1PROBE::IOBLOCK_TRACE(3staIpO)Scheduler and block IO TaPpRsOBE::IOBLOCK_TRACE(3stap)
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NAME

6       probe::ioblock_trace.request - Fires just as a generic block I/O
7       request is created for a bio.
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SYNOPSIS

10       ioblock_trace.request
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VALUES

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

66       The process makes block I/O request
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SEE ALSO

69       tapset::ioblock(3stap)
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73SystemTap Tapset Reference       November 2021     PROBE::IOBLOCK_TRACE(3stap)
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