Initialize mmp_last_write when the mmp thread starts

A great deal of time may go by between when mmp_init() is called and
the MMP thread starts, particularly if there are bad devices, because
there is I/O checking configs etc.  If this time is too long,

    (gethrtime() - mmp_last_write) > mmp_fail_ns

at the time the MMP thread starts.  If MMP is configured to suspend
the pool, the pool will be suspended immediately.

This can be seen in issue #10838

The value of mmp_last_write doesn't matter before the mmp thread
starts.  To give the MMP thread time to issue and land MMP writes,
initialize mmp_last_write when the MMP thread starts.

Reviewed-by: Giuseppe Di Natale <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Olaf Faaland <[email protected]>
Closes #10873 

0 files changed, 0 insertions, 0 deletions