Addressing the resource control table

The GOVGROUP field of the DXEGOVA control block holds the value of the RESOURCE_GROUP column of Q.RESOURCE_VIEW, the view defined on the resource control table.

All information about the user's resource options is stored in blocks; there is one block for each of the user's resource options you decide to monitor.

The first block defines the first resource option and is stored in the DXEGOVA control block as the DSECT GOVRESCT. The address of this DSECT is defined in the DXEGOVA field GOVRESC. You can establish addressability to the GOVRESC field in your own routine using the address of the GOVRESCT DSECT.

Negative half-word integers in the DSECT represent null values entered for INTVAL, CHARVAL, or FLOATVAL in the Q.RESOURCE_VIEW; zero or positive half-words indicate a value in that column of Q.RESOURCE_VIEW.

The blocks that store the resource control information form a chain in which a pointer in one block points to the beginning of the next block (the next resource option) in the chain. For example, the GOVNEXTR DS statement in the GOVRESCT DSECT, contains the address of the next block in the chain of resource control information. Each block in the chain has a GOVNEXTR DS statement. In the final block, the GOVNEXTR DS statement contains zeros to mark the end of the user's resource control information.

Figure 242 shows a part of the code for the IBM-supplied governor that processes the blocks of resource control information. In this code, GOVRESC points to the GOVRESCT DSECT.

L     R08,GOVOROWS      GET NUMBER OF RESOURCE TABLE ROWS
         LTR   R08,R08           ANY RESOURCE TABLE ROWS?
         BZ    ENDRESST          NO, SKIP RESOURCE INITIALIZATION
         LA    R05,GOVRESC       GET ADDRESS OF 1ST RESOURCE ROW
         USING GOVRESC,R05       BASE RESOURCE RECORD ENTRY
LOOK4RES DS    0H                MAIN LOOP THRU RESOURCE ROWS
         LTR   R05,R05           ANY MORE RESOURCE TABLE ROWS?
         BZ    ENDRESST          NO, END RESOURCE INITIALIZATION

·
·
·

         L     R05,GOVNEXTR      GET ADDRESS ON NEXT RESOURCE ROW
         B     LOOK4RES          BEGIN NEXT ITERATION
ENDRESST DS    OH                -- BRANCH HERE WHEN FINISHED READING ALL ROWS
 
         . . .
         . . .
         . . .
         . . .
 
DXEGOVA  DSECT
 
         .  .  .
         .  .  .
         .  .  .
 
GOVRESC  DS    10XL128           -- RESOURCE CONTROL TABLE
         ORG   GOVRESC
GOVRESCT DSECT                   -- DSECT FOR RESOURCE ROW
         .  .  .
         .  .  .
         .  .  .
GOVNEXTR DS    A                 -- POINTER TO NEXT RESOURCE ROW
         .  .  .
         .  .  .
         .  .  .