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