Close idle connections / SPDY sessions when needed.

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 bc8a100379d309e2776202fd42640c9e01552da0..cf1ccd76e76b6ab6549f098fe5eabff31b9b2644 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -331,6 +331,7 @@ net::Error SpdySession::InitializeWithSocket(
 
   state_ = CONNECTED;
   connection_.reset(connection);
+  connection_->AddLayeredPool(this);
   is_secure_ = is_secure;
   certificate_error_code_ = certificate_error_code;
 
@@ -967,6 +968,15 @@ int SpdySession::GetLocalAddress(IPEndPoint* address) const {
   return connection_->socket()->GetLocalAddress(address);
 }
 
+bool SpdySession::CloseOneIdleConnection() {
+  if (num_active_streams() == 0) {
+    // Should delete this.
+    RemoveFromPool();

[mmenke, 2011/10/27 18:52:37]

Is this safe?  It looks to me like there may be no one holding a reference to
|this| when we hit the line "spdy_session_pool_ = NULL;" in RemoveFromPool.

[willchan no longer on Chromium, 2011/11/08 22:26:13]

I'm not sure I understand the worry. When we call RemoveFromPool() here, it may
indeed delete |this|, but since we just return right after, we don't dereference
|this|, so it should be safe. Or does the overall pattern just make you nervous?

[mmenke, 2011/11/08 22:41:04]

We don't dereference |this|, but RemoveFromPool does, right after calling
spdy_session_pool_->Remove() on |this|.  Not clear anyone's holding a reference
to |this| when we reach the "spdy_session_pool_ = NULL;" line.

[willchan no longer on Chromium, 2011/11/15 18:44:06]

Again, great catch. I've fixed this.

+    return true;
+  }
+  return false;
+}
+
 void SpdySession::ActivateStream(SpdyStream* stream) {
   const spdy::SpdyStreamId id = stream->stream_id();
   DCHECK(!IsStreamActive(id));
@@ -1001,6 +1011,10 @@ void SpdySession::DeleteStream(spdy::SpdyStreamId id, int status) {
   if (stream)
     stream->OnClose(status);
   ProcessPendingCreateStreams();
+  if (num_active_streams() == 0 && connection_->IsPoolStalled()) {
+    // Should delete this.
+    RemoveFromPool();
+  }
 }
 
 void SpdySession::RemoveFromPool() {