Scheduling and managing SRBs
This information describes how you can schedule an SRB and purge that SRB when you no longer need it. It describes how you use the macros that initiate the running of an SRB routine and provide its recovery. It also describes how you can serialize the processing of an SRB routine and how to transfer control from an SRB to a TCB.
The information includes descriptions of the following macros:
- To schedule an SRB, use either the IEAMSCHD or the SCHEDULE macro. IBM® recommends that you use the IEAMSCHD macro. The program that issues either the IEAMSCHD or SCHEDULE macro is called the scheduling program. The scheduling program can schedule an SRB at different priorities.
- The PURGEDQ macro allows for cleanup of SRB activity.
- The SUSPEND macro suspends the running of an SRB routine until an event occurs.
- The RESUME macro causes the SRB routine to resume running.
- The TCTL macro transfers control from an SRB routine to a task.
The following macros are related to scheduling and managing SRBs:
- The IWMECREA macro allows a program to create an enclave. An enclave is a way to associate related SRBs to be managed and dispatched as a group. A program can schedule an SRB to run in an enclave with the IEAMSCHD macro.
- The IWMEDELE macro allows a program to delete an enclave.
Before you can code the macros, you need to understand the possible cross-memory environments that the SRB routine can begin running in. Also, you need to be aware of some characteristics of SRB routines and some restrictions that the system places on them.