*/
struct mutex xfs_Gqm_lock;
struct xfs_qm *xfs_Gqm;
-uint ndquot;
kmem_zone_t *qm_dqzone;
kmem_zone_t *qm_dqtrxzone;
goto out_free_udqhash;
hsize /= sizeof(xfs_dqhash_t);
- ndquot = hsize << 8;
xqm = kmem_zalloc(sizeof(xfs_qm_t), KM_SLEEP);
xqm->qm_dqhashmask = hsize - 1;
xqm->qm_dqtrxzone = qm_dqtrxzone;
atomic_set(&xqm->qm_totaldquots, 0);
- xqm->qm_dqfree_ratio = XFS_QM_DQFREE_RATIO;
xqm->qm_nrefs = 0;
return xqm;
return 0;
}
+STATIC void
+xfs_qm_dqfree_one(
+ struct xfs_dquot *dqp)
+{
+ struct xfs_mount *mp = dqp->q_mount;
+ struct xfs_quotainfo *qi = mp->m_quotainfo;
+ mutex_lock(&dqp->q_hash->qh_lock);
+ list_del_init(&dqp->q_hashlist);
+ dqp->q_hash->qh_version++;
+ mutex_unlock(&dqp->q_hash->qh_lock);
-/*
- * Pop the least recently used dquot off the freelist and recycle it.
- */
-STATIC struct xfs_dquot *
-xfs_qm_dqreclaim_one(void)
+ mutex_lock(&qi->qi_dqlist_lock);
+ list_del_init(&dqp->q_mplist);
+ qi->qi_dquots--;
+ qi->qi_dqreclaims++;
+ mutex_unlock(&qi->qi_dqlist_lock);
+
+ xfs_qm_dqdestroy(dqp);
+}
+
+STATIC void
+xfs_qm_dqreclaim_one(
+ struct xfs_dquot *dqp,
+ struct list_head *dispose_list)
{
- struct xfs_dquot *dqp;
- int restarts = 0;
+ struct xfs_mount *mp = dqp->q_mount;
+ int error;
- mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
-restart:
- list_for_each_entry(dqp, &xfs_Gqm->qm_dqfrlist, q_freelist) {
- struct xfs_mount *mp = dqp->q_mount;
+ if (!xfs_dqlock_nowait(dqp))
+ goto out_busy;
- if (!xfs_dqlock_nowait(dqp))
- continue;
+ /*
+ * This dquot has acquired a reference in the meantime remove it from
+ * the freelist and try again.
+ */
+ if (dqp->q_nrefs) {
+ xfs_dqunlock(dqp);
- /*
- * This dquot has already been grabbed by dqlookup.
- * Remove it from the freelist and try again.
- */
- if (dqp->q_nrefs) {
- trace_xfs_dqreclaim_want(dqp);
- XQM_STATS_INC(xqmstats.xs_qm_dqwants);
-
- list_del_init(&dqp->q_freelist);
- xfs_Gqm->qm_dqfrlist_cnt--;
- restarts++;
- goto dqunlock;
- }
+ trace_xfs_dqreclaim_want(dqp);
+ XQM_STATS_INC(xqmstats.xs_qm_dqwants);
- ASSERT(dqp->q_hash);
- ASSERT(!list_empty(&dqp->q_mplist));
+ list_del_init(&dqp->q_freelist);
+ xfs_Gqm->qm_dqfrlist_cnt--;
+ return;
+ }
- /*
- * Try to grab the flush lock. If this dquot is in the process
- * of getting flushed to disk, we don't want to reclaim it.
- */
- if (!xfs_dqflock_nowait(dqp))
- goto dqunlock;
+ ASSERT(dqp->q_hash);
+ ASSERT(!list_empty(&dqp->q_mplist));
- /*
- * We have the flush lock so we know that this is not in the
- * process of being flushed. So, if this is dirty, flush it
- * DELWRI so that we don't get a freelist infested with
- * dirty dquots.
- */
- if (XFS_DQ_IS_DIRTY(dqp)) {
- int error;
+ /*
+ * Try to grab the flush lock. If this dquot is in the process of
+ * getting flushed to disk, we don't want to reclaim it.
