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b=18618
[fs/lustre-release.git] / lustre / ldlm / ldlm_request.c
index 6e08c02..1eaa0e1 100644 (file)
@@ -78,11 +78,11 @@ int ldlm_expired_completion_wait(void *data)
                         RETURN(0);
 
                 LDLM_ERROR(lock, "lock timed out (enqueued at "CFS_TIME_T", "
-                          CFS_DURATION_T"s ago); not entering recovery in "
+                           CFS_DURATION_T"s ago); not entering recovery in "
                            "server code, just going back to sleep",
-                          lock->l_enqueued_time.tv_sec,
+                           lock->l_last_activity,
                            cfs_time_sub(cfs_time_current_sec(),
-                           lock->l_enqueued_time.tv_sec));
+                           lock->l_last_activity));
                 if (cfs_time_after(cfs_time_current(), next_dump)) {
                         last_dump = next_dump;
                         next_dump = cfs_time_shift(300);
@@ -99,9 +99,8 @@ int ldlm_expired_completion_wait(void *data)
         ptlrpc_fail_import(imp, lwd->lwd_conn_cnt);
         LDLM_ERROR(lock, "lock timed out (enqueued at "CFS_TIME_T", "
                   CFS_DURATION_T"s ago), entering recovery for %s@%s",
-                  lock->l_enqueued_time.tv_sec,
-                  cfs_time_sub(cfs_time_current_sec(),
-                  lock->l_enqueued_time.tv_sec),
+                  lock->l_last_activity,
+                  cfs_time_sub(cfs_time_current_sec(), lock->l_last_activity),
                   obd2cli_tgt(obd), imp->imp_connection->c_remote_uuid.uuid);
 
         RETURN(0);
@@ -117,23 +116,10 @@ int ldlm_get_enq_timeout(struct ldlm_lock *lock)
         /* Since these are non-updating timeouts, we should be conservative.
            It would be nice to have some kind of "early reply" mechanism for
            lock callbacks too... */
-        timeout = timeout + (timeout >> 1); /* 150% */
+        timeout = min_t(int, at_max, timeout + (timeout >> 1)); /* 150% */
         return max(timeout, ldlm_enqueue_min);
 }
-
-static int is_granted_or_cancelled(struct ldlm_lock *lock)
-{
-        int ret = 0;
-
-        lock_res_and_lock(lock);
-        if (((lock->l_req_mode == lock->l_granted_mode) &&
-             !(lock->l_flags & LDLM_FL_CP_REQD)) ||
-            (lock->l_flags & LDLM_FL_FAILED))
-                ret = 1;
-        unlock_res_and_lock(lock);
-
-        return ret;
-}
+EXPORT_SYMBOL(ldlm_get_enq_timeout);
 
 /**
  * Helper function for ldlm_completion_ast(), updating timings when lock is
@@ -149,7 +135,7 @@ static int ldlm_completion_tail(struct ldlm_lock *lock)
                 result = -EIO;
         } else {
                 delay = cfs_time_sub(cfs_time_current_sec(),
-                                     lock->l_enqueued_time.tv_sec);
+                                     lock->l_last_activity);
                 LDLM_DEBUG(lock, "client-side enqueue: granted after "
                            CFS_DURATION_T"s", delay);
 
@@ -161,8 +147,8 @@ static int ldlm_completion_tail(struct ldlm_lock *lock)
 }
 
 /**
- * Implementation of ->l_completion_ast() for a client that doesn't wait
- * until lock is granted. Suitable for locks enqueued through ptlrpcd or
+ * Implementation of ->l_completion_ast() for a client, that doesn't wait
+ * until lock is granted. Suitable for locks enqueued through ptlrpcd, of
  * other threads that cannot block for long.
  */
 int ldlm_completion_ast_async(struct ldlm_lock *lock, int flags, void *data)
@@ -183,6 +169,7 @@ int ldlm_completion_ast_async(struct ldlm_lock *lock, int flags, void *data)
         LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, "
                    "going forward");
         ldlm_lock_dump(D_OTHER, lock, 0);
+        ldlm_reprocess_all(lock->l_resource);
         RETURN(0);
 }
 
