Red Hat Training

A Red Hat training course is available for Red Hat Enterprise Linux

probe::ioblock_trace.request


Name

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

Synopsis

ioblock_trace.request 

Values

q
request queue on which this bio was queued.
size
total size in bytes
idx
offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed.
vcnt
bio vector count which represents number of array element (page, offset, length) which make up this I/O request
bdev
target block device
p_start_sect
points to the start sector of the partition structure of the device
ino
i-node number of the mapped file
rw
binary trace for read/write request
name
name of the probe point
sector
beginning sector for the entire bio
bdev_contains
points to the device object which contains the partition (when bio structure represents a partition)
devname
block device name
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
bytes_done
number of bytes transferred

Context

The process makes block I/O request