[patch 09/19] xfs: cleanup xfs_qm_dqlookup

Christoph Hellwig
2011-12-06T21:58:55Z

[-- Attachment #1: xfs-cleanup-xfs_qm_dqlookup --]
[-- Type: text/plain, Size: 1877 bytes --]

Rearrange the code to avoid the conditional locking around the flist_locked
variable. This means we lose a (rather pointless) assert, and hold the
freelist lock a bit longer for one corner case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

---
fs/xfs/xfs_dquot.c | 25 +++++--------------------
1 file changed, 5 insertions(+), 20 deletions(-)

Index: xfs/fs/xfs/xfs_dquot.c
===================================================================
--- xfs.orig/fs/xfs/xfs_dquot.c 2011-10-27 22:40:02.250173174 +0200
+++ xfs/fs/xfs/xfs_dquot.c 2011-10-27 22:40:02.770171231 +0200
@@ -710,12 +710,9 @@ xfs_qm_dqlookup(
xfs_dquot_t **O_dqpp)
{
xfs_dquot_t *dqp;
- uint flist_locked;

ASSERT(mutex_is_locked(&qh->qh_lock));

- flist_locked = B_FALSE;
-
/*
* Traverse the hashchain looking for a match
*/
@@ -750,31 +747,19 @@ xfs_qm_dqlookup(
xfs_dqlock(dqp);
dqp->dq_flags &= ~(XFS_DQ_WANT);
}
- flist_locked = B_TRUE;
- }
-
- /*
- * id couldn't have changed; we had the hashlock all
- * along
- */
- ASSERT(be32_to_cpu(dqp->q_core.d_id) == id);

- if (flist_locked) {
- if (dqp->q_nrefs != 0) {
- mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
- flist_locked = B_FALSE;
- } else {
+ if (dqp->q_nrefs == 0) {
/* take it off the freelist */
trace_xfs_dqlookup_freelist(dqp);
list_del_init(&dqp->q_freelist);
xfs_Gqm->qm_dqfrlist_cnt--;
}
+ XFS_DQHOLD(dqp);
+ mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
+ } else {
+ XFS_DQHOLD(dqp);
}

- XFS_DQHOLD(dqp);
-
- if (flist_locked)
- mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
/*
* move the dquot to the front of the hashchain
*/