@@ -264,8 +251,16 @@ noreproc:
                 spin_unlock(&imp->imp_lock);
         }
 
-        /* Go to sleep until the lock is granted or cancelled. */
-        rc = l_wait_event(lock->l_waitq, is_granted_or_cancelled(lock), &lwi);
+        if (ns_is_client(lock->l_resource->lr_namespace) &&
+            OBD_FAIL_CHECK_RESET(OBD_FAIL_LDLM_INTR_CP_AST,
+                                 OBD_FAIL_LDLM_CP_BL_RACE | OBD_FAIL_ONCE)) {
+                lock->l_flags |= LDLM_FL_FAIL_LOC;
+                rc = -EINTR;
+        } else {
+                /* Go to sleep until the lock is granted or cancelled. */
+                rc = l_wait_event(lock->l_waitq,
+                                  is_granted_or_cancelled(lock), &lwi);
+        }
 
         if (rc) {
                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
@@ -276,31 +271,22 @@ noreproc:
         RETURN(ldlm_completion_tail(lock));
 }
 
-/*
- * ->l_blocking_ast() callback for LDLM locks acquired by server-side OBDs.
+/**
+ * A helper to build a blocking ast function
+ *
+ * Perform a common operation for blocking asts:
+ * defferred lock cancellation.
+ *
+ * \param lock the lock blocking or canceling ast was called on
+ * \retval 0
+ * \see mdt_blocking_ast
+ * \see ldlm_blocking_ast
  */
-int ldlm_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
-                      void *data, int flag)
+int ldlm_blocking_ast_nocheck(struct ldlm_lock *lock)
 {
         int do_ast;
         ENTRY;
 
-        if (flag == LDLM_CB_CANCELING) {
-                /* Don't need to do anything here. */
-                RETURN(0);
-        }
-
-        lock_res_and_lock(lock);
-        /* Get this: if ldlm_blocking_ast is racing with intent_policy, such
-         * that ldlm_blocking_ast is called just before intent_policy method
-         * takes the ns_lock, then by the time we get the lock, we might not
-         * be the correct blocking function anymore.  So check, and return
-         * early, if so. */
-        if (lock->l_blocking_ast != ldlm_blocking_ast) {
-                unlock_res_and_lock(lock);
-                RETURN(0);
-        }
-
         lock->l_flags |= LDLM_FL_CBPENDING;
         do_ast = (!lock->l_readers && !lock->l_writers);
         unlock_res_and_lock(lock);
@@ -321,6 +307,42 @@ int ldlm_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
         RETURN(0);
 }
 
+/**
+ * Server blocking AST
+ *
+ * ->l_blocking_ast() callback for LDLM locks acquired by server-side
+ * OBDs.
+ *
+ * \param lock the lock which blocks a request or cancelling lock
+ * \param desc unused
+ * \param data unused
+ * \param flag indicates whether this cancelling or blocking callback
+ * \retval 0
+ * \see ldlm_blocking_ast_nocheck
+ */
+int ldlm_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
+                      void *data, int flag)
+{
+        ENTRY;
+
+        if (flag == LDLM_CB_CANCELING) {
+                /* Don't need to do anything here. */
+                RETURN(0);
+        }
+
+        lock_res_and_lock(lock);
+        /* Get this: if ldlm_blocking_ast is racing with intent_policy, such
+         * that ldlm_blocking_ast is called just before intent_policy method
+         * takes the ns_lock, then by the time we get the lock, we might not
+         * be the correct blocking function anymore.  So check, and return
+         * early, if so. */
+        if (lock->l_blocking_ast != ldlm_blocking_ast) {
+                unlock_res_and_lock(lock);
+                RETURN(0);
+        }
+        RETURN(ldlm_blocking_ast_nocheck(lock));
+}
+
 /*
  * ->l_glimpse_ast() for DLM extent locks acquired on the server-side. See
  * comment in filter_intent_policy() on why you may need this.
@@ -356,6 +378,7 @@ int ldlm_cli_enqueue_local(struct ldlm_namespace *ns,
                            ldlm_completion_callback completion,
                            ldlm_glimpse_callback glimpse,
                            void *data, __u32 lvb_len, void *lvb_swabber,
+                           const __u64 *client_cookie,
                            struct lustre_handle *lockh)
 {
         struct ldlm_lock *lock;
@@ -387,6 +410,8 @@ int ldlm_cli_enqueue_local(struct ldlm_namespace *ns,
         unlock_res_and_lock(lock);
         if (policy != NULL)
                 lock->l_policy_data = *policy;
+        if (client_cookie != NULL)
+                lock->l_client_cookie = *client_cookie;
         if (type == LDLM_EXTENT)
                 lock->l_req_extent = policy->l_extent;
 
