Index: linux-2.6.32-358.0.1.el6/fs/quota/dquot.c
===================================================================
--- linux-2.6.32-358.0.1.el6.orig/fs/quota/dquot.c
+++ linux-2.6.32-358.0.1.el6/fs/quota/dquot.c
@@ -1230,7 +1230,7 @@ static int info_bdq_free(struct dquot *d
 int dquot_initialize(struct inode *inode, int type)
 {
 	unsigned int id = 0;
-	int cnt, ret = 0;
+	int cnt, ret = 0, dq_get = 0;
 	struct dquot *got[MAXQUOTAS] = { NULL, NULL };
 	struct super_block *sb = inode->i_sb;
 	qsize_t rsv;
@@ -1240,7 +1240,14 @@ int dquot_initialize(struct inode *inode
 	if (IS_NOQUOTA(inode))
 		return 0;
 
-	/* First get references to structures we might need. */
+	/* In most case, the i_dquot should have been initialized, except
+	 * the newly allocated one. We'd always try to skip the dqget() and
+	 * dqput() calls to avoid unnecessary global lock contention. */
+	if (!(inode->i_state & I_NEW))
+		goto init_idquot;
+
+get_dquots:
+	dq_get = 1;
 	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 		if (type != -1 && cnt != type)
 			continue;
@@ -1254,7 +1261,7 @@ int dquot_initialize(struct inode *inode
 		}
 		got[cnt] = dqget(sb, id, cnt);
 	}
-
+init_idquot:
 	spin_lock(&inode->i_lock);
 	if (IS_NOQUOTA(inode))
 		goto out_err;
@@ -1265,6 +1272,10 @@ int dquot_initialize(struct inode *inode
 		if (!sb_has_quota_active(sb, cnt))
 			continue;
 		if (!inode->i_dquot[cnt]) {
+			if (dq_get == 0) {
+				spin_unlock(&inode->i_lock);
+				goto get_dquots;
+			}
 			inode->i_dquot[cnt] = got[cnt];
 			got[cnt] = NULL;
 			/*
@@ -1272,7 +1283,7 @@ int dquot_initialize(struct inode *inode
 			 * did a write before quota was turned on
 			 */
 			rsv = inode_get_rsv_space(inode);
-			if (unlikely(rsv)) {
+			if (unlikely(rsv) && likely(inode->i_dquot[cnt])) {
 				spin_lock(&dq_data_lock);
 				dquot_resv_space(inode->i_dquot[cnt], rsv);
 				spin_unlock(&dq_data_lock);