PFPRQ | Back to Index page

| Prolog Control Block Contents PFPRQ 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.

PFPRQ Prolog | Top of page

     NAME       : HCPPFPRQ
     DESCRIPTION: Prefetch PPGMBK Request block
     DSECT      : PFPRQ
     FUNCTION   : Prefetch PPGMBK Request block
     LOCATED BY : FRMPTEG  field of the FRMTE(s) corresponding to the
                  PTRM page to be prefetched
                  PIRSAVE1 field of containing PFPRQ, PFPPIRBK
     CREATED BY : HCPPFPOR - Open Prefetch Pageable PGMBKs Request
     DELETED BY : HCPPFPCR - Close Prefetch Pageable PGMBKs Request
     SERIALIZED : Fields which are used only during front end scan and
                  selection processing are serialized simply by being
                  task local.  Fields shared with the back end processing
                  are serialized by CS*.
     RELOCATION CONSIDERATIONS : none
     COMMENTS   : The PFPRQ must reside on a doubleword boundary.  The
                  PFPRQ contains an ITRBK and a PIRBK, so any module
                  which uses PFPRQ must also COPY the ITRBK and PIRBK.
                  The PFPRQ mapping contains pointers, virtual address
                  cursors, queue headers, and counts necessary for managing
                  an individual PPGMBK prefetch request.  A prefetch
                  request is for a specific private space and does not
                  span multiple spaces or users.
                  The PFPRQ mapping also contains an ITRBK for using the DAT
                  table iterator HCPHDITR for scanning the DAT tables, and a
                  PIRBK for managing paging interrupt return routing for
                  prefetch I/O (so that they do not have to be obtained and
                  released dynamically "in the loop").

PFPRQ Control Block Content | Top of page

     PFPRQ DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      PFPRQ          Prefetch PPGMBK Request block
          Pointers
    0000    0 Signed       4 PFPVMDBK       Owning User base VMDBK address
    0004    4 Signed       4 PFPASCBK       Owning User ASCBK address
          Prefetch cursors / limits (virtual addresses):
    0008    8 Address      8 PFPRQCUR       Requestor's processing cursor
    0010   16 Address      8 PFPRQEND       Requestor's ending vaddr
    0018   24 Address      8 PFPSCCUR       Prefetch scan cursor (next to
                                            scan)
    0020   32 Address      8 PFPSCTAR       Prefetch "scan to" target
    0028   40 Address      8 PFPIOCUR       Prefetch I/O cursor (last read
                                            issued)
    0030   48 Address      8 PFPIOHIW       Prefetch I/O complete "high water
                                            mark" by vaddr
          Prefetch buffer queue header and count:
          Terminated by StgEOQ in FRMFPNTG of last FRMTE on queue.
    0038   56 Address      8 PFPBUFFQ       Next (first) FRMTE on prefetch
                                            avail frame pair queue or
                                            negative (StgEoQ) if empty.
                                            Queued by fwd ptr of 1st FRMTEs
                                            of pairs. Queue terminated by
                                            StgEOQ in FRMFPNTG.
    0040   64 Signed       4 PFPBUFFC       Count of buffers on queue
    0044   68 Signed       4 * (0)          Reserved for IBM use
          Prefetch I/O block multi-read PPGMBKs queue:
          Terminated by StgEOQ in FRMFPNTG of last FRMTE on queue.
    0048   72 Address      8 PFPIOQ_F       First FRMTE on I/O queue being
                                            built
    0050   80 Address      8 PFPIOQ_L       Last FRMTE on I/O queue being
                                            built
    0058   88 Signed       4 PFPIOQ_C       Count of PPGMBKs (by 1st FRMTE of
                                            pair) currently on I/O queue
          Historical and state tracking counts - primarily for debug
          and verification, global monitored version of some counts
          kept in the RSMBK for monitor.
          Historical counts:
    005C   92 Signed       4 PFPSTESC       STEs scanned
    0060   96 Signed       4 PFPIOI         Prefetch I/Os issued by PPGMBKs
    0064  100 Signed       4 PFPIOCLS       Prefetch I/Os issued by PAGMR
                                            calls
    0068  104 Signed       4 PFPIOC         Prefetch I/Os completed
    006C  108 Signed       4 PFPPTRRV       Prefetch PTRM revalidations
                                            completed
    0070  112 Signed       4 PFPSTERV       Prefetch STE revalidations
                                            completed
    0074  116 Signed       4 PFPOMISS       Paged-out PPGMBKs found by
                                            mainline path of this requestor
          Outstanding state counts:
    0078  120 Signed       4 PFPPFOUT       Overall outstanding PGMBK
                                            prefetches
    007C  124 Signed       4 PFPIOSI        Prefetch I/Os issued, nothing
                                            back
    0080  128 Signed       4 PFPIOS1        Prefetch I/Os half done, half not
    0084  132 Signed       4 PFPIOSC        Prefetch I/Os fully completed,
                                            PTRM revalidation pending
          ITRBK for use by prefetch task:
    0088  136 Signed       8 * (0)          dw bdry
    0088  136 Bitstring   96 PFPITRBK       An ITRBK for prefetch
          PIRBK for use by prefetch task:
    00E8  232 Signed       8 * (0)          dw bdry
    00E8  232 Bitstring   40 PFPPIRBK       A PIRBK for prefetch
    0110  272 Signed       4 PFP$END (0)    End of control block
              00000110       PFPLEN         *-PFPRQ Length of PFPRQ in bytes
              00000022       PFPSIZE        (PFPLEN+7)/8 Size of PFPRQ in
                                            doublewords