@@ -406,7 +431,7 @@ int ldlm_cli_enqueue_local(struct ldlm_namespace *ns,
         LDLM_DEBUG(lock, "client-side local enqueue END");
         EXIT;
  out:
-        LDLM_LOCK_PUT(lock);
+        LDLM_LOCK_RELEASE(lock);
  out_nolock:
         return err;
 }
@@ -415,13 +440,31 @@ static void failed_lock_cleanup(struct ldlm_namespace *ns,
                                 struct ldlm_lock *lock,
                                 struct lustre_handle *lockh, int mode)
 {
+        int need_cancel = 0;
+
         /* Set a flag to prevent us from sending a CANCEL (bug 407) */
         lock_res_and_lock(lock);
-        lock->l_flags |= LDLM_FL_LOCAL_ONLY;
+        /* Check that lock is not granted or failed, we might race. */
+        if ((lock->l_req_mode != lock->l_granted_mode) &&
+            !(lock->l_flags & LDLM_FL_FAILED)) {
+                /* Make sure that this lock will not be found by raced
+                 * bl_ast and -EINVAL reply is sent to server anyways.
+                 * bug 17645 */
+                lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_FAILED |
+                                 LDLM_FL_ATOMIC_CB;
+                need_cancel = 1;
+        }
         unlock_res_and_lock(lock);
-        LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
 
-        ldlm_lock_decref_and_cancel(lockh, mode);
+        if (need_cancel) {
+                LDLM_DEBUG(lock,
+                           "setting FL_LOCAL_ONLY | LDLM_FL_FAILED | "
+                           "LDLM_FL_ATOMIC_CB");
+                ldlm_lock_decref_and_cancel(lockh, mode);
+        } else {
+                LDLM_DEBUG(lock, "lock was granted or failed in race");
+                ldlm_lock_decref(lockh, mode);
+        }
 
         /* XXX - HACK because we shouldn't call ldlm_lock_destroy()
          *       from llite/file.c/ll_file_flock(). */
@@ -595,7 +638,7 @@ cleanup:
                 failed_lock_cleanup(ns, lock, lockh, mode);
         /* Put lock 2 times, the second reference is held by ldlm_cli_enqueue */
         LDLM_LOCK_PUT(lock);
-        LDLM_LOCK_PUT(lock);
+        LDLM_LOCK_RELEASE(lock);
         return rc;
 }
 
@@ -607,7 +650,10 @@ static inline int ldlm_req_handles_avail(int req_size, int off)
         int avail;
 
         avail = min_t(int, LDLM_MAXREQSIZE, CFS_PAGE_SIZE - 512) - req_size;
-        avail /= sizeof(struct lustre_handle);
+        if (likely(avail >= 0))
+                avail /= (int)sizeof(struct lustre_handle);
+        else
+                avail = 0;
         avail += LDLM_LOCKREQ_HANDLES - off;
 
         return avail;
@@ -650,12 +696,12 @@ int ldlm_prep_elc_req(struct obd_export *exp, struct ptlrpc_request *req,
                 bufcount = req_capsule_filled_sizes(pill, RCL_CLIENT);
                 avail = ldlm_capsule_handles_avail(pill, RCL_CLIENT, canceloff);
 
