RFR 8010182: Thread safety of Thread get/setName()

[Chris Hegarty]

Thread getName and setName are not thread-safe. The "expected" usage is 
to set a name before starting the thread and only read it thereafter.

It is desirable to support the setting of thread name dynamically, 
mainly for monitoring/management/debugging. The typical scenario is the 
single-writer, multiple-reader case. So, making name volatile is 
sufficient. However, setName also sets the native thread name. This is 
currently restricted to the current thread, since there could be a race 
if the thread is terminating. Making setName synchronized would 
eliminate that race, and allow for the native thread name to be set from 
other threads.

This issue came up on c-i a while back [1].

http://cr.openjdk.java.net/~chegar/8010182/webrev.00/webrev/

-Chris.

[1] 
http://cs.oswego.edu/pipermail/concurrency-interest/2013-March/010935.html