IEAAFFN — Assign processor affinity for encryption or decryption

Call IEAAFFN when the only function performed by your program is to encrypt or decrypt data. Encryption and decryption take place on processors that have Integrated Cryptographic Features (ICRFs) associated with them. IEAAFFN assigns a program affinity to processors with an ICRF; that is, IEAAFFN makes sure the system runs your program on a processor that has an ICRF associated with it.

You do not have to use the IEAAFFN service to ensure the system runs a program on a processor with an ICRF; the system ensures that automatically. However, you can avoid some of the system overhead involved in the selection process by using the IEAAFFN service. IBM® recommends that you use the service in programs whose only function is encryption or decryption.

Note: When you use this service to either establish or remove processor affinity for a program, the program permanently loses any processor affinity that the system programmer assigned to it in the SCHEDxx member of SYS1.PARMLIB.

Code the CALL following the syntax of the high level language you are using and specifying all parameters in the order shown below.

CALL statement	Parameters
CALL IEAAFFN	(feature ,operation_type ,return_code)

The parameters are explained as follows:

feature

Specifies the feature required by your program. Specify CRYPTO to indicate an ICRF.

Define feature as character data of length 10. Pad the string on the right with 4 blanks.

,operation_type

Specifies the type of action you want to take. The types are:

GRANT: Establish affinity for the program to processors with an ICRF.
REMOVE: Remove affinity for the program to processors with an ICRF.
Note: After you issue a REMOVE request, the program has no processor affinity; it can run on any processor.

Define operation_type as character data of length 6. If you specify GRANT, pad the string on the right with 1 blank.

,return_code

When IEAAFFN completes, return_code contains the return code from the service. The return code value is also in register 15.

Define return_code as integer data of length 4. The return codes are explained under Return codes.