-                flags = ns_connect_lru_resize(ns) ? 
+                flags = ns_connect_lru_resize(ns) ?
                         LDLM_CANCEL_LRUR : LDLM_CANCEL_AGED;
                 to_free = !ns_connect_lru_resize(ns) &&
                           opc == LDLM_ENQUEUE ? 1 : 0;
 
-                /* Cancel lru locks here _only_ if the server supports 
+                /* Cancel lru locks here _only_ if the server supports
                  * EARLY_CANCEL. Otherwise we have to send extra CANCEL
                  * rpc, what will make us slower. */
                 if (avail > count)
@@ -778,7 +824,7 @@ int ldlm_cli_enqueue(struct obd_export *exp, struct ptlrpc_request **reqp,
                                                 LDLM_ENQUEUE);
                 if (req == NULL) {
                         failed_lock_cleanup(ns, lock, lockh, einfo->ei_mode);
-                        LDLM_LOCK_PUT(lock);
+                        LDLM_LOCK_RELEASE(lock);
                         RETURN(-ENOMEM);
                 }
                 req_passed_in = 0;
@@ -829,7 +875,9 @@ int ldlm_cli_enqueue(struct obd_export *exp, struct ptlrpc_request **reqp,
         }
 
         LDLM_DEBUG(lock, "sending request");
+
         rc = ptlrpc_queue_wait(req);
+
         err = ldlm_cli_enqueue_fini(exp, req, einfo->ei_type, policy ? 1 : 0,
                                     einfo->ei_mode, flags, lvb, lvb_len,
                                     lvb_swabber, lockh, rc);
@@ -837,7 +885,7 @@ int ldlm_cli_enqueue(struct obd_export *exp, struct ptlrpc_request **reqp,
         /* If ldlm_cli_enqueue_fini did not find the lock, we need to free
          * one reference that we took */
         if (err == -ENOLCK)
-                LDLM_LOCK_PUT(lock);
+                LDLM_LOCK_RELEASE(lock);
         else
                 rc = err;
 
@@ -957,7 +1005,7 @@ static int ldlm_cli_cancel_local(struct ldlm_lock *lock)
 {
         int rc = LDLM_FL_LOCAL_ONLY;
         ENTRY;
-        
+
         if (lock->l_conn_export) {
                 int local_only;
 
@@ -1006,7 +1054,7 @@ static void ldlm_cancel_pack(struct ptlrpc_request *req,
         LASSERT(dlm != NULL);
 
         /* Check the room in the request buffer. */
-        max = req_capsule_get_size(&req->rq_pill, &RMF_DLM_REQ, RCL_CLIENT) - 
+        max = req_capsule_get_size(&req->rq_pill, &RMF_DLM_REQ, RCL_CLIENT) -
                 sizeof(struct ldlm_request);
         max /= sizeof(struct lustre_handle);
         max += LDLM_LOCKREQ_HANDLES;
@@ -1086,7 +1134,7 @@ int ldlm_cli_cancel_req(struct obd_export *exp, struct list_head *cancels,
 
                 ptlrpc_request_set_replen(req);
                 if (flags & LDLM_FL_ASYNC) {
-                        ptlrpcd_add_req(req);
+                        ptlrpcd_add_req(req, PSCOPE_OTHER);
                         sent = count;
                         GOTO(out, 0);
                 } else {
@@ -1132,28 +1180,27 @@ int ldlm_cli_update_pool(struct ptlrpc_request *req)
         __u64 old_slv, new_slv;
         __u32 new_limit;
         ENTRY;
-    
-        if (unlikely(!req->rq_import || !req->rq_import->imp_obd || 
+        if (unlikely(!req->rq_import || !req->rq_import->imp_obd ||
                      !imp_connect_lru_resize(req->rq_import)))
         {
-                /* 
-                 * Do nothing for corner cases. 
+                /*
+                 * Do nothing for corner cases.
                  */
                 RETURN(0);
         }
 
