Don't set QUIC's write alarm if we are connection flow control blocked.

net/quic/quic_session_test.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_session.h"
 
 #include <set>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/containers/hash_tables.h"
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/quic_crypto_stream.h"
 #include "net/quic/quic_flags.h"
 #include "net/quic/quic_protocol.h"
 #include "net/quic/quic_utils.h"
 #include "net/quic/reliable_quic_stream.h"
 #include "net/quic/test_tools/quic_connection_peer.h"
 #include "net/quic/test_tools/quic_data_stream_peer.h"
+#include "net/quic/test_tools/quic_flow_controller_peer.h"
 #include "net/quic/test_tools/quic_session_peer.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "net/quic/test_tools/reliable_quic_stream_peer.h"
 #include "net/spdy/spdy_framer.h"
 #include "net/test/gtest_util.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using base::hash_map;
 using std::set;
@@ skipping 29 matching lines @@
     const QuicErrorCode error = session()->config()->ProcessPeerHello(
         msg, CLIENT, &error_details);
     EXPECT_EQ(QUIC_NO_ERROR, error);
     session()->OnConfigNegotiated();
     session()->OnCryptoHandshakeEvent(QuicSession::HANDSHAKE_CONFIRMED);
   }
 
   MOCK_METHOD0(OnCanWrite, void());
 };
 
+class TestHeadersStream : public QuicHeadersStream {
+ public:
+  explicit TestHeadersStream(QuicSession* session)
+      : QuicHeadersStream(session) {
+  }
+
+  MOCK_METHOD0(OnCanWrite, void());
+};
+
 class TestStream : public QuicDataStream {
  public:
   TestStream(QuicStreamId id, QuicSession* session)
       : QuicDataStream(id, session) {
   }
 
   using ReliableQuicStream::CloseWriteSide;
 
   virtual uint32 ProcessData(const char* data, uint32 data_len) {
     return data_len;
@@ skipping 71 matching lines @@
 
   void set_writev_consumes_all_data(bool val) {
     writev_consumes_all_data_ = val;
   }
 
   QuicConsumedData SendStreamData() {
     return WritevData(5, IOVector(), 0, true, NULL);
   }
 
  private:
-  TestCryptoStream crypto_stream_;
+  StrictMock<TestCryptoStream> crypto_stream_;
 
   bool writev_consumes_all_data_;
 };
 
 class QuicSessionTest : public ::testing::TestWithParam<QuicVersion> {
  protected:
   QuicSessionTest()
       : connection_(new MockConnection(true, SupportedVersions(GetParam()))),
         session_(connection_, kInitialFlowControlWindowForTest) {
     headers_[":host"] = "www.google.com";
@@ skipping 172 matching lines @@
   session_.MarkWriteBlocked(stream4->id(), kSomeMiddlePriority);
 
   InSequence s;
   StreamBlocker stream2_blocker(&session_, stream2->id());
   EXPECT_CALL(*stream2, OnCanWrite()).WillOnce(
       // Reregister, to test the loop limit.
       InvokeWithoutArgs(&stream2_blocker, &StreamBlocker::MarkWriteBlocked));
   EXPECT_CALL(*stream6, OnCanWrite());
   EXPECT_CALL(*stream4, OnCanWrite());
   session_.OnCanWrite();
-  EXPECT_TRUE(session_.HasPendingWrites());
+  EXPECT_TRUE(session_.WillingAndAbleToWrite());
 }
 
 TEST_P(QuicSessionTest, OnCanWriteBundlesStreams) {
   // Drive congestion control manually.
   MockSendAlgorithm* send_algorithm = new StrictMock<MockSendAlgorithm>;
   QuicConnectionPeer::SetSendAlgorithm(session_.connection(), send_algorithm);
 
