1. A processor comprising: an execution unit; and a thread scheduler configured to schedule a plurality of threads for execution by the execution unit in dependence on a respective status for each thread; wherein the execution unit is configured to execute thread scheduling instructions which manage said statuses, the thread scheduling instructions including at least: a thread event enable instruction which sets a status to event-enabled to allow a thread to accept events, a wait instruction which sets the status to suspended pending at least one event upon which continued execution of the thread depends, and a thread event disable instruction which sets the status to event-disabled to stop the thread from accepting events; and wherein said continued execution comprises retrieval of a continuation point vector for the thread.