trace_event support for thread names

base/threading/platform_thread.h

 // 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.
 
 // WARNING: You should *NOT* be using this class directly.  PlatformThread is
 // the low-level platform-specific abstraction to the OS's threading interface.
 // You should instead be using a message-loop driven Thread, see thread.h.
 
 #ifndef BASE_THREADING_PLATFORM_THREAD_H_
 #define BASE_THREADING_PLATFORM_THREAD_H_
@@ skipping 56 matching lines @@
 
   // Gets the current thread id, which may be useful for logging purposes.
   static PlatformThreadId CurrentId();
 
   // Yield the current thread so another thread can be scheduled.
   static void YieldCurrentThread();
 
   // Sleeps for the specified duration (units are milliseconds).
   static void Sleep(int duration_ms);
 
-  // Sets the thread name visible to a debugger.  This has no effect otherwise.
+  // Sets the thread name visible to debuggers/tools. This has no effect
+  // otherwise.

[Sigurður Ásgeirsson, 2011/08/04 12:31:39]

As you don't copy the name, I think you've added a requirement on this function
that the string must outlive the PlatformThread?

[nduca, 2011/08/04 18:17:38]

Actually, that's not the case --- the pointer here only goes into TLS, so its
inaccessible once the thread dies. And, we only retrieve the thread name when
called from that thread. 

The restriction is that the thread name has to survive for the duration of the
thread. I will clarify that.

   static void SetName(const char* name);
 
+  // Gets the thread name, if previously set by SetTName.

[Sigurður Ásgeirsson, 2011/08/04 12:31:39]

SetTName->SetName

[nduca, 2011/08/04 18:17:38]

Done.

+  static const char* GetName();
+
   // Creates a new thread.  The |stack_size| parameter can be 0 to indicate
   // that the default stack size should be used.  Upon success,
   // |*thread_handle| will be assigned a handle to the newly created thread,
   // and |delegate|'s ThreadMain method will be executed on the newly created
   // thread.
   // NOTE: When you are done with the thread handle, you must call Join to
   // release system resources associated with the thread.  You must ensure that
   // the Delegate object outlives the thread.
   static bool Create(size_t stack_size, Delegate* delegate,
                      PlatformThreadHandle* thread_handle);
@@ skipping 11 matching lines @@
   static void SetThreadPriority(PlatformThreadHandle handle,
                                 ThreadPriority priority);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PlatformThread);
 };
 
 }  // namespace base
 
 #endif  // BASE_THREADING_PLATFORM_THREAD_H_