Report duration and error in mmp_history entries
After an MMP write completes, update the relevant mmp_history entry
with the time between submission and completion, and the error
status of the write.
[faaland1@toss3a zfs]$ cat /proc/spl/kstat/zfs/pool/multihost
39 0 0x01 100 8800
69147946270893 72723903122926
id txg timestamp error duration mmp_delay vdev_guid
10607 1166
1518985089 0 138301
637785455 4882...
10608 1166
1518985089 0 136154
635407747 1151...
10609 1166
1518985089 0
803618560 633048078 9740...
10610 1166
1518985090 0 144826
633048078 4882...
10611 1166
1518985090 0 164527
666187671 1151...
Where duration = gethrtime_in_done_fn - gethrtime_at_submission, and
error = zio->io_error.
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes #7190