[patch 10/19] xfs: remove XFS_DQ_INACTIVE

Christoph Hellwig
2011-12-06T21:58:56Z

[-- Attachment #1: xfs-kill-XFS_DQ_INACTIVE --]
[-- Type: text/plain, Size: 5834 bytes --]

Free dquots when purging them during umount instead of keeping them around
on the freelist in a degraded state. The out of order locking in
xfs_qm_dqpurge will be removed again later in this series.

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

---
fs/xfs/xfs_dquot.c | 28 ++++++++++++++----------
fs/xfs/xfs_qm.c | 61 +++++------------------------------------------------
fs/xfs/xfs_quota.h | 4 ---
3 files changed, 24 insertions(+), 69 deletions(-)

Index: xfs/fs/xfs/xfs_dquot.c
===================================================================
--- xfs.orig/fs/xfs/xfs_dquot.c 2011-12-06 15:39:14.567014922 +0100
+++ xfs/fs/xfs/xfs_dquot.c 2011-12-06 15:40:48.533683330 +0100
@@ -1302,6 +1302,14 @@ xfs_qm_dqpurge(
ASSERT(mutex_is_locked(&mp->m_quotainfo->qi_dqlist_lock));
ASSERT(mutex_is_locked(&dqp->q_hash->qh_lock));

+ /*
+ * XXX(hch): horrible locking order, will get cleaned up ASAP.
+ */
+ if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
+ mutex_unlock(&dqp->q_hash->qh_lock);
+ return 1;
+ }
+
xfs_dqlock(dqp);
/*
* We really can't afford to purge a dquot that is
@@ -1364,25 +1372,23 @@ xfs_qm_dqpurge(

list_del_init(&dqp->q_hashlist);
qh->qh_version++;
+
list_del_init(&dqp->q_mplist);
mp->m_quotainfo->qi_dqreclaims++;
mp->m_quotainfo->qi_dquots--;
- /*
- * XXX Move this to the front of the freelist, if we can get the
- * freelist lock.
- */
- ASSERT(!list_empty(&dqp->q_freelist));

- dqp->q_mount = NULL;
- dqp->q_hash = NULL;
- dqp->dq_flags = XFS_DQ_INACTIVE;
- memset(&dqp->q_core, 0, sizeof(dqp->q_core));
+ list_del_init(&dqp->q_freelist);
+ xfs_Gqm->qm_dqfrlist_cnt--;
+
xfs_dqfunlock(dqp);
xfs_dqunlock(dqp);
+
+ mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
mutex_unlock(&qh->qh_lock);
- return (0);
-}

+ xfs_qm_dqdestroy(dqp);
+ return 0;
+}

/*
* Give the buffer a little push if it is incore and
Index: xfs/fs/xfs/xfs_qm.c
===================================================================
--- xfs.orig/fs/xfs/xfs_qm.c 2011-12-06 15:38:33.840347499 +0100
+++ xfs/fs/xfs/xfs_qm.c 2011-12-06 15:40:10.733682629 +0100
@@ -154,12 +154,17 @@ STATIC void
xfs_qm_destroy(
struct xfs_qm *xqm)
{
- struct xfs_dquot *dqp, *n;
int hsize, i;

ASSERT(xqm != NULL);
ASSERT(xqm->qm_nrefs == 0);
+
unregister_shrinker(&xfs_qm_shaker);
+
+ mutex_lock(&xqm->qm_dqfrlist_lock);
+ ASSERT(list_empty(&xqm->qm_dqfrlist));
+ mutex_unlock(&xqm->qm_dqfrlist_lock);
+
hsize = xqm->qm_dqhashmask + 1;
for (i = 0; i < hsize; i++) {
xfs_qm_list_destroy(&(xqm->qm_usr_dqhtable[i]));
@@ -171,17 +176,6 @@ xfs_qm_destroy(
xqm->qm_grp_dqhtable = NULL;
xqm->qm_dqhashmask = 0;