-        /* 
-         * In some cases RPC may contain slv and limit zeroed out. This is 
+        /*
+         * In some cases RPC may contain slv and limit zeroed out. This is
          * the case when server does not support lru resize feature. This is
          * also possible in some recovery cases when server side reqs have no
-         * ref to obd export and thus access to server side namespace is no 
-         * possible. 
+         * ref to obd export and thus access to server side namespace is no
+         * possible.
          */
-        if (lustre_msg_get_slv(req->rq_repmsg) == 0 || 
+        if (lustre_msg_get_slv(req->rq_repmsg) == 0 ||
             lustre_msg_get_limit(req->rq_repmsg) == 0) {
                 DEBUG_REQ(D_HA, req, "Zero SLV or Limit found "
-                          "(SLV: "LPU64", Limit: %u)", 
-                          lustre_msg_get_slv(req->rq_repmsg), 
+                          "(SLV: "LPU64", Limit: %u)",
+                          lustre_msg_get_slv(req->rq_repmsg),
                           lustre_msg_get_limit(req->rq_repmsg));
                 RETURN(0);
         }
@@ -1162,12 +1209,12 @@ int ldlm_cli_update_pool(struct ptlrpc_request *req)
         new_slv = lustre_msg_get_slv(req->rq_repmsg);
         obd = req->rq_import->imp_obd;
 
-        /* 
-         * Set new SLV and Limit to obd fields to make accessible for pool 
+        /*
+         * Set new SLV and Limit to obd fields to make accessible for 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 in cleanup time. Evil races are possible which may cause
-         * oops in that time. 
+         * oops in that time.
          */
         write_lock(&obd->obd_pool_lock);
         old_slv = obd->obd_pool_slv;
@@ -1189,7 +1236,7 @@ int ldlm_cli_cancel(struct lustre_handle *lockh)
         ENTRY;
 
         /* concurrent cancels on the same handle can happen */
-        lock = __ldlm_handle2lock(lockh, LDLM_FL_CANCELING);
+        lock = ldlm_handle2lock_long(lockh, LDLM_FL_CANCELING);
         if (lock == NULL) {
                 LDLM_DEBUG_NOLOCK("lock is already being destroyed\n");
                 RETURN(0);
@@ -1197,7 +1244,7 @@ int ldlm_cli_cancel(struct lustre_handle *lockh)
 
         rc = ldlm_cli_cancel_local(lock);
         if (rc < 0 || rc == LDLM_FL_LOCAL_ONLY) {
-                LDLM_LOCK_PUT(lock);
+                LDLM_LOCK_RELEASE(lock);
                 RETURN(rc < 0 ? rc : 0);
         }
         /* Even if the lock is marked as LDLM_FL_BL_AST, this is a LDLM_CANCEL
@@ -1252,7 +1299,7 @@ static int ldlm_cancel_list(struct list_head *cancels, int count, int flags)
                 if (rc == LDLM_FL_LOCAL_ONLY) {
                         /* CANCEL RPC should not be sent to server. */
                         list_del_init(&lock->l_bl_ast);
-                        LDLM_LOCK_PUT(lock);
+                        LDLM_LOCK_RELEASE(lock);
                         count--;
                 }
 
@@ -1265,71 +1312,6 @@ static int ldlm_cancel_list(struct list_head *cancels, int count, int flags)
         RETURN(count);
 }
 
