FRTBK | Back to Index page

| Prolog Control Block Contents FRTBK 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.

FRTBK Prolog | Top of page

     NAME       : HCPFRTBK
     DESCRIPTION: Function-Related Trace table vector entry
     DSECT      : FRTBK
     FUNCTION   : This control block defines the vector entry which
                  is used to manage a function-related trace table.
     LOCATED BY : HCPFRTAN, anchor of the table.
     CREATED BY : HCPFRTOP - While opening a new function-related trace
                  table.
     UNCREATED BY : HCPFRTCL - When releasing a function-related trace table.
     RELOCATION CONSIDERATIONS : None
     NOTES      : FRTBK must be 64 bytes in length, because it is referenced
                  in a vector page by rounding the token down to a 64 byte
                  boundary.
                  The first invocation of HCPFRTOP allocates an entire page
                  of FRTBKs for the vector chain. When all these FRTBKs are
                  in use, another entire page is allocated by HCPFRTOP.

FRTBK Control Block Content | Top of page

     FRTBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      FRTBK          Function-Related Trace table vector entry
    0000    0 Character   32 FRTNAME        Function-Related trace table name
    0020   32 Signed       8 FRTTOD         TOD of when created
    0028   40 Bitstring    1 FRTSTAT        Entry status
              1... ....      FRTOPEN        X'80' FRTOPEN Entry is in use
              .1.. ....      FRTTIME        X'40' FRTTIME Entry is in timeout
    0029   41 Bitstring    1 FRTSEQNO       Sequence number of entry usage
    002A   42 Signed       2 FRTCOUNT       Count of pages in this table
    002C   44 Address      4 FRTOPENR       Addr of opener of the table
          FRTCURR is used to "lock" the FRTBK so no one else is allowed to
          update it. When the high order bit is on (FRTCURR will contain a
          value of x80000000), it indicates the FRTBK is locked.
    0030   48 Address      4 FRTCURR        Addr of next slot in trace page
                                            to be used.
    0030   48 Address      4 FRTCHAIN       Addr of next FRTBK in chain of
                                            empty vector entries
    0034   52 Signed       4 * (3)          Reserved for IBM use
              00000040       FRTBSIZE       (*-FRTBK) Size in Bytes
              00000008       FRTSIZE        (*-FRTBK+7)/8 Size in Double
                                            words

FRTBK Storage Layout | Top of page

    *** FRTBK - Function-Related Trace table vector entry
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       FRTNAME                         =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  20 |                        FRTTOD                         |
    *     +------+------+-------------+---------------------------+
    *  28 |:STAT |:SEQNO|  FRTCOUNT   |         FRTOPENR          |
    *     +------+------+-------------+---------------------------+
    *  30 |         FRTCURR           |///////////////////////////|
    *     +---------------------------+///////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  40
    *
    *** FRTBK - Function-Related Trace table vector entry

    *** Overlay for FRTCURR in FRTBK
    *
    *     +---------------------------+
    *  30 |         FRTCHAIN          | 34
    *     +---------------------------+
    *
    *** Overlay for FRTCURR in FRTBK

FRTBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    FRTBSIZE       0034 00000040
    FRTCHAIN       0030
    FRTCOUNT       002A
    FRTCURR        0030
    FRTNAME        0000
    FRTOPEN        0028 80
    FRTOPENR       002C
    FRTSEQNO       0029
    FRTSIZE        0034 00000008
    FRTSTAT        0028
    FRTTIME        0028 40
    FRTTOD         0020

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:28:18 EDT.
Copyright IBM Corporation, 1990, 2020