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 None
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16 name - name of the probe point q - request queue on which this bio was
17 queued. devname - device for which a buffer bounce was needed. ino -
18 i-node number of the mapped file bytes_done - number of bytes
19 transferred sector - beginning sector for the entire bio flags - see
20 below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1 RW_AHEAD
21 set, and read/write would block BIO_EOF 2 out-out-bounds error
22 BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data
23 BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user pages
24 BIO_EOPNOTSUPP 7 not supported rw - binary trace for read/write request
25 vcnt - bio vector count which represents number of array element (page,
26 offset, length) which makes up this I/O request idx - offset into the
27 bio vector array phys_segments - number of segments in this bio after
28 physical address coalescing is performed. size - total size in bytes
29 bdev - target block device bdev_contains - points to the device object
30 which contains the partition (when bio structure represents a
31 partition) p_start_sect - points to the start sector of the partition
32 structure of the device
33
35 The process creating a block IO request.
36SystemTap Tapset Reference August 2011 PROBE::IOBLOCK_TRACE(3stap)