1PROBE::IOBLOCK_TRACE(3staIpO)Scheduler and block IO TaPpRsOBE::IOBLOCK_TRACE(3stap)
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6 probe::ioblock_trace.bounce - Fires whenever a buffer bounce is needed
7 for at least one page of a block IO request.
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10 ioblock_trace.bounce
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13 flags
14 see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1
15 RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds
16 error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn´t own data
17 BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user
18 pages BIO_EOPNOTSUPP 7 not supported
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20 devname
21 device for which a buffer bounce was needed.
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23 bdev
24 target block device
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26 sector
27 beginning sector for the entire bio
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29 name
30 name of the probe point
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32 size
33 total size in bytes
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35 p_start_sect
36 points to the start sector of the partition structure of the device
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38 vcnt
39 bio vector count which represents number of array element (page,
40 offset, length) which makes up this I/O request
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42 bytes_done
43 number of bytes transferred
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45 q
46 request queue on which this bio was queued.
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48 idx
49 offset into the bio vector array phys_segments - number of segments
50 in this bio after physical address coalescing is performed.
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52 ino
53 i-node number of the mapped file
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55 bdev_contains
56 points to the device object which contains the partition (when bio
57 structure represents a partition)
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59 rw
60 binary trace for read/write request
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63 The process creating a block IO request.
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66 tapset::ioblock(3stap)
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70SystemTap Tapset Reference June 2018 PROBE::IOBLOCK_TRACE(3stap)