Attempt to close idle connections in higher layer socket pools when a lower layer pool is stalled.

net/socket/client_socket_pool_base.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/socket/client_socket_pool_base.h"
 
 #include <math.h>
 #include "base/compiler_specific.h"
 #include "base/format_macros.h"
 #include "base/logging.h"
@@ skipping 351 matching lines @@
     // NOTE(mmenke):  Wonder if we really need different code for each case
     // here.  Only reason for them now seems to be preconnects.
     if (idle_socket_count() > 0) {
       // There's an idle socket in this pool. Either that's because there's
       // still one in this group, but we got here due to preconnecting bypassing
       // idle sockets, or because there's an idle socket in another group.
       bool closed = CloseOneIdleSocketExceptInGroup(group);
       if (preconnecting && !closed)
         return ERR_PRECONNECT_MAX_SOCKET_LIMIT;
     } else {
-      // We could check if we really have a stalled group here, but it requires
-      // a scan of all groups, so just flip a flag here, and do the check later.
-      request->net_log().AddEvent(
-          NetLog::TYPE_SOCKET_POOL_STALLED_MAX_SOCKETS, NULL);
-      return ERR_IO_PENDING;
+      do {
+        if (!CloseOneIdleConnectionInLayeredPool()) {
+          // We could check if we really have a stalled group here, but it
+          // requires a scan of all groups, so return ERR_IO_PENDING, and do
+          // the check later.
+          request->net_log().AddEvent(
+              NetLog::TYPE_SOCKET_POOL_STALLED_MAX_SOCKETS, NULL);
+          return ERR_IO_PENDING;
+        }
+      } while (ReachedMaxSocketsLimit());
+
+      // It is possible that CloseOneIdleConnectionInLayeredPool() has deleted
+      // our Group (see http://crbug.com/109876), so look it up again
+      // to be safe.
+      group = GetOrCreateGroup(group_name);
     }
   }
 
   // We couldn't find a socket to reuse, and there's space to allocate one,
   // so allocate and connect a new one.
   scoped_ptr<ConnectJob> connect_job(
       connect_job_factory_->NewConnectJob(group_name, *request, this));
 
   connect_job->Initialize(preconnecting);
   int rv = connect_job->Connect();
@@ skipping 826 matching lines @@
   // Delete active jobs.
   STLDeleteElements(&jobs_);
 
   // Cancel pending backup job.
   weak_factory_.InvalidateWeakPtrs();
 }
 
 }  // namespace internal
 
 }  // namespace net