From ea56e508f0e99b3b28802470373f8402c97f43ad Mon Sep 17 00:00:00 2001
From: Rudi Chiarito <rudi@clarifai.com>
Date: Sat, 2 Jan 2016 23:51:53 -0500
Subject: [PATCH] Fix: deal properly with tc qdisc show returning "noqueue"

---
 pkg/util/bandwidth/linux.go      |  6 ++++++
 pkg/util/bandwidth/linux_test.go | 16 +++++++++++++---
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/pkg/util/bandwidth/linux.go b/pkg/util/bandwidth/linux.go
index dd45e822bac..b5aeaa71487 100644
--- a/pkg/util/bandwidth/linux.go
+++ b/pkg/util/bandwidth/linux.go
@@ -224,6 +224,12 @@ func (t *tcShaper) interfaceExists() (bool, string, error) {
 	if len(value) == 0 {
 		return false, "", nil
 	}
+	// Newer versions of tc and/or the kernel return the following instead of nothing:
+	// qdisc noqueue 0: root refcnt 2
+	fields := strings.Fields(value)
+	if len(fields) > 1 && fields[1] == "noqueue" {
+		return false, "", nil
+	}
 	return true, value, nil
 }
 
diff --git a/pkg/util/bandwidth/linux_test.go b/pkg/util/bandwidth/linux_test.go
index f725570ff86..b6d2b559cd1 100644
--- a/pkg/util/bandwidth/linux_test.go
+++ b/pkg/util/bandwidth/linux_test.go
@@ -492,11 +492,11 @@ func TestReconcileInterfaceExists(t *testing.T) {
 	}
 }
 
-func TestReconcileInterfaceDoesntExist(t *testing.T) {
+func testReconcileInterfaceHasNoData(t *testing.T, output string) {
 	fcmd := exec.FakeCmd{
 		CombinedOutputScript: []exec.FakeCombinedOutputAction{
-			func() ([]byte, error) { return []byte("\n"), nil },
-			func() ([]byte, error) { return []byte("\n"), nil },
+			func() ([]byte, error) { return []byte(output), nil },
+			func() ([]byte, error) { return []byte(output), nil },
 		},
 	}
 
@@ -549,6 +549,16 @@ func TestReconcileInterfaceDoesntExist(t *testing.T) {
 	}
 }
 
+func TestReconcileInterfaceDoesntExist(t *testing.T) {
+	testReconcileInterfaceHasNoData(t, "\n")
+}
+
+var tcQdiscNoqueue = "qdisc noqueue 0: root refcnt 2 \n"
+
+func TestReconcileInterfaceExistsWithNoqueue(t *testing.T) {
+	testReconcileInterfaceHasNoData(t, tcQdiscNoqueue)
+}
+
 var tcQdiscWrong = []string{
 	"qdisc htb 2: root refcnt 2 r2q 10 default 30 direct_packets_stat 0\n",
 	"qdisc foo 1: root refcnt 2 r2q 10 default 30 direct_packets_stat 0\n",