LU-8900 snapshot: new config for MDT write barrier

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

diff --git a/lustre/ldlm/ldlm_inodebits.c b/lustre/ldlm/ldlm_inodebits.c
index 0c31481..636527b 100644 (file)
--- a/lustre/ldlm/ldlm_inodebits.c
+++ b/lustre/ldlm/ldlm_inodebits.c
@@ -15,11 +15,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
@@ -27,7 +23,7 @@
  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2011, 2013, Intel Corporation.
+ * Copyright (c) 2011, 2016, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -56,6 +52,7 @@
 #include <lustre_dlm.h>
 #include <obd_support.h>
 #include <lustre_lib.h>
+#include <obd_class.h>
 
 #include "ldlm_internal.h"
 
@@ -81,7 +78,6 @@ ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req,
 {
        struct list_head *tmp;
        struct ldlm_lock *lock;
-       enum ldlm_mode req_mode = req->l_req_mode;
        __u64 req_bits = req->l_policy_data.l_inodebits.bits;
        int compat = 1;
        ENTRY;
@@ -98,23 +94,33 @@ ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req,
                /* We stop walking the queue if we hit ourselves so we don't
                 * take conflicting locks enqueued after us into account,
                 * or we'd wait forever. */
-                if (req == lock)
-                        RETURN(compat);
+               if (req == lock)
+                       RETURN(compat);
 
-                /* last lock in mode group */
-                LASSERT(lock->l_sl_mode.prev != NULL);
+               /* last lock in mode group */
+               LASSERT(lock->l_sl_mode.prev != NULL);
                mode_tail = &list_entry(lock->l_sl_mode.prev,
-                                            struct ldlm_lock,
-                                            l_sl_mode)->l_res_link;
+                                       struct ldlm_lock,
+                                       l_sl_mode)->l_res_link;
+
+               /* if reqest lock is not COS_INCOMPAT and COS is disabled,
+                * they are compatible, IOW this request is from a local
+                * transaction on a DNE system. */
+               if (lock->l_req_mode == LCK_COS && !ldlm_is_cos_incompat(req) &&
+                   !ldlm_is_cos_enabled(req)) {
+                       /* jump to last lock in mode group */
+                       tmp = mode_tail;
+                       continue;
+               }
 
-                /* locks are compatible, bits don't matter */
-                if (lockmode_compat(lock->l_req_mode, req_mode)) {
-                        /* jump to last lock in mode group */
-                        tmp = mode_tail;
-                        continue;
-                }
+               /* locks' mode are compatible, bits don't matter */
+               if (lockmode_compat(lock->l_req_mode, req->l_req_mode)) {
+                       /* jump to last lock in mode group */
+                       tmp = mode_tail;
+                       continue;
+               }
 
-                for (;;) {
+               for (;;) {
                        struct list_head *head;
 
                        /* Advance loop cursor to last lock in policy group. */
@@ -128,6 +134,8 @@ ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req,
                                 * requirement: it is only compatible with
                                 * locks from the same client. */
                                if (lock->l_req_mode == LCK_COS &&
+                                   !ldlm_is_cos_incompat(req) &&
+                                   ldlm_is_cos_enabled(req) &&
                                    lock->l_client_cookie == req->l_client_cookie)
                                        goto not_conflicting;
                                /* Found a conflicting policy group. */
@@ -206,8 +214,8 @@ int ldlm_process_inodebits_lock(struct ldlm_lock *lock, __u64 *flags,
                 ldlm_grant_lock(lock, work_list);
 
                *err = ELDLM_OK;
-                RETURN(LDLM_ITER_CONTINUE);
-        }
+               RETURN(LDLM_ITER_CONTINUE);
+       }
 
  restart:
         rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, &rpc_list);
@@ -226,21 +234,35 @@ int ldlm_process_inodebits_lock(struct ldlm_lock *lock, __u64 *flags,
                 rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list,
                                        LDLM_WORK_BL_AST);
                 lock_res(res);
-               if (rc == -ERESTART)
+               if (rc == -ERESTART) {
+                       /* We were granted while waiting, nothing left to do */
+                       if (lock->l_granted_mode == lock->l_req_mode)
+                               GOTO(out, rc = 0);
+                       /* Lock was destroyed while we were waiting, abort */
+                       if (ldlm_is_destroyed(lock))
+                               GOTO(out, rc = -EAGAIN);
+
+                       /* Otherwise try again */
                        GOTO(restart, rc);
+               }
                 *flags |= LDLM_FL_BLOCK_GRANTED;
         } else {
                 ldlm_resource_unlink_lock(lock);
                 ldlm_grant_lock(lock, NULL);
         }
-        RETURN(0);
+
+       rc = 0;
+out:
+       *err = rc;
+       LASSERT(list_empty(&rpc_list));
+
+       RETURN(rc);
 }
 #endif /* HAVE_SERVER_SUPPORT */
 
 void ldlm_ibits_policy_wire_to_local(const union ldlm_wire_policy_data *wpolicy,
                                     union ldlm_policy_data *lpolicy)
 {
-       memset(lpolicy, 0, sizeof(*lpolicy));
        lpolicy->l_inodebits.bits = wpolicy->l_inodebits.bits;
 }