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¶
None
DESCRIPTION¶
name - name of the probe point
q - request queue on which this bio
was queued.
devname - device for which a buffer bounce was needed.
ino - i-node number of the mapped file
bytes_done - number of
bytes transferred
sector - beginning sector for the entire bio
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
rw - binary trace for read/write request
vcnt - bio
vector count which represents number of array element (page, offset, length)
which makes up this I/O request
idx - offset into the bio vector array
phys_segments - number of segments in this bio after physical address
coalescing is performed.
size - total size in bytes
bdev -
target block device
bdev_contains - points to the device object which
contains the partition (when bio structure represents a partition)
p_start_sect - points to the start sector of the partition structure of
the device
CONTEXT¶
The process creating a block IO request.