PFPRQ Storage Layout | Top of page

    *** PFPRQ - Prefetch PPGMBK Request block
    *
    *     +---------------------------+---------------------------+
    *   0 |         PFPVMDBK          |         PFPASCBK          |
    *     +---------------------------+---------------------------+
    *   8 |                       PFPRQCUR                        |
    *     +-------------------------------------------------------+
    *  10 |                       PFPRQEND                        |
    *     +-------------------------------------------------------+
    *  18 |                       PFPSCCUR                        |
    *     +-------------------------------------------------------+
    *  20 |                       PFPSCTAR                        |
    *     +-------------------------------------------------------+
    *  28 |                       PFPIOCUR                        |
    *     +-------------------------------------------------------+
    *  30 |                       PFPIOHIW                        |
    *     +-------------------------------------------------------+
    *  38 |                       PFPBUFFQ                        |
    *     +---------------------------+---------------------------+
    *  40 |         PFPBUFFC          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  48 |                       PFPIOQ_F                        |
    *     +-------------------------------------------------------+
    *  50 |                       PFPIOQ_L                        |
    *     +---------------------------+---------------------------+
    *  58 |         PFPIOQ_C          |         PFPSTESC          |
    *     +---------------------------+---------------------------+
    *  60 |          PFPIOI           |         PFPIOCLS          |
    *     +---------------------------+---------------------------+
    *  68 |          PFPIOC           |         PFPPTRRV          |
    *     +---------------------------+---------------------------+
    *  70 |         PFPSTERV          |         PFPOMISS          |
    *     +---------------------------+---------------------------+
    *  78 |         PFPPFOUT          |         PFPIOSI           |
    *     +---------------------------+---------------------------+
    *  80 |         PFPIOS1           |         PFPIOSC           |
    *     +---------------------------+---------------------------+
    *  88 |                                                       |
    *     =                       PFPITRBK                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  E8 |                                                       |
    *     =                       PFPPIRBK                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *
    *** PFPRQ - Prefetch PPGMBK Request block

PFPRQ Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    PFP$END        0110
    PFPASCBK       0004
    PFPBUFFC       0040
    PFPBUFFQ       0038
    PFPIOC         0068
    PFPIOCLS       0064
    PFPIOCUR       0028
    PFPIOHIW       0030
    PFPIOI         0060
    PFPIOQ_C       0058
    PFPIOQ_F       0048
    PFPIOQ_L       0050
    PFPIOSC        0084
    PFPIOSI        007C
    PFPIOS1        0080
    PFPITRBK       0088
    PFPLEN         0110 00000110
    PFPOMISS       0074
    PFPPFOUT       0078
    PFPPIRBK       00E8
    PFPPTRRV       006C
    PFPRQCUR       0008
    PFPRQEND       0010
    PFPSCCUR       0018
    PFPSCTAR       0020
    PFPSIZE        0110 00000022
    PFPSTERV       0070
    PFPSTESC       005C
    PFPVMDBK       0000

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:29:36 EDT.
Copyright IBM Corporation, 1990, 2020