DMKENTKC via CPEXBLOK at midnight if automatic monitoring to spool
file is in effect and it is required to close out the current file
and continue monitoring with a new file. DMKENT satisfies the
nucleus residency requirements of CPEXBLOK entry point and acts as a
stepping stone to Goes to DMKDSP after successful call to DMKMIAKC. DftKMIAKC ---Sets-up a request to invoke a MONITOR CLOSE command in DMKMCCCL. Executes MONITOR processing. CLOSE command and calls DMKMIACC to co.plete DMKMIACC -- Invoked by the
chain the spool
data reduction MONITOR CLOSE command to close the spool file and
file block to the reader of the virtual machine where is to take place. Starts new spool file if appropriate. DMKENTST via TRQBLOK due to previous determination by automatic
monitoring facilities that a MONITOR START SPOOL command should be
issued. This entry satisfies the need for CP nucleus residency and immediately calls the pageable DMKMIAIN. DMKMIAIN ---Suilds a message buffer containing a MONITOR START SPOOL command and
calls D5KMCCCL. Executes MONITOR START SPOOL command. DMKENTST gives control to DMKDSP after successful execution. DMKENTET ---Entered via TRQBLOK due to previous determination by automatic
monitoring facilities that a MONITOR STOP command should be issued at this time. This entry satisfies the need for CP nucleus residency
and immediately calls the pageable DMKMIAEN. DMKKIAEN -- Bulls a message buffer containing a MONITOR STOP command and calls DMKMCCCL. Executes MONITOR STOP command. DMKENTET gives control to the
dispatcher after successful execution. DMKMIAST ----Entered from DMKCPI when it is determined that automatic monitoring
has been requested via the SISMON macro in DMKSYS and that TRQBLOKs should be queued via calls to DKKSCHST to invoke a MONITOR START SPOOL command and a MONITOR STOP command at specified times in the
future. If monitoring is required to start immediately because the
start time bas passed, a CPEXBLOK is built to give control to DMKENTSC, which invokes the DMKMIAIN mechanism described above.
All other DMKMCC, DMKMNI and DMKMIA entry points are used as a result
of the processing of MONITOR commands or special conditions.
Three Class 0 monitor call codes have been reserved for special
purposes. They are used without actually executing monitor calls, but
as a result of MONITOR command processing. They are:
Class Code ---0- 97-- 98
99
Function Write-header record after MONITOR START co.mand Write trailer record after MONITOR STOP com.and Write suspension record when data collection resumes CP Method of Operation and program Organization 1-187

PROGRAM INTERRUPTION PROCESSING For a program interruption received while in supervisor mode (indication of CP module error) and IBTRDR+1 does not indicate MONITOR CALL (X'40') exit to - Ql1K PRG, Send abend message to the system opera tor. DMKDMKPK -- Duip-storage and initiate loading (via IPL). DMKPRGIN ---Par-supervisor state and MONITOR CALL save registers in in DMKPRGPR. DMKPRGMI ---OO-MONITOR CALL interruption processing (DMKMON). For paging exception X'11' and HC mode with translation on call DMKVATEX. DMKVATEX ---Process the exception. DMKPRGIK ---Par-paging exception, x '11' and EC mode with translation off, and
enabled for I/O interrupts and PAGEX on call DftKVATPF. Process the pseudo page fault. QMKPRG, For all other page fault conditions go to DftKPTRAB. DMKPRG, OBSLOCK -- The systei--Iock must be obtained before DftKPTRAB is called. If the
system lock is not immediately available, defer the interrupt and exit to DMKDSPRU. DMK/PTRAN - Bring in the page from the auxiliary device. DMKDSPCH - Exit-to dispatcher. DMKPRG, PRNSTAT ---Par segment-exception X'10' with EC mode on and translation on call DftKVATSX. DKKVATSX ---Process the exception. DMKPRG, PRGSIftI -- For the--segaent exception, X'10' does not follow the above
parametersi process it as an addressing exception. ]2MKPRG, Process X'12' translation exceptions. DMKPRG, PRG01 ---par prIvIleged or operational exception of a virtual machine in
supervisor mode, examine ITRPR+1 if X'01' or '02' call DftKPRVLG. DMKPRVLG ---Process the exception. QMKPRV, For virtual machines in problem mode, store the users new program PSi in VMBLOK VMPSi. DMKPSASV ---When- the program interrupt occurs and the users page 0 is not
resident or the virutal machine is in HC mode, paging is performed. DMKDSPB ---Check the new PSi. DMKPRVLG ---ValIdate the privileged operation indicated in VMINST and perform the
service.
1-188 IBM VM/370 System Logic and Problem Determination--Volume 1