/flipcall/ctrl_futex.go
@@ -12,6 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//go:build go1.1
+// +build go1.1
+
 package flipcall
 
 import (
@@ -118,7 +121,7 @@ func (ep *Endpoint) ctrlWaitFirst() error {
 	return ep.futexWaitUntilActive()
 }
 
-func (ep *Endpoint) ctrlRoundTrip() error {
+func (ep *Endpoint) ctrlRoundTrip(mayRetainP bool) error {
 	if err := ep.enterFutexWait(); err != nil {
 		return err
 	}
@@ -130,6 +133,9 @@ func (ep *Endpoint) ctrlRoundTrip() error {
 	if err := ep.futexWakePeer(); err != nil {
 		return err
 	}
+	// Since we don't know if the peer Endpoint is in the same process as this
+	// one (in which case it may need our P to run), we allow our P to be
+	// retaken regardless of mayRetainP.
 	return ep.futexWaitUntilActive()
 }