   TestStream* stream2 = session_.CreateOutgoingDataStream();
   TestStream* stream4 = session_.CreateOutgoingDataStream();
   TestStream* stream6 = session_.CreateOutgoingDataStream();
@@ skipping 13 matching lines @@
       InvokeWithoutArgs(&session_, &TestSession::SendStreamData)));
   EXPECT_CALL(*stream4, OnCanWrite()).WillOnce(IgnoreResult(
       InvokeWithoutArgs(&session_, &TestSession::SendStreamData)));
   MockPacketWriter* writer =
       static_cast<MockPacketWriter*>(
           QuicConnectionPeer::GetWriter(session_.connection()));
   EXPECT_CALL(*writer, WritePacket(_, _, _, _)).WillOnce(
                   Return(WriteResult(WRITE_STATUS_OK, 0)));
   EXPECT_CALL(*send_algorithm, OnPacketSent(_, _, _, _, _));
   session_.OnCanWrite();
-  EXPECT_FALSE(session_.HasPendingWrites());
+  EXPECT_FALSE(session_.WillingAndAbleToWrite());
 }
 
 TEST_P(QuicSessionTest, OnCanWriteCongestionControlBlocks) {
   InSequence s;
 
   // Drive congestion control manually.
   MockSendAlgorithm* send_algorithm = new StrictMock<MockSendAlgorithm>;
   QuicConnectionPeer::SetSendAlgorithm(session_.connection(), send_algorithm);
 
   TestStream* stream2 = session_.CreateOutgoingDataStream();
   TestStream* stream4 = session_.CreateOutgoingDataStream();
   TestStream* stream6 = session_.CreateOutgoingDataStream();
 
   session_.MarkWriteBlocked(stream2->id(), kSomeMiddlePriority);
   session_.MarkWriteBlocked(stream6->id(), kSomeMiddlePriority);
   session_.MarkWriteBlocked(stream4->id(), kSomeMiddlePriority);
 
   StreamBlocker stream2_blocker(&session_, stream2->id());
   EXPECT_CALL(*send_algorithm, TimeUntilSend(_, _, _)).WillOnce(Return(
       QuicTime::Delta::Zero()));
   EXPECT_CALL(*stream2, OnCanWrite());
   EXPECT_CALL(*send_algorithm, TimeUntilSend(_, _, _)).WillOnce(Return(
       QuicTime::Delta::Zero()));
   EXPECT_CALL(*stream6, OnCanWrite());
   EXPECT_CALL(*send_algorithm, TimeUntilSend(_, _, _)).WillOnce(Return(
       QuicTime::Delta::Infinite()));
   // stream4->OnCanWrite is not called.
 
   session_.OnCanWrite();
-  EXPECT_TRUE(session_.HasPendingWrites());
+  EXPECT_TRUE(session_.WillingAndAbleToWrite());
 
   // Still congestion-control blocked.
   EXPECT_CALL(*send_algorithm, TimeUntilSend(_, _, _)).WillOnce(Return(
       QuicTime::Delta::Infinite()));
   session_.OnCanWrite();
-  EXPECT_TRUE(session_.HasPendingWrites());
+  EXPECT_TRUE(session_.WillingAndAbleToWrite());
 
   // stream4->OnCanWrite is called once the connection stops being
   // congestion-control blocked.
   EXPECT_CALL(*send_algorithm, TimeUntilSend(_, _, _)).WillOnce(Return(
       QuicTime::Delta::Zero()));
   EXPECT_CALL(*stream4, OnCanWrite());
   session_.OnCanWrite();
-  EXPECT_FALSE(session_.HasPendingWrites());
+  EXPECT_FALSE(session_.WillingAndAbleToWrite());
 }
 
 TEST_P(QuicSessionTest, BufferedHandshake) {
   EXPECT_FALSE(session_.HasPendingHandshake());  // Default value.
 
   // Test that blocking other streams does not change our status.
   TestStream* stream2 = session_.CreateOutgoingDataStream();
   StreamBlocker stream2_blocker(&session_, stream2->id());
   stream2_blocker.MarkWriteBlocked();
   EXPECT_FALSE(session_.HasPendingHandshake());
@@ skipping 26 matching lines @@
   EXPECT_CALL(*stream2, OnCanWrite()).WillOnce(
       InvokeWithoutArgs(&stream2_blocker, &StreamBlocker::MarkWriteBlocked));
 
   EXPECT_CALL(*stream3, OnCanWrite()).WillOnce(
       InvokeWithoutArgs(&stream3_blocker, &StreamBlocker::MarkWriteBlocked));
 
