Move Thread Name Mapping into ThreadFunc.

base/threading/simple_thread.cc

 // Copyright (c) 2010 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 "base/threading/simple_thread.h"
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/platform_thread.h"
+#include "base/threading/thread_id_name_manager.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace base {
 
 SimpleThread::SimpleThread(const std::string& name_prefix)
     : name_prefix_(name_prefix), name_(name_prefix),
       thread_(), event_(true, false), tid_(0), joined_(false) {
 }
 
 SimpleThread::SimpleThread(const std::string& name_prefix,
@@ skipping 12 matching lines @@
   bool success = PlatformThread::Create(options_.stack_size(), this, &thread_);
   DCHECK(success);
   base::ThreadRestrictions::ScopedAllowWait allow_wait;
   event_.Wait();  // Wait for the thread to complete initialization.
 }
 
 void SimpleThread::Join() {
   DCHECK(HasBeenStarted()) << "Tried to Join a never-started thread.";
   DCHECK(!HasBeenJoined()) << "Tried to Join a thread multiple times.";
   PlatformThread::Join(thread_);
+  ThreadIdNameManager::GetInstance()->RemoveName(&thread_, tid_);

[jar (doing other things), 2013/05/22 19:37:56]

This still scares me a bit if I'm worried about races.  This will run after an
arbitrary amount of time has passed since the thread has gone away.... which
means some other thread may have started, and gotten the previous one's id.

[dsinclair, 2013/05/22 20:22:31]

The ThreadIdNameManager code takes care of this. We remove the thread -> name
pointer which will only be referenced by us. We then only remove the id ->
thread map entry if thread is equal to the provided thread. 

This way, if another thread has come along, it will change id->thread and we'll
leave it, but we'll still clean up our thread->name mapping.

   joined_ = true;
 }
 
 bool SimpleThread::HasBeenStarted() {
   base::ThreadRestrictions::ScopedAllowWait allow_wait;
   return event_.IsSignaled();
 }
 
 void SimpleThread::ThreadMain() {
   tid_ = PlatformThread::CurrentId();
@@ skipping 98 matching lines @@
 
     // A NULL delegate pointer signals us to quit.
     if (!work)
       break;
 
     work->Run();
   }
 }
 
 }  // namespace base