Name

probe::ioblock_trace.bounce — Fires whenever a buffer bounce is needed for at least one page of a block IO request.

Synopsis

ioblock_trace.bounce 

Values

ino

i-node number of the mapped file

bytes_done

number of bytes transferred

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

name

name of the probe point

bdev_contains

points to the device object which contains the partition (when bio structure represents a partition)

size

total size in bytes

devname

device for which a buffer bounce was needed.

sector

beginning sector for the entire bio

rw

binary trace for read/write 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

bdev

target block device

idx

offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed.

p_start_sect

points to the start sector of the partition structure of the device

Context

The process creating a block IO request.