probe::ioblock_trace.request

probe::ioblock_trace.request
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Name

probe::ioblock_trace.request — Fires just as a generic block I/O request is created for a bio.

ioblock_trace.request

vcnt: bio vector count which represents number of array element (page, offset, length) which make up this I/O request
rw: binary trace for read/write request
sector: beginning sector for the entire bio
q: request queue on which this bio was queued.
bdev: target block device
opf: operations and flags
size: total size in bytes
idx: offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed.
devname: block device name
ino: i-node number of the mapped file
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)
name: name of the probe point
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
bytes_done: number of bytes transferred

The process makes block I/O request

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