On an EXEC statement that calls a procedure

If an EXEC statement calls a cataloged or in-stream procedure, the PERFORM parameter overrides the PERFORM parameter on or is added to:

• The EXEC statement named in the procstepname qualifier. The parameter applies only to the named procedure step. The EXEC statement can have as many PERFORM.procstepname parameters as the procedure has steps; each PERFORM parameter must specify a unique procstepname.
• All EXEC statements in the procedure if procstepname is not coded. Then the parameter applies to all steps in the called procedure.