An ADS user written built-in function (BIF) does an SVC Call to do a write to SMF.
Can we do SVC calls from User BIFs when running with zIIP?
Release : 19.0
In general we do not support the issuing of SVC calls from user written programs as this can cause the CV to hang or abend.
There is an additional problem when running with ZIIP=Y because the ADS runtime code, including user BIFs, will execute on zIIP processors under an SRB rather than on a TCB.
In z/OS it is illegal to issue an SVC in SRB mode, you have to be in TCB mode. Issuing an SVC from an SRB will cause the IDMS CV to abort with an S0F8-4 abend code.
This means that if running with zIIP you cannot issue SVC calls from ADS User BIFs.
To get around the problem you will have to do one of the following:
Note the considerations for user mode exits in section Installing Numbered Exits in the System:
The routine can access only the storage pages associated with it unless storage protection has been disabled at the system or the program level.
The exit routine:
Runs as a program under the DC/UCF nucleus.
Uses standard IBM calling conventions (except that no save area is passed in register 13). The exit is called by a #LINK statement.
Cannot process register 15 Return codes.
Here is a sample exit:
UX258 TITLE 'UX258 -- ISSUE SVC'
L R1,4(R1) << R1 point to passed parameters
... << additional code
WORK DSECT << passed ISA
WORK_1 DS 18F