DCHBK

Prolog  

Control Block Contents  
   DCHBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

DCHBK Prolog

 NAME       : HCPDCHBK
 DESCRIPTION: Diagnose Control Header
 DSECT      : DCHBK
 FUNCTION   : The Diagnose Control Header serializes use of the
              diagnose control block locator array, as well as
              locates the diagnose control block locator array.
 LOCATED BY : SYSCM.SYSDCHBK
 CREATED BY : HCPHVAIN
 DELETED BY : None.
 REFERENCES : None.
 SERIALIZED : The DCHBK is created during system initialization;
              no further serialization is required.
              The DCHLOCK is obtained exclusive in order to
              serialize additions to the array of addresses of
              DGNBKs.  Since an address in the array is never
              deleted, there is no conflict between searching and
              adding.  Therefore, there is no need to obtain the
              DCHLOCK for searching.
 RELOCATION CONSIDERATIONS : None

DCHBK Control Block Content

DCHBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      DCHBK          Diagnose Control Header
0000    0 Dbl-Word     8 DCHLOCK (3)    Lock for serializing actions on
                                        the DCHDGNIX array of addresses.
0018   24 Address      4 DCHDGNIX       Address of the array of addresses
                                        of DGNBKs.
001C   28 Address      4 *              Reserved
0020   32 Dbl-Word     8 DCH$END (0)    The end

DCHBK Storage Layout

          
*** DCHBK - Diagnose Control Header
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       DCHLOCK                         =
*     |                                                       |
*     +---------------------------+---------------------------+
*  18 |         DCHDGNIX          |///////////////////////////|
*     +---------------------------+---------------------------+
*
*** DCHBK - Diagnose Control Header

DCHBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
DCH$END        0020
DCHDGNIX       0018
DCHLOCK        0000