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       bdev
14           target block device
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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       size
20           total size in bytes
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22       devname
23           block device name
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25       opf
26           operations and flags
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28       q
29           request queue on which this bio was queued.
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31       idx
32           offset into the bio vector array phys_segments - number of segments
33           in this bio after physical address coalescing is performed.
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35       rw
36           binary trace for read/write request
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38       bytes_done
39           number of bytes transferred
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41       flags
42           see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1
43           RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds
44           error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data
45           BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user
46           pages BIO_EOPNOTSUPP 7 not supported
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48       name
49           name of the probe point
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51       bdev_contains
52           points to the device object which contains the partition (when bio
53           structure represents a partition)
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55       sector
56           beginning sector for the entire bio
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58       vcnt
59           bio vector count which represents number of array element (page,
60           offset, length) which make up this I/O request
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62       ino
63           i-node number of the mapped file
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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       October 2018      PROBE::IOBLOCK_TRACE(3stap)
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