-/** 
- * Callback function for shrink policy. Makes decision whether to keep
- * \a lock in LRU for current \a LRU size \a unused, added in current scan
- * \a added and number of locks to be preferably canceled \a count.
- *
- * \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
- *
- * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
- */
-static ldlm_policy_res_t ldlm_cancel_shrink_policy(struct ldlm_namespace *ns,
-                                                   struct ldlm_lock *lock,
-                                                   int unused, int added, 
-                                                   int count)
-{
-        int lock_cost;
-        __u64 page_nr;
-
-        /* 
-         * Stop lru processing when we reached passed @count or checked all 
-         * locks in lru. 
-         */
-        if (count && added >= count)
-                return LDLM_POLICY_KEEP_LOCK;
-
-        if (lock->l_resource->lr_type == LDLM_EXTENT) {
-                struct ldlm_extent *l_extent;
-
-                /* 
-                 * For all extent locks cost is 1 + number of pages in
-                 * their extent. 
-                 */
-                l_extent = &lock->l_policy_data.l_extent;
-                page_nr = (l_extent->end - l_extent->start);
-                do_div(page_nr, CFS_PAGE_SIZE);
-
-#ifdef __KERNEL__
-                /* 
-                 * XXX: In fact this is evil hack, we can't access inode
-                 * here. For doing it right we need somehow to have number
-                 * of covered by lock. This should be fixed later when 10718 
-                 * is landed. 
-                 */
-                if (lock->l_ast_data != NULL) {
-                        struct inode *inode = lock->l_ast_data;
-                        if (page_nr > inode->i_mapping->nrpages)
-                                page_nr = inode->i_mapping->nrpages;
-                }
-#endif
-                lock_cost = 1 + page_nr;
-        } else {
-                /* 
-                 * For all locks which are not extent ones cost is 1 
-                 */
-                lock_cost = 1;
-        }
-
-        /* 
-         * Keep all expensive locks in lru for the memory pressure time
-         * cancel policy. They anyways may be canceled by lru resize
-         * pplicy if they have not small enough CLV. 
-         */
-        return lock_cost > ns->ns_shrink_thumb ? 
-                LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
-}
-
 /**
  * Callback function for lru-resize policy. Makes decision whether to keep
  * \a lock in LRU for current \a LRU size \a unused, added in current scan
@@ -1340,8 +1322,8 @@ static ldlm_policy_res_t ldlm_cancel_shrink_policy(struct ldlm_namespace *ns,
  * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
  */
 static ldlm_policy_res_t ldlm_cancel_lrur_policy(struct ldlm_namespace *ns,
-                                                 struct ldlm_lock *lock, 
-                                                 int unused, int added, 
+                                                 struct ldlm_lock *lock,
+                                                 int unused, int added,
                                                  int count)
 {
         cfs_time_t cur = cfs_time_current();
@@ -1349,8 +1331,8 @@ static ldlm_policy_res_t ldlm_cancel_lrur_policy(struct ldlm_namespace *ns,
         __u64 slv, lvf, lv;
         cfs_time_t la;
 
-        /* 
-         * Stop lru processing when we reached passed @count or checked all 
+        /*
+         * Stop lru processing when we reached passed @count or checked all
          * locks in lru.
          */
         if (count && added >= count)
@@ -1358,20 +1340,20 @@ static ldlm_policy_res_t ldlm_cancel_lrur_policy(struct ldlm_namespace *ns,
 
         slv = ldlm_pool_get_slv(pl);
         lvf = ldlm_pool_get_lvf(pl);
-        la = cfs_duration_sec(cfs_time_sub(cur, 
+        la = cfs_duration_sec(cfs_time_sub(cur,
                               lock->l_last_used));
 
-        /* 
-         * Stop when slv is not yet come from server or lv is smaller than 
+        /*
+         * Stop when slv is not yet come from server or lv is smaller than
          * it is.
          */
         lv = lvf * la * unused;
-        
-        /* 
-         * Inform pool about current CLV to see it via proc. 
+
+        /*
+         * Inform pool about current CLV to see it via proc.
          */
         ldlm_pool_set_clv(pl, lv);
-        return (slv == 1 || lv < slv) ? 
+        return (slv == 1 || lv < slv) ?
                 LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
 }
 
@@ -1385,15 +1367,15 @@ static ldlm_policy_res_t ldlm_cancel_lrur_policy(struct ldlm_namespace *ns,
  * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
  */
 static ldlm_policy_res_t ldlm_cancel_passed_policy(struct ldlm_namespace *ns,
-                                                   struct ldlm_lock *lock, 
+                                                   struct ldlm_lock *lock,
                                                    int unused, int added,
                                                    int count)
 {
-        /* 
-         * Stop lru processing when we reached passed @count or checked all 
-         * locks in lru. 
+        /*
+         * Stop lru processing when we reached passed @count or checked all
+         * locks in lru.
          */
-        return (added >= count) ? 
+        return (added >= count) ?
                 LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
 }
 
