LOCBK

Prolog  

Control Block Contents  
   LOCBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

LOCBK Prolog

 Name       : HCPLOCBK
 Description: C System Services Lock block
 DSECT      : LOCBK
 Function   : C System Services Lock block used to describe the
              spin lock used by platform specific C Services
 Located by : Passed as argument on lock, unlock, testLock
              and eventWait services
 Created by : allocateLock service
 Deleted by : deallocateLock service
 Serialized : CP lock routines
 Notes      : This COPY file was modeled after HCPSYNBK so the
              existing CP spin lock routines could be utilized.

LOCBK Control Block Content

LOCBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      LOCBK          C System Services Lock block
0000    0 Dbl-Word     8 LOCSLOCK (3)   Spin lock
0018   24 Dbl-Word     8 LOCTHRED       Pointer to thread which holds
                                        lock
          00000020       LOCBSIZE       *-LOCBK size in bytes
          00000004       LOCSIZE        (*-LOCBK+7)/8 size in double
                                        words
0000    0 Signed       4 LOCLOCK        Lock word (0 = not held, else CPU
                                        id)
0004    4 Signed       4 LOCHOLDR       Macro address last obtaining this
                                        lock
0008    8 Dbl-Word     8 LOCTIME        Elapsed spin time on this lock
0010   16 Signed       4 LOCCOUNT       Number of spins on this lock
0014   20 Signed       4 *              Reserved for future IBM use

LOCBK Storage Layout

          
*** LOCBK - C System Services Lock block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       LOCSLOCK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  18 |                       LOCTHRED                        |
*     +-------------------------------------------------------+
*  20
*
*** LOCBK - C System Services Lock block
          
*** Overlay for LOCSLOCK in LOCBK
*
*     +---------------------------+---------------------------+
*   0 |         LOCLOCK           |         LOCHOLDR          |
*     +---------------------------+---------------------------+
*   8 |                       LOCTIME                         |
*     +---------------------------+---------------------------+
*  10 |         LOCCOUNT          |///////////////////////////|
*     +---------------------------+---------------------------+
*  18
*
*** Overlay for LOCSLOCK in LOCBK

LOCBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
LOCBSIZE       0018 00000020
LOCCOUNT       0010
LOCHOLDR       0004
LOCLOCK        0000
LOCSIZE        0018 00000004
LOCSLOCK       0000
LOCTHRED       0018
LOCTIME        0008