+ */
+ if (!xfs_dqflock_nowait(dqp))
+ goto out_busy;
- trace_xfs_dqreclaim_dirty(dqp);
+ /*
+ * We have the flush lock so we know that this is not in the
+ * process of being flushed. So, if this is dirty, flush it
+ * DELWRI so that we don't get a freelist infested with
+ * dirty dquots.
+ */
+ if (XFS_DQ_IS_DIRTY(dqp)) {
+ trace_xfs_dqreclaim_dirty(dqp);
- /*
- * We flush it delayed write, so don't bother
- * releasing the freelist lock.
- */
- error = xfs_qm_dqflush(dqp, SYNC_TRYLOCK);
- if (error) {
- xfs_warn(mp, "%s: dquot %p flush failed",
- __func__, dqp);
- }
- goto dqunlock;
+ /*
+ * We flush it delayed write, so don't bother releasing the
+ * freelist lock.
+ */
+ error = xfs_qm_dqflush(dqp, 0);
+ if (error) {
+ xfs_warn(mp, "%s: dquot %p flush failed",
+ __func__, dqp);
}
- xfs_dqfunlock(dqp);
/*
- * Prevent lookup now that we are going to reclaim the dquot.
- * Once XFS_DQ_FREEING is set lookup won't touch the dquot,
- * thus we can drop the lock now.
+ * Give the dquot another try on the freelist, as the
+ * flushing will take some time.
*/
- dqp->dq_flags |= XFS_DQ_FREEING;
- xfs_dqunlock(dqp);
-
- mutex_lock(&dqp->q_hash->qh_lock);
- list_del_init(&dqp->q_hashlist);
- dqp->q_hash->qh_version++;
- mutex_unlock(&dqp->q_hash->qh_lock);
-
- mutex_lock(&mp->m_quotainfo->qi_dqlist_lock);
- list_del_init(&dqp->q_mplist);
- mp->m_quotainfo->qi_dquots--;
- mp->m_quotainfo->qi_dqreclaims++;
- mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock);
+ goto out_busy;
+ }
+ xfs_dqfunlock(dqp);
- ASSERT(dqp->q_nrefs == 0);
- list_del_init(&dqp->q_freelist);
- xfs_Gqm->qm_dqfrlist_cnt--;
+ /*
+ * Prevent lookups now that we are past the point of no return.
+ */
+ dqp->dq_flags |= XFS_DQ_FREEING;
+ xfs_dqunlock(dqp);
- mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
- return dqp;
-dqunlock:
- xfs_dqunlock(dqp);
- if (restarts >= XFS_QM_RECLAIM_MAX_RESTARTS)
- break;
- goto restart;
- }
+ ASSERT(dqp->q_nrefs == 0);
+ list_move_tail(&dqp->q_freelist, dispose_list);
+ xfs_Gqm->qm_dqfrlist_cnt--;
- mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
- return NULL;
-}
+ trace_xfs_dqreclaim_done(dqp);
+ XQM_STATS_INC(xqmstats.xs_qm_dqreclaims);
+ return;
-/*
- * Traverse the freelist of dquots and attempt to reclaim a maximum of
- * 'howmany' dquots. This operation races with dqlookup(), and attempts to
- * favor the lookup function ...
- */
-STATIC int
-xfs_qm_shake_freelist(
- int howmany)
-{
- int nreclaimed = 0;
- xfs_dquot_t *dqp;
+out_busy:
+ xfs_dqunlock(dqp);
- if (howmany <= 0)
- return 0;
+ /*
+ * Move the dquot to the tail of the list so that we don't spin on it.
+ */
+ list_move_tail(&dqp->q_freelist, &xfs_Gqm->qm_dqfrlist);
- while (nreclaimed < howmany) {
- dqp = xfs_qm_dqreclaim_one();
- if (!dqp)
- return nreclaimed;
- xfs_qm_dqdestroy(dqp);
- nreclaimed++;
- }
- return nreclaimed;
+ trace_xfs_dqreclaim_busy(dqp);
+ XQM_STATS_INC(xqmstats.xs_qm_dqreclaim_misses);
}
-/*
- * The kmem_shake interface is invoked when memory is running low.
