LU-15283 quota: deadlock between reint & lquota_wb

[fs/lustre-release.git] / lustre / quota / qsd_reint.c

diff --git a/lustre/quota/qsd_reint.c b/lustre/quota/qsd_reint.c
index ac9b86c..666df96 100644 (file)
--- a/lustre/quota/qsd_reint.c
+++ b/lustre/quota/qsd_reint.c
@@ -575,13 +575,13 @@ static int qsd_entry_iter_cb(struct cfs_hash *hs, struct cfs_hash_bd *bd,
        return 0;
 }
 
-static bool qsd_pending_updates(struct qsd_qtype_info *qqi)
+static bool qqi_reint_delayed(struct qsd_qtype_info *qqi)
 {
        struct qsd_instance     *qsd = qqi->qqi_qsd;
        struct qsd_upd_rec      *upd;
        struct lquota_entry     *lqe, *n;
        int                      dqacq = 0;
-       bool                     updates = false;
+       bool                     delay = false;
        ENTRY;
 
        /* any pending quota adjust? */
@@ -594,35 +594,46 @@ static bool qsd_pending_updates(struct qsd_qtype_info *qqi)
        }
        spin_unlock(&qsd->qsd_adjust_lock);
 
+       /* any pending quota request? */
+       cfs_hash_for_each_safe(qqi->qqi_site->lqs_hash, qsd_entry_iter_cb,
+                              &dqacq);
+       if (dqacq) {
+               CDEBUG(D_QUOTA, "%s: pending dqacq for type:%d.\n",
+                      qsd->qsd_svname, qqi->qqi_qtype);
+               GOTO(out, delay = true);
+       }
+
        /* any pending updates? */
-       read_lock(&qsd->qsd_lock);
+       write_lock(&qsd->qsd_lock);
+
+       /* check if the reintegration has already started or finished */
+       if ((qqi->qqi_glb_uptodate && qqi->qqi_slv_uptodate) ||
+            qqi->qqi_reint || qsd->qsd_stopping || qsd->qsd_updating)
+               GOTO(out_lock, delay = true);
+
+       /* there could be some unfinished global or index entry updates
+        * (very unlikely), to avoid them messing up with the reint
+        * procedure, we just return and try to re-start reint later. */
        list_for_each_entry(upd, &qsd->qsd_upd_list, qur_link) {
                if (upd->qur_qqi == qqi) {
-                       read_unlock(&qsd->qsd_lock);
                        CDEBUG(D_QUOTA, "%s: pending %s updates for type:%d.\n",
                               qsd->qsd_svname,
                               upd->qur_global ? "global" : "slave",
                               qqi->qqi_qtype);
-                       GOTO(out, updates = true);
+                       GOTO(out_lock, delay = true);
                }
        }
-       read_unlock(&qsd->qsd_lock);
+       qqi->qqi_reint = 1;
 
-       /* any pending quota request? */
-       cfs_hash_for_each_safe(qqi->qqi_site->lqs_hash, qsd_entry_iter_cb,
-                              &dqacq);
-       if (dqacq) {
-               CDEBUG(D_QUOTA, "%s: pending dqacq for type:%d.\n",
-                      qsd->qsd_svname, qqi->qqi_qtype);
-               updates = true;
-       }
        EXIT;
+out_lock:
+       write_unlock(&qsd->qsd_lock);
 out:
-       if (updates)
+       if (delay)
                CERROR("%s: Delaying reintegration for qtype:%d until pending "
                       "updates are flushed.\n",
                       qsd->qsd_svname, qqi->qqi_qtype);
-       return updates;
+       return delay;
 }
 
 int qsd_start_reint_thread(struct qsd_qtype_info *qqi)
@@ -649,28 +660,8 @@ int qsd_start_reint_thread(struct qsd_qtype_info *qqi)
                /* no space accounting support, can't enable enforcement */
                RETURN(0);
 
-       /* check if the reintegration has already started or finished */
-       write_lock(&qsd->qsd_lock);
-
-       if ((qqi->qqi_glb_uptodate && qqi->qqi_slv_uptodate) ||
-            qqi->qqi_reint || qsd->qsd_stopping) {
-               write_unlock(&qsd->qsd_lock);
+       if (qqi_reint_delayed(qqi))
                RETURN(0);
-       }
-       qqi->qqi_reint = 1;
-
-       write_unlock(&qsd->qsd_lock);
-
-       /* there could be some unfinished global or index entry updates
-        * (very unlikely), to avoid them messing up with the reint
-        * procedure, we just return and try to re-start reint later. */
-       if (qsd_pending_updates(qqi)) {
-               write_lock(&qsd->qsd_lock);
-               qqi->qqi_reint = 0;
-               write_unlock(&qsd->qsd_lock);
-               RETURN(0);
-       }
-
 
        OBD_ALLOC_PTR(args);
        if (args == NULL)