zfs/cmd/ztest
Olaf Faaland 0582e40322 Add callback for zfs_multihost_interval
Add a callback to wake all running mmp threads when
zfs_multihost_interval is changed.

This is necessary when the interval is changed from a very large value
to a significantly lower one, while pools are imported that have the
multihost property enabled.

Without this commit, the mmp thread does not wake up and detect the new
interval until after it has waited the old multihost interval time.  A
user monitoring mmp writes via the provided kstat would be led to
believe that the changed setting did not work.

Added a test in the ZTS under mmp to verify the new functionality is
working.

Added a test to ztest which starts and stops mmp threads, and calls into
the code to signal sleeping mmp threads, to test for deadlocks or
similar locking issues.

Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes #6387
2017-07-25 13:22:20 -04:00
..
.gitignore Add .gitignore files to exclude build products 2010-01-08 11:35:17 -08:00
Makefile.am GCC 7.1 fixes 2017-06-28 10:05:16 -07:00
ztest.c Add callback for zfs_multihost_interval 2017-07-25 13:22:20 -04:00