probe::ioblock_trace.request
Fires just as a generic block I/O request is created for a bio.
- Provided by: systemtap-doc (Version: 4.2-3ubuntu0.1)
- Source: systemtap
- Report a bug
SYNOPSIS
ioblock_trace.request
VALUES
devname
block device name
ino
i-node number of the mapped file
idx
offset into the bio vector array phys_segments -
number of segments in this bio after physical address coalescing is
performed.
bytes_done
number of bytes transferred
size
total size in bytes
bdev
target block device
vcnt
bio vector count which represents number of array element
(page, offset, length) which make up this I/O request
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
p_start_sect
points to the start sector of the partition structure of
the device
bdev_contains
points to the device object which contains the partition
(when bio structure represents a partition)
q
request queue on which this bio was queued.
rw
binary trace for read/write request
sector
beginning sector for the entire bio
name
name of the probe point
opf
operations and flags
CONTEXT
The process makes block I/O request