Programming Interface Information: This information is NOT intended to be
used as Programming Interfaces of VM/ESA. It is to be used for diagnosis only.

DSVBK

Prolog  

Control Block Contents  

DSVBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

DSVBK Prolog

 Name       : HCPDSVBK
 Description: DiSpatch Vector BlocK
 DSECT      : DSVBK
 Function   : The DSVBK maps the format of a Processor Local
              Dispatch Vector (PLDV).  There is one PLDV for each
              real CPU, plus an additional one to contain Master-
              Only work.  This DSECT maps the storage defined in
              the module HCPDSV.
 Located by : HCPDSVMS is the address of the Master-Only PLDV.
              HCPDSVST is the starting address of the other PLDVs.
              They are contiguous in storage.
 Created by : The PLDVs are DCed in module HCPDSV.
 Deleted by : Never deleted

 

DSVBK Control Block Content


DSVBK DSECT

Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure DSVBK DiSpatch Vector BlocK Format of the header: 00000000 DSVHEADR * Base value to be used when referencing the PLDV header. 0000 0 Bitstring 1 DSVHDWKB Byte of Work Bits 1... .... DSVDSCAN X'80' A Steal Task may need to be started 0001 1 Bitstring 1 DSVHDFLG Flag byte for PLDV status 1... .... DSVHDOFL X'80' Set when PLDV has "overflowed" .1.. .... DSVTIDLE X'40' Set to indicate that a scan should be made of the test-idle users by HCPDSP. ...1 .... DSVIMBAL X'10' Possible processor workload imbalance .... 1... DSVNOPTL X'08' We could not obtain the PTIL lock for any of the VMDBKs in the master-only PLDV. 0002 2 Address 1 DSVHDFRE Anchor of the "entries not in use" queue. 0003 3 Address 1 DSVHDWRK Anchor of the "entries in use" queue. 0004 4 Bitstring 2 DSVBR14 THIS IS REALLY THE FOLLOWING: *CMNT** BR R14 INSTRUCTION TO CAUSE A READ- ONLY REQUEST OF STORAGE. 0006 6 Address 1 DSVLSTEN Last entry in the PLDV 0007 7 Address 1 * Reserved for future IBM use 0008 8 Signed 4 DSVLOREJ Lowest-value (best) priority which was rejected from this PLDV 000C 12 Signed 2 DSVUSERC User count - number of VMDBKS in this PLDV 000E 14 Signed 2 * Reserved for future IBM use 00000010 DSVHDLEN *-DSVHEADR Length in bytes of the PLDV header. Format of each entry: 00000010 DSVENTRY * Base value to be use when referencing a PLDV entry. 0010 16 Address 0 DSVVMDBK Bits 0 to 19 of the user's VMDBK address. Bits 20 to 31 are known to be zero and need not be stored in the Vector entry. 1... .... DSVINUSE X'80' High-order bit is set when the PLDV entry is "in use", whenever the entry is in the chain starting from DSVHDWRK. 0012 18 Bitstring 0 DSVFLAGS A flag nibble .... 1... DSVNOSTL X'08' Set when work MUST not be stolen, in order to respect VMDBK's affinity requirements 0013 19 Address 1 DSVFPNT Forward pointer to next entry in queue. Zero if this is the last entry. 0014 20 Signed 4 DSVPRIOR A representation of this VMDBK's priority in the dispatch list. The value in this field is a function of the VMDBK's VMDDPRTY. 00000008 DSVENTLN *-DSVENTRY Length in bytes of a PLDV entry 0000000E DSVMAXUS 14 Maximum number of users in a PLDV 00000080 DSVLEN DSVHDLEN+DSVMAXUS*DSVENTLN Length in bytes of a PLDV. 00000010 DSVSIZE (DSVLEN+7)/8 Size in doublewords of a PLDV

 

DSVBK Storage Layout

*** DSVBK - DiSpatch Vector BlocK
*
*     +------+------+------+------+-------------+------+------+
*   0 |:HDWKB|:HDFLG|:HDFRE|:HDWRK|  DSVBR14    |:LSTEN|//////|
*     +------+------+------+------+-------------+------+------+
*   8 |         DSVLOREJ          |  DSVUSERC   |/////////////|
*     +---------------------------+-------------+-------------+
*  10 |                                                       |
*     =                       DSVVMDBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*
*** DSVBK - DiSpatch Vector BlocK
*** Overlay for DSVVMDBK+2 in DSVBK
*
*                   +------+------+---------------------------+
*  10 ...        12 |:FLAGS|:FPNT |         DSVPRIOR          |
*                   +------+------+---------------------------+
*  18
*
*** Overlay for DSVVMDBK+2 in DSVBK

 

DSVBK Cross Reference

(contains links to field and bit definitions)
Symbol         Dspl Value
-------------- ---- -----

DSVBR14 0004

DSVDSCAN 0000 80

DSVENTLN 0014 00000008

DSVENTRY 000E 00000010

DSVFLAGS 0012

DSVFPNT 0013

DSVHDFLG 0001

DSVHDFRE 0002

DSVHDLEN 000E 00000010

DSVHDOFL 0001 80

DSVHDWKB 0000

DSVHDWRK 0003

DSVHEADR 0000 00000000

DSVIMBAL 0001 10

DSVINUSE 0010 80

DSVLEN 0014 00000080

DSVLOREJ 0008

DSVLSTEN 0006

DSVMAXUS 0014 0000000E

DSVNOPTL 0001 08

DSVNOSTL 0012 08

DSVPRIOR 0014

DSVSIZE 0014 00000010

DSVTIDLE 0001 40

DSVUSERC 000C

DSVVMDBK 0010


This information is based on VM/ESA 2.4.0.
Last updated on 3 Aug 1999 at 11:53:15 EDT.
Copyright IBM Corporation, 1990, 1999