Sys.dm_os_wait_stats
Cumulative statistics that tells you the length of time each wait type has executed since the last server restart. This DMV can be reset manually
Sys.dm_os_waiting_tasks
This DMV shows the currently waiting session ids.
Sys.dm_tran_locks
This DMV shows all the current locks. It shows you the resources that are being locked. The request status shows whether the lock is granted or it is waiting