@@ -1407,18 +1389,18 @@ static ldlm_policy_res_t ldlm_cancel_passed_policy(struct ldlm_namespace *ns,
  * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
  */
 static ldlm_policy_res_t ldlm_cancel_aged_policy(struct ldlm_namespace *ns,
-                                                 struct ldlm_lock *lock, 
+                                                 struct ldlm_lock *lock,
                                                  int unused, int added,
                                                  int count)
 {
-        /* 
-         * Stop lru processing if young lock is found and we reached passed 
-         * @count. 
+        /*
+         * Stop lru processing if young lock is found and we reached passed
+         * @count.
          */
-        return ((added >= count) && 
+        return ((added >= count) &&
                 cfs_time_before(cfs_time_current(),
                                 cfs_time_add(lock->l_last_used,
-                                             ns->ns_max_age))) ? 
+                                             ns->ns_max_age))) ?
                 LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
 }
 
@@ -1432,20 +1414,20 @@ static ldlm_policy_res_t ldlm_cancel_aged_policy(struct ldlm_namespace *ns,
  * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
  */
 static ldlm_policy_res_t ldlm_cancel_default_policy(struct ldlm_namespace *ns,
-                                                    struct ldlm_lock *lock, 
+                                                    struct ldlm_lock *lock,
                                                     int unused, int added,
                                                     int count)
 {
-        /* 
-         * Stop lru processing when we reached passed @count or checked all 
-         * locks in lru. 
+        /*
+         * Stop lru processing when we reached passed @count or checked all
+         * locks in lru.
          */
-        return (added >= count) ? 
+        return (added >= count) ?
                 LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
 }
 
-typedef ldlm_policy_res_t (*ldlm_cancel_lru_policy_t)(struct ldlm_namespace *, 
-                                                      struct ldlm_lock *, int, 
+typedef ldlm_policy_res_t (*ldlm_cancel_lru_policy_t)(struct ldlm_namespace *,
+                                                      struct ldlm_lock *, int,
                                                       int, int);
 
 static ldlm_cancel_lru_policy_t
@@ -1453,7 +1435,8 @@ ldlm_cancel_lru_policy(struct ldlm_namespace *ns, int flags)
 {
         if (ns_connect_lru_resize(ns)) {
                 if (flags & LDLM_CANCEL_SHRINK)
-                        return ldlm_cancel_shrink_policy;
+                        /* We kill passed number of old locks. */
+                        return ldlm_cancel_passed_policy;
                 else if (flags & LDLM_CANCEL_LRUR)
                         return ldlm_cancel_lrur_policy;
                 else if (flags & LDLM_CANCEL_PASSED)
@@ -1462,10 +1445,10 @@ ldlm_cancel_lru_policy(struct ldlm_namespace *ns, int flags)
                 if (flags & LDLM_CANCEL_AGED)
                         return ldlm_cancel_aged_policy;
         }
-        
+
         return ldlm_cancel_default_policy;
 }
+
 /* - Free space in lru for @count new locks,
  *   redundant unused locks are canceled locally;
  * - also cancel locally unused aged locks;
@@ -1508,7 +1491,7 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
 
         pf = ldlm_cancel_lru_policy(ns, flags);
         LASSERT(pf != NULL);
-        
+
         while (!list_empty(&ns->ns_unused_list)) {
                 /* For any flags, stop scanning if @max is reached. */
                 if (max && added >= max)
@@ -1528,6 +1511,10 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
                 if (&lock->l_lru == &ns->ns_unused_list)
                         break;
 
