Type ASSEMBLE
Source Lines : 1,302
Fixes Applied : 14
Most Recent Version : Monday, January 22, 1979
Last Fix ID : [R13026DK]
Module
DMKMCH
Function
THE FUNCTION OF THIS ROUTINE IS TO DETERMINE THE SEVERITY OF
A MACHINE CHECK AND ATTEMPT TO CORRECT THE MALFUNCTION.
DIAGNOSTIC MESSAGES FOR THE SYSTEM OPERATOR, AND ERROR DATA
FOR THE F.E. PERSONNEL USE WILL BE PRODUCED AS OUTPUT.
Attributes
RESIDENT,ENTERED DIRECTLY VIA MC NEW PSW
Operation
DMKMCHIN
1. RECEIVES CONTROL WHEN A MACHINE CHECK INTERRUPT CAUSES THE
MC NEW PSW TO BE LOADED
2. INITALLY DISABLES BOTH HARD AND SOFT MACHINE CHECKS WHILE
DETERMINING THE SEVERITY OF THE ERROR. WHEN IT IS DETERMINED
THAT THE ERROR IS NOT ONE THAT REQUIRES SYSTEM TERMINATION
THEN HARD MACHINE CHECK INTERRUPTS WILL BE RE-ENABLED.
3. IF THE ERROR IS ONE THAT SHOULD TERMINATE SYSTEM OPERATION,
AND THE SYSTEM IS IN ATTACHED PROCESSOR MODE, CONTROL WILL
BE GIVEN TO DMKMCTPT, THE PROCESSOR TERMINATION ROUTINE FOR
ATTACHED PROCESSING. FOR UNIPROCESSING MODE,
A DIRECT I/O OPERATION TO THE SYSTEM OPERATOR INFORMING
HIM OF THE FAILURE, AND RECOMMENDED ACTION TO BE PERFORMED
WILL BE DONE IF CONSOLE IS ACCESSABLE, FOLLOWED BY DMKMCH
PLACING THE SYSTEM IN A DISABLED WAIT STATE.
IF THE ERROR AFFECTS ONLY THE VIRTUAL USER, THE ERROR WILL
BE RECORDED AND A MESSAGE WILL BE SENT TO THE AFFECTED USER.
THE VIRTUAL MACHINE WILL BE RESET AND PLACED IN
CP CONSOLE FUNCTION MODE. THE VIRTUAL= REAL USER
WILL BE TERMINATED AND LOGGED OFF IF A STORAGE ERROR
HAS OCCURRED.
4. BEFORE ANY SYSTEM FUNCTIONS ARE USED, THE MACHINE CHECK
HANDLER WILL ATTEMPT TO GET THE GLOBAL SYSTEM LOCK. IF THE
LOCK IS UNAVAILABLE, CPMCHLK WILL BE SET TO ALLOW PROCESSING
TO CONTINUE WHEN THE LOCK IS AVAILABLE. DMKMCHSE WILL RECEIVE
CONTROL FROM THE DISPATCHER WHEN CPMCHLK IS ON.
IF ANY MACHINE CHECKS OCCUR DURING THIS PROCESSING, THEY
WILL BE VIEWED AS RECURSIVE MACHINE CHECKS.
CPMCHLK PREVENTS THE DISPATCHER FROM DISPATCHING ANY
NEW WORK FOR THAT PROCESSOR UNTIL THE MACHINE CHECK
INTERRUPT IS HANDLED.
5. ON SOFT ERRORS THE SYSTEM OPERATOR WILL BE INFORMED, A TEST
WILL BE MADE TO DETERMINE IF ANY SOFT ERROR THRESHOLDS HAVE
BEEN EXCEEDED, THE ERROR WILL BE RECORDED, AND CONTROL WILL
BE RETURNED TO THE INTERRUPTED PROGRAM.
6. ON SPF AND MULTI-BIT ECC ERRORS AN ANALYSIS WILL BE MADE TO
DETERMINE IF THE DAMAGE CAN BE REFRESHED OR NOT. ADDITIONALLY
A FUNCTIONAL TEST OF THE FAILING FRAME OF STORAGE WILL BE
PERFORMED TO DETERMINE IF THAT FRAME SHOULD BE REMOVED FROM
SYSTEMS USE.
7. A THRESHOLD COUNT FOR ALL SOFT MACHINE CHECKS WILL
BE KEPT AND WHEN THE THRESHOLD COUNT EXCEED THE
MAX. VALUE, THE SOFT MACHINE CHECKS WILL BE DISABLE
FOR SOFT INTERRUPTS FOR BOTH PROCESSORS.
8. THE SYSTEM OPERATOR WILL BE INFORMED OF ANYTIME
THE MACHINE IS DISABLED FOR SOFT MACHINE CHECKS.
Calls to Other Routines
DMKIOEMC - TO RECORD FORMATTED MACHINE CHECK RECORDS
GPR6 = FORMATTED MACHINE CHECK RECORD ADDRESS
GPR7 = LENGTH OF MACHINE CHECK RECORD
DMKQCNWT - TO SEND MESSAGES TO A VIRTUAL MACHINE AND THE
SYSTEM OPERATOR
DMKPTRFT - TO PURGE DEFECTIVE PAGE IN STORAGE
DMKFREE - TO GET STORAGE FOR CPEXBLOKS
DMKSTKOP - TO STACK A CPEXBLOK FOR THE OTHER PROCESSOR
DMKPGSPO - TO RELEASE USER'S VIRTUAL STORAGE
DMKCFMBK - TO PUT USER IN CONSOLE FUNCTION MODE
DMKCFPRR - TO RESET VIRTUAL MACHINE
DMKOPRWT - TO WRITE EMERGENCY MESSAGE TO SYSTEM OPERATOR
DMKMCTPT - TERMINATE THE AILING PROCESSOR
DMKMCTST - TERMINATE THE SYSTEM