probe::ioblock_trace.bounce.3stap - Man Page
Fires whenever a buffer bounce is needed for at least one page of a block IO request.
Synopsis
ioblock_trace.bounce
Values
- name
name of the probe point
- size
total size in bytes
- devname
device for which a buffer bounce was needed.
- bdev
target block device
- q
request queue on which this bio was queued.
- vcnt
bio vector count which represents number of array element (page, offset, length) which makes up this I/O request
- sector
beginning sector for the entire bio
- bytes_done
number of bytes transferred
- rw
binary trace for read/write request
- p_start_sect
points to the start sector of the partition structure of the device
- idx
offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed.
- bdev_contains
points to the device object which contains the partition (when bio structure represents a partition)
- opf
operations and flags
- 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
- ino
i-node number of the mapped file
Context
The process creating a block IO request.
See Also0
tapset::ioblock(3stap)