1PROBE::IOBLOCK.REQ(3stap)IO Scheduler and block IO TapsPROBE::IOBLOCK.REQ(3stap)
2
3
4

NAME

6       probe::ioblock.request - Fires whenever making a generic block I/O
7       request.
8

SYNOPSIS

10       ioblock.request
11

VALUES

13       ino
14           i-node number of the mapped file
15
16       devname
17           block device name
18
19       bdev
20           target block device
21
22       vcnt
23           bio vector count which represents number of array element (page,
24           offset, length) which make up this I/O request
25
26       flags
27           see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1
28           RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds
29           error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data
30           BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user
31           pages BIO_EOPNOTSUPP 7 not supported
32
33       idx
34           offset into the bio vector array
35
36       size
37           total size in bytes
38
39       p_start_sect
40           points to the start sector of the partition structure of the device
41
42       hw_segments
43           number of segments after physical and DMA remapping hardware
44           coalescing is performed
45
46       phys_segments
47           number of segments in this bio after physical address coalescing is
48           performed
49
50       bdev_contains
51           points to the device object which contains the partition (when bio
52           structure represents a partition)
53
54       rw
55           binary trace for read/write request
56
57       sector
58           beginning sector for the entire bio
59
60       name
61           name of the probe point
62
63       opf
64           operations and flags
65

CONTEXT

67       The process makes block I/O request
68

SEE ALSO

70       tapset::ioblock(3stap)
71
72
73
74SystemTap Tapset Reference       November 2019       PROBE::IOBLOCK.REQ(3stap)
Impressum