- /* frlist cleanup */
- mutex_lock(&xqm->qm_dqfrlist_lock);
- list_for_each_entry_safe(dqp, n, &xqm->qm_dqfrlist, q_freelist) {
- xfs_dqlock(dqp);
- list_del_init(&dqp->q_freelist);
- xfs_Gqm->qm_dqfrlist_cnt--;
- xfs_dqunlock(dqp);
- xfs_qm_dqdestroy(dqp);
- }
- mutex_unlock(&xqm->qm_dqfrlist_lock);
- mutex_destroy(&xqm->qm_dqfrlist_lock);
kmem_free(xqm);
}

@@ -232,34 +226,10 @@ STATIC void
xfs_qm_rele_quotafs_ref(
struct xfs_mount *mp)
{
- xfs_dquot_t *dqp, *n;
-
ASSERT(xfs_Gqm);
ASSERT(xfs_Gqm->qm_nrefs > 0);

/*
- * Go thru the freelist and destroy all inactive dquots.
- */
- mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
-
- list_for_each_entry_safe(dqp, n, &xfs_Gqm->qm_dqfrlist, q_freelist) {
- xfs_dqlock(dqp);
- if (dqp->dq_flags & XFS_DQ_INACTIVE) {
- ASSERT(dqp->q_mount == NULL);
- ASSERT(! XFS_DQ_IS_DIRTY(dqp));
- ASSERT(list_empty(&dqp->q_hashlist));
- ASSERT(list_empty(&dqp->q_mplist));
- list_del_init(&dqp->q_freelist);
- xfs_Gqm->qm_dqfrlist_cnt--;
- xfs_dqunlock(dqp);
- xfs_qm_dqdestroy(dqp);
- } else {
- xfs_dqunlock(dqp);
- }
- }
- mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
-
- /*
* Destroy the entire XQM. If somebody mounts with quotaon, this'll
* be restarted.
*/
@@ -1728,8 +1698,6 @@ again:
* both the dquot and the freelistlock.
*/
if (dqp->dq_flags & XFS_DQ_WANT) {
- ASSERT(! (dqp->dq_flags & XFS_DQ_INACTIVE));
-
trace_xfs_dqreclaim_want(dqp);
XQM_STATS_INC(xqmstats.xs_qm_dqwants);
restarts++;
@@ -1737,23 +1705,6 @@ again:
goto dqunlock;
}

- /*
- * If the dquot is inactive, we are assured that it is
- * not on the mplist or the hashlist, and that makes our
- * life easier.
- */
- if (dqp->dq_flags & XFS_DQ_INACTIVE) {
- ASSERT(mp == NULL);
- ASSERT(! XFS_DQ_IS_DIRTY(dqp));
- ASSERT(list_empty(&dqp->q_hashlist));
- ASSERT(list_empty(&dqp->q_mplist));
- list_del_init(&dqp->q_freelist);
- xfs_Gqm->qm_dqfrlist_cnt--;
- dqpout = dqp;
- XQM_STATS_INC(xqmstats.xs_qm_dqinact_reclaims);
- goto dqunlock;
- }
-
ASSERT(dqp->q_hash);
ASSERT(!list_empty(&dqp->q_mplist));

Index: xfs/fs/xfs/xfs_quota.h
===================================================================
--- xfs.orig/fs/xfs/xfs_quota.h 2011-12-06 15:37:21.710346162 +0100
+++ xfs/fs/xfs/xfs_quota.h 2011-12-06 15:40:10.733682629 +0100
@@ -88,7 +88,6 @@ typedef struct xfs_dqblk {
#define XFS_DQ_GROUP 0x0004 /* a group quota */
#define XFS_DQ_DIRTY 0x0008 /* dquot is dirty */
#define XFS_DQ_WANT 0x0010 /* for lookup/reclaim race */
-#define XFS_DQ_INACTIVE 0x0020 /* dq off mplist & hashlist */

#define XFS_DQ_ALLTYPES (XFS_DQ_USER|XFS_DQ_PROJ|XFS_DQ_GROUP)

@@ -97,8 +96,7 @@ typedef struct xfs_dqblk {
{ XFS_DQ_PROJ, "PROJ" }, \
{ XFS_DQ_GROUP, "GROUP" }, \
{ XFS_DQ_DIRTY, "DIRTY" }, \
- { XFS_DQ_WANT, "WANT" }, \
- { XFS_DQ_INACTIVE, "INACTIVE" }
+ { XFS_DQ_WANT, "WANT" }

/*
* In the worst case, when both user and group quotas are on,