Close idle connections / SPDY sessions when needed.

net/spdy/spdy_session.cc

 // Copyright (c) 2011 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/spdy/spdy_session.h"
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/message_loop.h"
@@ skipping 313 matching lines @@
 
 net::Error SpdySession::InitializeWithSocket(
     ClientSocketHandle* connection,
     bool is_secure,
     int certificate_error_code) {
   base::StatsCounter spdy_sessions("spdy.sessions");
   spdy_sessions.Increment();
 
   state_ = CONNECTED;
   connection_.reset(connection);
+  connection_->AddLayeredPool(this);
   is_secure_ = is_secure;
   certificate_error_code_ = certificate_error_code;
 
   // Write out any data that we might have to send, such as the settings frame.
   WriteSocketLater();
   net::Error error = ReadSocket();
   if (error == ERR_IO_PENDING)
     return OK;
   return error;
 }
@@ skipping 616 matching lines @@
   return connection_->socket()->GetPeerAddress(address);
 }
 
 int SpdySession::GetLocalAddress(IPEndPoint* address) const {
   if (!connection_->socket())
     return ERR_SOCKET_NOT_CONNECTED;
 
   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));
 
   active_streams_[id] = stream;
 }
 
 void SpdySession::DeleteStream(spdy::SpdyStreamId id, int status) {
   // For push streams, if they are being deleted normally, we leave
   // the stream in the unclaimed_pushed_streams_ list.  However, if
@@ skipping 14 matching lines @@
   ActiveStreamMap::iterator it2 = active_streams_.find(id);
   if (it2 == active_streams_.end())
     return;
 
   // If this is an active stream, call the callback.
   const scoped_refptr<SpdyStream> stream(it2->second);
   active_streams_.erase(it2);
   if (stream)
     stream->OnClose(status);
   ProcessPendingCreateStreams();
+  if (num_active_streams() == 0 && connection_->IsPoolStalled()) {
+    // Should delete this.
+    RemoveFromPool();
+  }
 }
 
 void SpdySession::RemoveFromPool() {
   if (spdy_session_pool_) {
     spdy_session_pool_->Remove(make_scoped_refptr(this));
     spdy_session_pool_ = NULL;
   }
 }
 
 scoped_refptr<SpdyStream> SpdySession::GetActivePushStream(
@@ skipping 706 matching lines @@
   if (it == pending_callback_map_.end())
     return;
 
   OldCompletionCallback* callback = it->second.callback;
   int result = it->second.result;
   pending_callback_map_.erase(it);
   callback->Run(result);
 }
 
 }  // namespace net