   EXPECT_CALL(*stream4, OnCanWrite()).WillOnce(
       InvokeWithoutArgs(&stream4_blocker, &StreamBlocker::MarkWriteBlocked));
 
   session_.OnCanWrite();
-  EXPECT_TRUE(session_.HasPendingWrites());
+  EXPECT_TRUE(session_.WillingAndAbleToWrite());
   EXPECT_FALSE(session_.HasPendingHandshake());  // Crypto stream wrote.
 }
 
 TEST_P(QuicSessionTest, OnCanWriteWithClosedStream) {
   TestStream* stream2 = session_.CreateOutgoingDataStream();
   TestStream* stream4 = session_.CreateOutgoingDataStream();
   TestStream* stream6 = session_.CreateOutgoingDataStream();
 
   session_.MarkWriteBlocked(stream2->id(), kSomeMiddlePriority);
   session_.MarkWriteBlocked(stream6->id(), kSomeMiddlePriority);
   session_.MarkWriteBlocked(stream4->id(), kSomeMiddlePriority);
   CloseStream(stream6->id());
 
   InSequence s;
   EXPECT_CALL(*stream2, OnCanWrite());
   EXPECT_CALL(*stream4, OnCanWrite());
   session_.OnCanWrite();
-  EXPECT_FALSE(session_.HasPendingWrites());
+  EXPECT_FALSE(session_.WillingAndAbleToWrite());
+}
+
+TEST_P(QuicSessionTest, OnCanWriteLimitsNumWritesIfFlowControlBlocked) {
+  ValueRestore<bool> old_flag(&FLAGS_enable_quic_connection_flow_control, true);
+  if (version() < QUIC_VERSION_19) {
+    return;
+  }
+
+  // Ensure connection level flow control blockage.
+  QuicFlowControllerPeer::SetSendWindowOffset(session_.flow_controller(), 0);
+  EXPECT_TRUE(session_.flow_controller()->IsBlocked());
+
+  // Mark the crypto and headers streams as write blocked, we expect them to be
+  // allowed to write later.
+  session_.MarkWriteBlocked(kCryptoStreamId, kHighestPriority);
+  session_.MarkWriteBlocked(kHeadersStreamId, kHighestPriority);
+
+  // Create a data stream, and although it is write blocked we never expect it
+  // to be allowed to write as we are connection level flow control blocked.
+  TestStream* stream = session_.CreateOutgoingDataStream();
+  session_.MarkWriteBlocked(stream->id(), kSomeMiddlePriority);
+  EXPECT_CALL(*stream, OnCanWrite()).Times(0);
+
+  // The crypto and headers streams should be called even though we are
+  // connection flow control blocked.
+  TestCryptoStream* crypto_stream = session_.GetCryptoStream();
+  EXPECT_CALL(*crypto_stream, OnCanWrite()).Times(1);
+  TestHeadersStream* headers_stream = new TestHeadersStream(&session_);
+  QuicSessionPeer::SetHeadersStream(&session_, headers_stream);
+  EXPECT_CALL(*headers_stream, OnCanWrite()).Times(1);
+
+  session_.OnCanWrite();
+  EXPECT_FALSE(session_.WillingAndAbleToWrite());
 }
 
 TEST_P(QuicSessionTest, SendGoAway) {
   EXPECT_CALL(*connection_,
               SendGoAway(QUIC_PEER_GOING_AWAY, 0u, "Going Away."));
   session_.SendGoAway(QUIC_PEER_GOING_AWAY, "Going Away.");
   EXPECT_TRUE(session_.goaway_sent());
 
   EXPECT_CALL(*connection_,
               SendRstStream(3u, QUIC_STREAM_PEER_GOING_AWAY, 0)).Times(0);
@@ skipping 118 matching lines @@
   const uint32 kSmallerFlowControlWindow = kDefaultFlowControlSendWindow - 1;
   TestSession session(connection, kSmallerFlowControlWindow);
 
   EXPECT_EQ(kDefaultFlowControlSendWindow,
             session.max_flow_control_receive_window_bytes());
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net