Make txg_wait_synced conditional in zfsvfs_teardown

The call to txg_wait_synced in zfsvfs_teardown should
be made conditional on the objset having dirty data.
This can prevent unnecessary txg_wait_synced during
some unmount operations.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Zuchowski <pzuchowski@datto.com>
Closes #9115
This commit is contained in:
Paul Zuchowski 2019-08-15 10:27:13 -04:00 committed by Tony Hutter
parent 93fd9101c9
commit 9d4ca81b6f

View File

@ -1785,8 +1785,17 @@ zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting)
* Evict cached data. We must write out any dirty data before
* disowning the dataset.
*/
if (!zfs_is_readonly(zfsvfs))
objset_t *os = zfsvfs->z_os;
boolean_t os_dirty = B_FALSE;
for (int t = 0; t < TXG_SIZE; t++) {
if (dmu_objset_is_dirty(os, t)) {
os_dirty = B_TRUE;
break;
}
}
if (!zfs_is_readonly(zfsvfs) && os_dirty) {
txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0);
}
dmu_objset_evict_dbufs(zfsvfs->z_os);
return (0);