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Prolog 
Control Block Contents 
   LOCBK DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.


  LOCBK Prolog Top of page
 
 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
 RELOCATION CONSIDERATIONS : None
 NOTES      : This COPY file was modeled after HCPSYNBK so the
              existing CP spin lock routines could be utilized.
 
 
  LOCBK Control Block Content Top of page
 

 LOCBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure LOCBK C System Services Lock block 0000 0 Dbl-Word 8 LOCSLOCK (6) Spin lock 0030 48 Dbl-Word 8 LOCTHRED Pointer to thread which holds lock 00000038 LOCBSIZE *-LOCBK size in bytes 00000007 LOCSIZE (*-LOCBK+7)/8 size in double words 0000 0 Dbl-Word 8 LOCLOCK (0) First doubleword of the lock area 0000 0 Bitstring 1 LOCSTATE Lock word (0 = not held, else CPU id) 0001 1 Bitstring 1 * Reserved for future IBM use 0002 2 Signed 2 LOCSHCNT Shared hold count 0004 4 Signed 2 LOCSEQ Lock sequence number 0006 6 Signed 2 LOCHCPAD CPU addr of lock holder End of LOCLOCK area 0008 8 Signed 2 LOCSWCNT Shared wait count 000A 10 Signed 2 LOCXWCNT Exclusive wait count 000C 12 Signed 4 LOCSSCNT Shared spin count 0010 16 Dbl-Word 8 LOCSTIME Total elapsed shared spin time 0018 24 Signed 4 LOCHOLDR Address of holder of this lock 001C 28 Signed 4 LOCXSCNT Exclusive spin count 0020 32 Dbl-Word 8 LOCXTIME Total elapsed exclusive spin time 0028 40 Signed 2 LOCPLSDS Displacement of shared lock holder field into the PLSBK 002A 42 Signed 2 * Reserved for future IBM use 002C 44 Signed 4 * Reserved for future IBM use
 
 
  LOCBK Storage Layout Top of page
 
          
*** LOCBK - C System Services Lock block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       LOCSLOCK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  30 |                       LOCTHRED                        |
*     +-------------------------------------------------------+
*  38
*
*** LOCBK - C System Services Lock block
          
*** Overlay for LOCSLOCK in LOCBK
*
*     +------+------+-------------+-------------+-------------+
*   0 |:STATE|//////|  LOCSHCNT   |   LOCSEQ    |  LOCHCPAD   |
*     +------+------+-------------+-------------+-------------+
*   8 |  LOCSWCNT   |  LOCXWCNT   |         LOCSSCNT          |
*     +-------------+-------------+---------------------------+
*  10 |                       LOCSTIME                        |
*     +---------------------------+---------------------------+
*  18 |         LOCHOLDR          |         LOCXSCNT          |
*     +---------------------------+---------------------------+
*  20 |                       LOCXTIME                        |
*     +-------------+-------------+---------------------------+
*  28 |  LOCPLSDS   |/////////////|///////////////////////////|
*     +-------------+-------------+---------------------------+
*  30
*
*** Overlay for LOCSLOCK in LOCBK
 
 
  LOCBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
LOCBSIZE       0030 00000038
LOCHCPAD       0006
LOCHOLDR       0018
LOCLOCK        0000
LOCPLSDS       0028
LOCSEQ         0004
LOCSHCNT       0002
LOCSIZE        0030 00000007
LOCSLOCK       0000
LOCSSCNT       000C
LOCSTATE       0000
LOCSTIME       0010
LOCSWCNT       0008
LOCTHRED       0030
LOCXSCNT       001C
LOCXTIME       0020
LOCXWCNT       000A
 
This information is based on z/VM 6.3.0 Last updated on 22 May 2013 at 13:54:51 EDT.
Copyright IBM Corporation, 1990, 2013