trusty (3) probe::ioblock_trace.request.3stap.gz

Provided by: systemtap-doc_2.3-1ubuntu1.4_all bug

NAME

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

SYNOPSIS

       ioblock_trace.request

VALUES

       None

DESCRIPTION

       name - name of the probe point q - request queue on which this bio was queued.  devname - block device
       name ino - i-node number of the mapped file bytes_done - number of bytes transferred 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

       rw - binary trace for read/write request vcnt - bio vector count which represents number of array element
       (page, offset, length) which make up this I/O request idx - offset into the bio vector array
       phys_segments - number of segments in this bio after physical address coalescing is performed.  size -
       total size in bytes bdev - target block device bdev_contains - points to the device object which contains
       the partition (when bio structure represents a partition) p_start_sect - points to the start sector of
       the partition structure of the device

CONTEXT

       The process makes block I/O request