- */
-/* ARGSUSED */
STATIC int
xfs_qm_shake(
- struct shrinker *shrink,
- struct shrink_control *sc)
+ struct shrinker *shrink,
+ struct shrink_control *sc)
{
- int ndqused, nfree, n;
- gfp_t gfp_mask = sc->gfp_mask;
-
- if (!kmem_shake_allow(gfp_mask))
- return 0;
- if (!xfs_Gqm)
- return 0;
-
- nfree = xfs_Gqm->qm_dqfrlist_cnt; /* free dquots */
- /* incore dquots in all f/s's */
- ndqused = atomic_read(&xfs_Gqm->qm_totaldquots) - nfree;
-
- ASSERT(ndqused >= 0);
+ int nr_to_scan = sc->nr_to_scan;
+ LIST_HEAD (dispose_list);
+ struct xfs_dquot *dqp;
- if (nfree <= ndqused && nfree < ndquot)
+ if ((sc->gfp_mask & (__GFP_FS|__GFP_WAIT)) != (__GFP_FS|__GFP_WAIT))
return 0;
+ if (!nr_to_scan)
+ goto out;
- ndqused *= xfs_Gqm->qm_dqfree_ratio; /* target # of free dquots */
- n = nfree - ndqused - ndquot; /* # over target */
-
- return xfs_qm_shake_freelist(MAX(nfree, n));
-}
-
-
-/*------------------------------------------------------------------*/
-
-/*
- * Return a new incore dquot. Depending on the number of
- * dquots in the system, we either allocate a new one on the kernel heap,
- * or reclaim a free one.
- * Return value is B_TRUE if we allocated a new dquot, B_FALSE if we managed
- * to reclaim an existing one from the freelist.
- */
-boolean_t
-xfs_qm_dqalloc_incore(
- xfs_dquot_t **O_dqpp)
-{
- xfs_dquot_t *dqp;
-
- /*
- * Check against high water mark to see if we want to pop
- * a nincompoop dquot off the freelist.
- */
- if (atomic_read(&xfs_Gqm->qm_totaldquots) >= ndquot) {
- /*
- * Try to recycle a dquot from the freelist.
- */
- if ((dqp = xfs_qm_dqreclaim_one())) {
- XQM_STATS_INC(xqmstats.xs_qm_dqreclaims);
- /*
- * Just zero the core here. The rest will get
- * reinitialized by caller. XXX we shouldn't even
- * do this zero ...
- */
- memset(&dqp->q_core, 0, sizeof(dqp->q_core));
- *O_dqpp = dqp;
- return B_FALSE;
- }
- XQM_STATS_INC(xqmstats.xs_qm_dqreclaim_misses);
+ mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
+ while (!list_empty(&xfs_Gqm->qm_dqfrlist)) {
+ if (nr_to_scan-- <= 0)
+ break;
+ dqp = list_first_entry(&xfs_Gqm->qm_dqfrlist, struct xfs_dquot,
+ q_freelist);
+ xfs_qm_dqreclaim_one(dqp, &dispose_list);
}
+ mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
- /*
- * Allocate a brand new dquot on the kernel heap and return it
- * to the caller to initialize.
- */
- ASSERT(xfs_Gqm->qm_dqzone != NULL);
- *O_dqpp = kmem_zone_zalloc(xfs_Gqm->qm_dqzone, KM_SLEEP);
- atomic_inc(&xfs_Gqm->qm_totaldquots);
-
- return B_TRUE;
+ while (!list_empty(&dispose_list)) {
+ dqp = list_first_entry(&dispose_list, struct xfs_dquot,
+ q_freelist);
+ list_del_init(&dqp->q_freelist);
+ xfs_qm_dqfree_one(dqp);
+ }
+out:
+ return (xfs_Gqm->qm_dqfrlist_cnt / 100) * sysctl_vfs_cache_pressure;
}
-
/*
* Start a transaction and write the incore superblock changes to
* disk. flags parameter indicates which fields have changed.
git.openpandora.org / pandora-kernel.git / blobdiff