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 opf
14 operations and flags
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16 q
17 request queue on which this bio was queued.
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19 size
20 total size in bytes
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22 bdev_contains
23 points to the device object which contains the partition (when bio
24 structure represents a partition)
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26 ino
27 i-node number of the mapped file
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29 bdev
30 target block device
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32 vcnt
33 bio vector count which represents number of array element (page,
34 offset, length) which makes up this I/O request
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36 sector
37 beginning sector for the entire bio
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39 p_start_sect
40 points to the start sector of the partition structure of the device
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42 rw
43 binary trace for read/write request
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45 flags
46 see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1
47 RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds
48 error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data
49 BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user
50 pages BIO_EOPNOTSUPP 7 not supported
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52 idx
53 offset into the bio vector array phys_segments - number of segments
54 in this bio after physical address coalescing is performed.
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56 devname
57 device for which a buffer bounce was needed.
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59 bytes_done
60 number of bytes transferred
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62 name
63 name of the probe point
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66 The process creating a block IO request.
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69 tapset::ioblock(3stap)
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73SystemTap Tapset Reference November 2022 PROBE::IOBLOCK_TRACE(3stap)