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

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

10       ioblock.request
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VALUES

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

67       The process makes block I/O request
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SEE ALSO

70       tapset::ioblock(3stap)
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74SystemTap Tapset Reference       November 2022       PROBE::IOBLOCK.REQ(3stap)
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