mirror of
https://github.com/ibm-s390-linux/s390-tools.git
synced 2026-08-05 02:14:52 +00:00
d8c630e5f4
Function get_payload_records() reading from disk, blindly adds payload
record (junks) to a list in a 2-stage hierarchical hash keyed with
request ID and PAY area.
On adapter offline/online, zfcp resets the request ID to re-start with 1.
Hence it's not a unique foreign key in the lifetime of the PAY area.
The last payload record (junks) read for the same request ID and PAY area
is the one printed as named PAY field in the tool output.
This is not necessarily the chronologically last record due to PAY area
wrapping.
With this workaround, we:
* warn on reading PAY records if ambiguous entries occurred,
* print additional PAY timestamps which the user can compare
with the actual trace record timestamps to determine if they are close
enough to indicate a match.
We only found this by accident because we kept "short" "payload" being a
built-in part of some actual trace record types in areas HBA, SAN, SCSI.
For above cases, the full PAYload did not match the
built-in "short" "payload".
While at it, also add a comment that PAY output can also be wrong
in another case when junks of multi-part PAY records are missing due
to PAY area wrapping.
Below is an abbreviated example output with this workaround:
Loading trace records ...(this might take a while)
Warning: Ambiguous PAYload records. reqid:0000000000000037 area:san_res
...
Timestamp : 2017-07-07-18:01:34:574827
Area : SAN
...
Tag : fssct_1
Request ID : 0x0000000000000037
Destination ID : 0x00fffffc
SAN req short : 01000000 fc020000 01720ffc 00000000
00000008
SAN req length : 20
Timestamp : 2017-07-07-18:01:34:619310 ------------------+
Area : SAN |
... |
Tag : fsscth2 |
Request ID : 0x0000000000000037 |
Destination ID : 0x00fffffc |
SAN resp short : 01000000 fc020000 80020000 00000000 |
00671a07 00000000 c05076ff d6801850 |
00671a7e 00000000 c05076ff d6801968 |
SAN resp length: 16384 |
Payload time : 2017-07-07-18:16:17:165708 <== does not match
San resp info : 01000000 fc020000 80020000 00000000 <== wrong
4a49424d 20202020 20323936 34202020 <== wrong
20202020 20202020 20303230 30303030 <== wrong
30303745 43383720 20504348 49443a20 <== wrong
30313938 204e5049 5620556c 7049643a <== wrong
20303536 30303330 30202020 00000000 <== wrong
00000000 00000000 00000000 00000000 <== wrong
... <== wrong
...
Timestamp : 2017-07-07-18:16:17:165713
Area : SAN
...
Tag : fsscth2
Request ID : 0x0000000000000037 <== same reqid & pay "area"
Destination ID : 0x00fffffc
SAN resp short : 01000000 fc020000 80020000 00000000
4a49424d 20202020 20323936 34202020
20202020 20202020 20303230 30303030
SAN resp length: 273
Payload time : 2017-07-07-18:16:17:165708 <== 2nd & last, match
close to Timestamp
San resp info : 01000000 fc020000 80020000 00000000
4a49424d 20202020 20323936 34202020
20202020 20202020 20303230 30303030
30303745 43383720 20504348 49443a20
30313938 204e5049 5620556c 7049643a
20303536 30303330 30202020 00000000
00000000 00000000 00000000 00000000
...
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>