Systemtap is a dynamic tracing/instrumenting tool available on Linux. Probes

that are not fired at run time have close to zero overhead.

The following probes are available for NPTL:

Thread creation & Join Probes

=============================

pthread_create - probe for pthread_create

               arg1 = pointer (pthread_t*) to thread

               arg2 = pointer (pthread_attr_t*) to attr

               arg3 = pointer (void *) to start_routine

               arg4 = arguments to start_routine

pthread_start - probe for actual thread creation

              arg1 = struct pthread (members include thread ID, process ID)

              arg2 = address of start_routine

              arg3 = pointer to the list of arguments

pthread_join - probe for pthread_join

             arg1 = thread ID

pthread_join_ret - probe for pthread_join return

                 arg1 = thread ID

                 arg2 = return value

Lock-related Probes

===================

mutex_init    - probe for pthread_mutex_init

              arg1 = address of mutex lock

mutex_acquired - probe for succ. return of pthread_mutex_lock

               arg1 = address of mutex lock

mutex_timedlock_acquired - probe for succ. return of pthread_mutex_timedlock

                         arg1 = address of mutex lock

mutex_entry   - probe for entry to the pthread_mutex_lock function

              arg1 = address of mutex lock

mutex_timedlock_entry - probe for entry to the pthread_mutex_timedlock function

                      arg1 = address of mutex lock, arg2 = address of timespec

mutex_release - probe for pthread_mutex_unlock after the successful release of a

                mutex lock

              arg1 = address of mutex lock

mutex_destroy - probe for pthread_mutex_destroy

              arg1 = address of mutex lock

wrlock_entry - probe for entry to the pthread_rwlock_wrlock function

             arg1 = address of rw lock

rdlock_entry - probe for entry to the pthread_rwlock_rdlock function

             arg1 = address of rw lock

rwlock_destroy - probe for pthread_rwlock_destroy

               arg1 = address of rw lock

wrlock_acquire_write - probe for pthread_rwlock_wrlock (after getting the lock)

                     arg1 = address of rw lock

rdlock_acquire_read - probe for pthread_rwlock_rdlock after successfully getting

                      the lock

                    arg1 = address of rw lock

rwlock_unlock - probe for pthread_rwlock_unlock

              arg1 = address of rw lock

Condition variable Probes

=========================

cond_init - probe for pthread_cond_init

          arg1 = condition

          arg2 = attr

cond_destroy - probe for pthread_cond_destroy

             arg1 = cond

cond_wait - probe for pthread_cond_wait

          arg1 = condition

          arg2 = mutex lock

cond_timedwait - probe for pthread_cond_timedwait

               arg1 = condition

               arg2 = mutex lock

               arg3 = timespec

cond_signal - probe for pthread_cond_signal

            arg1 = condition

cond_broadcast - probe for pthread_cond_broadcast

               arg1 = condition