probe::ioblock_trace.request(3stap) — Linux manual page

PROBE...TRACE(3stap)  IO Scheduler and block IO Taps PROBE...TRACE(3stap)

NAME         top

       probe::ioblock_trace.request - Fires just as a generic block I/O
       request is created for a bio.

SYNOPSIS         top

       ioblock_trace.request

VALUES         top

       bdev
           target block device

       ino
           i-node number of the mapped file

       p_start_sect
           points to the start sector of the partition structure of the
           device

       q
           request queue on which this bio was queued.

       bytes_done
           number of bytes transferred

       devname
           block device name

       size
           total size in bytes

       name
           name of the probe point

       rw
           binary trace for read/write request

       idx
           offset into the bio vector array phys_segments - number of
           segments in this bio after physical address coalescing is
           performed.

       opf
           operations and flags

       vcnt
           bio vector count which represents number of array element
           (page, offset, length) which make up this I/O request

       bdev_contains
           points to the device object which contains the partition (when
           bio structure represents a partition)

       sector
           beginning sector for the entire bio

       flags
           see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK
           1 RW_AHEAD set, and read/write would block BIO_EOF 2
           out-out-bounds error BIO_SEG_VALID 3 nr_hw_seg valid
           BIO_CLONED 4 doesn't own data BIO_BOUNCED 5 bio is a bounce
           bio BIO_USER_MAPPED 6 contains user pages BIO_EOPNOTSUPP 7 not
           supported

CONTEXT         top

       The process makes block I/O request

SEE ALSO         top

       tapset::ioblock(3stap)

COLOPHON         top

       This page is part of the systemtap (a tracing and live-system
       analysis tool) project.  Information about the project can be
       found at ⟨https://sourceware.org/systemtap/⟩.  If you have a bug
       report for this manual page, send it to systemtap@sourceware.org.
       This page was obtained from the project's upstream Git repository
       ⟨git://sourceware.org/git/systemtap.git⟩ on 2025-08-11.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2025-07-24.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
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       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

SystemTap Tapset Reference      April 2025           PROBE...TRACE(3stap)

Pages that refer to this page: tapset::ioblock(3stap)

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