[NOT FOR REVIEW] Instrument net/ with trace events.

net/udp/udp_socket_posix.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/udp/udp_socket_posix.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <net/if.h>
 #include <netdb.h>
@@ skipping 11 matching lines @@
 #include "base/rand_util.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/base/network_activity_monitor.h"
 #include "net/base/sockaddr_storage.h"
 #include "net/log/net_log.h"
 #include "net/socket/socket_descriptor.h"
 #include "net/udp/udp_net_log_parameters.h"
 
+#include "base/trace_event/trace_event.h"
+
 #if defined(OS_ANDROID)
 #include "base/android/build_info.h"
 #include "base/native_library.h"
 #include "base/strings/utf_string_conversions.h"
 #endif
 
 namespace net {
 
 namespace {
 
@@ skipping 363 matching lines @@
   // UDP multicast or broadcast datagrams destined for the bound
   // port.
   rv = setsockopt(socket_, SOL_SOCKET, SO_REUSEPORT, &value, sizeof(value));
 #else
   rv = setsockopt(socket_, SOL_SOCKET, SO_BROADCAST, &value, sizeof(value));
 #endif  // defined(OS_MACOSX)
   return rv == 0 ? OK : MapSystemError(errno);
 }
 
 void UDPSocketPosix::ReadWatcher::OnFileCanReadWithoutBlocking(int) {
+  TRACE_EVENT0(
+      "net", "net::UDPSocketPosix::ReadWatcher::OnFileCanReadWithoutBlocking");
   if (!socket_->read_callback_.is_null())
     socket_->DidCompleteRead();
 }
 
 void UDPSocketPosix::WriteWatcher::OnFileCanWriteWithoutBlocking(int) {
   if (!socket_->write_callback_.is_null())
     socket_->DidCompleteWrite();
 }
 
 void UDPSocketPosix::DoReadCallback(int rv) {
@@ skipping 370 matching lines @@
     return MapSystemError(errno);
 
   return OK;
 }
 
 void UDPSocketPosix::DetachFromThread() {
   base::NonThreadSafe::DetachFromThread();
 }
 
 }  // namespace net