Release SpdySession socket read buffer

net/spdy/spdy_session.cc

Index: net/spdy/spdy_session.cc
diff --git a/net/spdy/spdy_session.cc b/net/spdy/spdy_session.cc
index b6e4a6931062d6afe6ccb7e530eed381172916fa..d7327d3ab1a18c929402b5b9eb03b76f09361b1a 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -740,7 +740,6 @@ SpdySession::SpdySession(const SpdySessionKey& spdy_session_key,
       pool_(NULL),
       http_server_properties_(http_server_properties),
       transport_security_state_(transport_security_state),
-      read_buffer_(new IOBuffer(kReadBufferSize)),
       stream_hi_water_mark_(kFirstStreamId),
       last_accepted_push_stream_id_(0),
       unclaimed_pushed_streams_(this),
@@ -1378,8 +1377,9 @@ size_t SpdySession::DumpMemoryStats(StreamSocket::SocketMemoryStats* stats,
   connection_->DumpMemoryStats(stats);
 
   // |connection_| is estimated in stats->total_size. |read_buffer_| is
-  // estimated in kReadBufferSize. TODO(xunjieli): Make them use EMU().
-  return stats->total_size + kReadBufferSize +
+  // estimated in |read_buffer_size|. TODO(xunjieli): Make them use EMU().
+  size_t read_buffer_size = read_buffer_ ? kReadBufferSize : 0;
+  return stats->total_size + read_buffer_size +
          SpdyEstimateMemoryUsage(spdy_session_key_) +
          SpdyEstimateMemoryUsage(pooled_aliases_) +
          SpdyEstimateMemoryUsage(active_streams_) +
@@ -1869,19 +1869,21 @@ int SpdySession::DoReadLoop(ReadState expected_read_state, int result) {
 }
 
 int SpdySession::DoRead() {
+  DCHECK(!read_buffer_);
   CHECK(in_io_loop_);
 
   CHECK(connection_);
   CHECK(connection_->socket());
   read_state_ = READ_STATE_DO_READ_COMPLETE;
   int rv = ERR_READ_IF_READY_NOT_IMPLEMENTED;
+  read_buffer_ = new IOBuffer(kReadBufferSize);
   if (base::FeatureList::IsEnabled(Socket::kReadIfReadyExperiment)) {
     rv = connection_->socket()->ReadIfReady(
         read_buffer_.get(), kReadBufferSize,
         base::Bind(&SpdySession::PumpReadLoop, weak_factory_.GetWeakPtr(),
                    READ_STATE_DO_READ));
-    // TODO(xunjieli): Follow-up CL to release |read_buffer_|.
-    // https://crbug.com/690915.
+    if (rv == ERR_IO_PENDING)
+      read_buffer_ = nullptr;

[davidben, 2017/03/07 22:53:21]

This could be moved into the line 1895 check, right?

[xunjieli, 2017/03/07 23:09:30]

No, in the case of a normal Read(), we can only release the buffer in
DoReadComplete().

[davidben, 2017/03/07 23:12:37]

Right, but normal Read doesn't hit that code. A normal Read would never go from
DoRead to DoRead I think.

[xunjieli, 2017/03/07 23:39:53]

Done.  Oops.. You are right. I can't believe I missed that case. I moved the
state change here. I think that flows slightly better.

   }
   if (rv == ERR_READ_IF_READY_NOT_IMPLEMENTED) {
     // Fallback to regular Read().
@@ -1896,6 +1898,7 @@ int SpdySession::DoRead() {
 }
 
 int SpdySession::DoReadComplete(int result) {
+  DCHECK(read_buffer_);
   CHECK(in_io_loop_);
 
   // Parse a frame.  For now this code requires that the frame fit into our
@@ -1933,6 +1936,7 @@ int SpdySession::DoReadComplete(int result) {
               SpdyFramer::SPDY_NO_ERROR);
   }
 
+  read_buffer_ = nullptr;
   read_state_ = READ_STATE_DO_READ;
   return OK;
 }