Section: IO Scheduler and block IO Taps (3stap)
Updated: October 2015
Return to Main Contents
probe::ioblock_trace.request - Fires just as a generic block I/O request is created for a bio.
request queue on which this bio was queued.
points to the start sector of the partition structure of the device
i-node number of the mapped file
target block device
bio vector count which represents number of array element (page, offset, length) which make up this I/O request
offset into the bio vector array
- number of segments in this bio after physical address coalescing is performed.
number of bytes transferred
total size in bytes
block device name
points to the device object which contains the partition (when bio structure represents a partition)
name of the probe point
beginning sector for the entire bio
binary trace for read/write request
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
The process makes block I/O request
- SEE ALSO
This document was created by
using the manual pages.
Time: 13:25:45 GMT, October 09, 2015