The attached patch introduces a pthread wrapper library with initial
instrumentation for pthread_mutex_lock, pthread_mutex_trylock, and
pthread_mutex_unlock.
New tracepoints are introduced for each of those. For the lock function,
two distinct tracepoints are emitted: one before the lock is requested,
another after it has been acquired.

-- 
Stefan Seefeld
CodeSourcery / Mentor Graphics
http://www.mentor.com/embedded-software/