LU-11518 ldlm: pool recalc forceful call

[fs/lustre-release.git] / lustre / ldlm / ldlm_request.c

diff --git a/lustre/ldlm/ldlm_request.c b/lustre/ldlm/ldlm_request.c
index c322f15..b53a858 100644 (file)
--- a/lustre/ldlm/ldlm_request.c
+++ b/lustre/ldlm/ldlm_request.c
@@ -1418,8 +1418,9 @@ static inline struct ldlm_pool *ldlm_imp2pl(struct obd_import *imp)
  */
 int ldlm_cli_update_pool(struct ptlrpc_request *req)
 {
+       struct ldlm_namespace *ns;
        struct obd_device *obd;
-       __u64 new_slv;
+       __u64 new_slv, ratio;
        __u32 new_limit;
 
        ENTRY;
@@ -1457,17 +1458,39 @@ int ldlm_cli_update_pool(struct ptlrpc_request *req)
        read_unlock(&obd->obd_pool_lock);
 
        /*
-        * Set new SLV and limit in OBD fields to make them accessible
-        * to the pool thread. We do not access obd_namespace and pool
-        * directly here as there is no reliable way to make sure that
-        * they are still alive at cleanup time. Evil races are possible
-        * which may cause Oops at that time.
+        * OBD device keeps the new pool attributes before they are handled by
+        * the pool.
         */
        write_lock(&obd->obd_pool_lock);
        obd->obd_pool_slv = new_slv;
        obd->obd_pool_limit = new_limit;
        write_unlock(&obd->obd_pool_lock);
 
+       /*
+        * Check if an urgent pool recalc is needed, let it to be a change of
+        * SLV on 10%. It is applicable to LRU resize enabled case only.
+        */
+       ns = obd->obd_namespace;
+       if (!ns_connect_lru_resize(ns) ||
+           ldlm_pool_get_slv(&ns->ns_pool) < new_slv)
+               RETURN(0);
+
+       ratio = 100 * new_slv / ldlm_pool_get_slv(&ns->ns_pool);
+       if (100 - ratio >= ns->ns_recalc_pct &&
+           !ns->ns_stopping && !ns->ns_rpc_recalc) {
+               bool recalc = false;
+
+               spin_lock(&ns->ns_lock);
+               if (!ns->ns_stopping && !ns->ns_rpc_recalc) {
+                       ldlm_namespace_get(ns);
+                       recalc = true;
+                       ns->ns_rpc_recalc = 1;
+               }
+               spin_unlock(&ns->ns_lock);
+               if (recalc)
+                       ldlm_bl_to_thread_ns(ns);
+       }
+
        RETURN(0);
 }