Type ASSEMBLE
Source Lines : 170
Fixes Applied : 0
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [Unmodified]
Module
DMTWAT
Function
THE DMTWAT MODULE IS A TASK SERVICE ROUTINE WHICH
IS CALLED DIRECTLY FROM TASK PROGRAMS BY MEANS OF
BRANCH AND LINK. DMTWAT PROVIDES EVENT
SYNCHRONIZATION BY MEANS OF SUSPENDING A TASK'S
EXECUTION UNTIL SOME SPECIFIED EVENT IS SIGNALLED
COMPLETE BY ANOTHER PROCESS IN THE SYSTEM.
Attributes
REUSABLE, NON-INTERRUPTABLE
Operation
DMTWAT BEGINS BY SUSPENDING THE CALLING TASK'S
EXECUTION THROUGH THE FREEZE SVC. IF A SINGLE
SYNCH LOCK IS SPECIFIED IN THE CALL, IT IS
INSPECTED TO SEE IF IT HAS ALREADY BEEN POSTED.
IF THE SPECIFIED SYNCH LOCK IS POSTED, CONTROL IS
IMMEDIATELY PASSED TO DMTDSP, THE MSUP DISPATCHER.
IF THE SYNCH LOCK IS NOT POSTED, THE "WAITING" BIT
IS SET IN THE CALLING TASK'S TASK ELEMENT, THE
ADDRESS OF THE TASK ELEMENT IS SET IN THE SYNCH
LOCK, AND CONTROL IS PASSED TO THE DISPATCHER.
IF A LIST OF SYNCH LOCKS IS SPECIFIED IN THE CALL,
EACH SYNCH LOCK IN THE LIST WHICH IS NOT FLAGGED
TO BE SKIPPED IS INSPECTED TO SEE IF IT HAS
ALREADY BEEN POSTED. IF AT LEAST ONE HAS BEEN
POSTED, CONTROL IS IMMEDIATELY PASSED TO THE MSUP
DISPATCHER. IF NO SYNCH LOCK IN THE LIST IS
POSTED, THE "WAITING" AND "LOCKLIST" BITS IN THE
CALLING TASK'S TASK ELEMENT ARE SET TO ONE, THE
ADDRESS OF THE CALLING TASK ELEMENT IS SET INTO
EACH SYNCH LOCK IN THE LIST WHICH IS NOT FLAGGED
TO BE SKIPPED, AND CONTROL IS PASSED TO THE
DISPATCHER.
Calls to Other Routines
NONE