xfs: fix dquot isolation hang

The new LRU list isolation code in xfs_qm_dquot_isolate() isn't
completely up to date.  Firstly, it needs conversion to return enum
lru_status values, not raw numbers. Secondly - most importantly - it
fails to unlock the dquot and relock the LRU in the LRU_RETRY path.
This leads to deadlocks in xfstests generic/232. Fix them.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Cc: Glauber Costa <glommer@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Dave Chinner 2013-08-28 10:18:08 +10:00 committed by Al Viro
parent 2f5b56f856
commit 35163417fb

View file

@ -707,7 +707,7 @@ xfs_qm_dquot_isolate(
trace_xfs_dqreclaim_want(dqp);
list_del_init(&dqp->q_lru);
XFS_STATS_DEC(xs_qm_dquot_unused);
return 0;
return LRU_REMOVED;
}
/*
@ -753,17 +753,19 @@ xfs_qm_dquot_isolate(
XFS_STATS_DEC(xs_qm_dquot_unused);
trace_xfs_dqreclaim_done(dqp);
XFS_STATS_INC(xs_qm_dqreclaims);
return 0;
return LRU_REMOVED;
out_miss_busy:
trace_xfs_dqreclaim_busy(dqp);
XFS_STATS_INC(xs_qm_dqreclaim_misses);
return 2;
return LRU_SKIP;
out_unlock_dirty:
trace_xfs_dqreclaim_busy(dqp);
XFS_STATS_INC(xs_qm_dqreclaim_misses);
return 3;
xfs_dqunlock(dqp);
spin_lock(lru_lock);
return LRU_RETRY;
}
static unsigned long