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

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

NAME

       probe::ioblock.request - Fires whenever making a generic block I/O request.

SYNOPSIS

       ioblock.request

VALUES

       None

DESCRIPTION

       name - name of the probe point devname - block device name ino - i-node number of the mapped file 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 hw_segments
       - number of segments after physical and DMA remapping hardware 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