CCSM: Active Filter Support

Active filters see streams of events and n reacting to them, they often want to take CCSM actions.

ccsm_query(acting_task, action_being_taken, associated_computation_component)

Permits client code to do what exactly? Not sure I remember as I write this!

• answers yes/no
• called in immediate DS context,a nd so because of this, it should only read CCSM structures

ccsm_update(acting_task, action_being_taken, associated_computation_component)

• answer success or error (maybe, see below)
• performs cccsm state changes from deferred DS context
  • needs to be robust, because there is a race in that the action we cared about in immediate DS context may no longer exist by deferred context
    • useful to know how often the query and the update take place in different context