plugin/forward: make Yield not block (#3336)

* plugin/forward: may Yield not block

Yield may block when we're super busy with creating (and looking) for
connection. Set a small timeout on Yield, to skip putting the connection
back in the queue.

Use persistentConn troughout the socket handling code to be more
consistent.

Signed-off-by: Miek Gieben <miek@miek.nl>

Dont do

Signed-off-by: Miek Gieben <miek@miek.nl>

* Set used in Yield

This gives one central place where we update used in the persistConns

Signed-off-by: Miek Gieben <miek@miek.nl>

1 files changed, 2 insertions, 50 deletions

diff --git a/plugin/forward/persistent_test.go b/plugin/forward/persistent_test.go
index f1c906076..1fb239ca7 100644
--- a/plugin/forward/persistent_test.go
+++ b/plugin/forward/persistent_test.go
@@ -82,54 +82,6 @@ func TestCleanupByTimer(t *testing.T) {
 	tr.Yield(c4)
 }
 
-func TestPartialCleanup(t *testing.T) {
-	s := dnstest.NewServer(func(w dns.ResponseWriter, r *dns.Msg) {
-		ret := new(dns.Msg)
-		ret.SetReply(r)
-		w.WriteMsg(ret)
-	})
-	defer s.Close()
-
-	tr := newTransport(s.Addr)
-	tr.SetExpire(100 * time.Millisecond)
-	tr.Start()
-	defer tr.Stop()
-
-	c1, _, _ := tr.Dial("udp")
-	c2, _, _ := tr.Dial("udp")
-	c3, _, _ := tr.Dial("udp")
-	c4, _, _ := tr.Dial("udp")
-	c5, _, _ := tr.Dial("udp")
-
-	tr.Yield(c1)
-	time.Sleep(10 * time.Millisecond)
-	tr.Yield(c2)
-	time.Sleep(10 * time.Millisecond)
-	tr.Yield(c3)
-	time.Sleep(50 * time.Millisecond)
-	tr.Yield(c4)
-	time.Sleep(10 * time.Millisecond)
-	tr.Yield(c5)
-	time.Sleep(40 * time.Millisecond)
-
-	c6, _, _ := tr.Dial("udp")
-	if c6 != c5 {
-		t.Errorf("Expected c6 == c5")
-	}
-	c7, _, _ := tr.Dial("udp")
-	if c7 != c4 {
-		t.Errorf("Expected c7 == c4")
-	}
-	c8, cached, _ := tr.Dial("udp")
-	if cached {
-		t.Error("Expected non-cached connection (c8)")
-	}
-
-	tr.Yield(c6)
-	tr.Yield(c7)
-	tr.Yield(c8)
-}
-
 func TestCleanupAll(t *testing.T) {
 	s := dnstest.NewServer(func(w dns.ResponseWriter, r *dns.Msg) {
 		ret := new(dns.Msg)
@@ -150,12 +102,12 @@ func TestCleanupAll(t *testing.T) {
 		{c3, time.Now()},
 	}
 
-	if tr.len() != 3 {
+	if len(tr.conns["udp"]) != 3 {
 		t.Error("Expected 3 connections")
 	}
 	tr.cleanup(true)
 
-	if tr.len() > 0 {
+	if len(tr.conns["udp"]) > 0 {
 		t.Error("Expected no cached connections")
 	}
 }