1PROBE::IOBLOCK_TRACE(3staIpO)Scheduler and block IO TaPpRsOBE::IOBLOCK_TRACE(3stap)
2
3
4
6 probe::ioblock_trace.bounce - Fires whenever a buffer bounce is needed
7 for at least one page of a block IO request.
8
10 ioblock_trace.bounce
11
13 size
14 total size in bytes
15
16 p_start_sect
17 points to the start sector of the partition structure of the device
18
19 vcnt
20 bio vector count which represents number of array element (page,
21 offset, length) which makes up this I/O request
22
23 opf
24 operations and flags
25
26 bdev_contains
27 points to the device object which contains the partition (when bio
28 structure represents a partition)
29
30 ino
31 i-node number of the mapped file
32
33 rw
34 binary trace for read/write request
35
36 sector
37 beginning sector for the entire bio
38
39 name
40 name of the probe point
41
42 q
43 request queue on which this bio was queued.
44
45 bdev
46 target block device
47
48 idx
49 offset into the bio vector array phys_segments - number of segments
50 in this bio after physical address coalescing is performed.
51
52 bytes_done
53 number of bytes transferred
54
55 devname
56 device for which a buffer bounce was needed.
57
58 flags
59 see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1
60 RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds
61 error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data
62 BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user
63 pages BIO_EOPNOTSUPP 7 not supported
64
66 The process creating a block IO request.
67
69 tapset::ioblock(3stap)
70
71
72
73SystemTap Tapset Reference November 2021 PROBE::IOBLOCK_TRACE(3stap)