+                LDLM_LOCK_GET(lock);
+                spin_unlock(&ns->ns_unused_lock);
+                lu_ref_add(&lock->l_reference, __FUNCTION__, cfs_current());
+
                 /* Pass the lock through the policy filter and see if it
                  * should stay in lru.
                  *
@@ -1535,17 +1522,20 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
                  * we find a lock that should stay in the cache.
                  * We should take into account lock age anyway
                  * as new lock even if it is small of weight is
-                 * valuable resource. 
+                 * valuable resource.
                  *
                  * That is, for shrinker policy we drop only
                  * old locks, but additionally chose them by
-                 * their weight. Big extent locks will stay in 
+                 * their weight. Big extent locks will stay in
                  * the cache. */
-                if (pf(ns, lock, unused, added, count) == LDLM_POLICY_KEEP_LOCK)
+                if (pf(ns, lock, unused, added, count) ==
+                    LDLM_POLICY_KEEP_LOCK) {
+                        lu_ref_del(&lock->l_reference,
+                                   __FUNCTION__, cfs_current());
+                        LDLM_LOCK_RELEASE(lock);
+                        spin_lock(&ns->ns_unused_lock);
                         break;
-
-                LDLM_LOCK_GET(lock); /* dropped by bl thread */
-                spin_unlock(&ns->ns_unused_lock);
+                }
 
                 lock_res_and_lock(lock);
                 /* Check flags again under the lock. */
@@ -1557,7 +1547,9 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
                          * cancel by itseft or the lock is matched
                          * is already not unused. */
                         unlock_res_and_lock(lock);
-                        LDLM_LOCK_PUT(lock);
+                        lu_ref_del(&lock->l_reference,
+                                   __FUNCTION__, cfs_current());
+                        LDLM_LOCK_RELEASE(lock);
                         spin_lock(&ns->ns_unused_lock);
                         continue;
                 }
@@ -1565,8 +1557,8 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
 
                 /* If we have chosen to cancel this lock voluntarily, we
                  * better send cancel notification to server, so that it
-                 * frees appropriate state. This might lead to a race 
-                 * where while we are doing cancel here, server is also 
+                 * frees appropriate state. This might lead to a race
+                 * where while we are doing cancel here, server is also
                  * silently cancelling this lock. */
                 lock->l_flags &= ~LDLM_FL_CANCEL_ON_BLOCK;
 
@@ -1587,6 +1579,7 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
                 LASSERT(list_empty(&lock->l_bl_ast));
                 list_add(&lock->l_bl_ast, cancels);
                 unlock_res_and_lock(lock);
+                lu_ref_del(&lock->l_reference, __FUNCTION__, cfs_current());
                 spin_lock(&ns->ns_unused_lock);
                 added++;
                 unused--;
@@ -1595,50 +1588,11 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
         RETURN(ldlm_cancel_list(cancels, added, cancel_flags));
 }
 
-/* Returns number of locks which could be canceled next time when 
- * ldlm_cancel_lru() is called. Used from locks pool shrinker. */
-int ldlm_cancel_lru_estimate(struct ldlm_namespace *ns,
-                             int count, int max, int flags)
-{
-        ldlm_cancel_lru_policy_t pf;
-        struct ldlm_lock *lock;
-        int added = 0, unused;
-        ENTRY;
-
-        pf = ldlm_cancel_lru_policy(ns, flags);
-        LASSERT(pf != NULL);
-        spin_lock(&ns->ns_unused_lock);
-        unused = ns->ns_nr_unused;
-
-        list_for_each_entry(lock, &ns->ns_unused_list, l_lru) {
-                /* For any flags, stop scanning if @max is reached. */
-                if (max && added >= max)
-                        break;
-
-                /* Somebody is already doing CANCEL or there is a
-                 * blocking request will send cancel. Let's not count 
-                 * this lock. */
-                if ((lock->l_flags & LDLM_FL_CANCELING) ||
-                    (lock->l_flags & LDLM_FL_BL_AST)) 
-                        continue;
-
-                /* Pass the lock through the policy filter and see if it
-                 * should stay in lru. */
-                if (pf(ns, lock, unused, added, count) == LDLM_POLICY_KEEP_LOCK)
-                        break;
-
-                added++;
-                unused--;
-        }
-        spin_unlock(&ns->ns_unused_lock);
-        RETURN(added);
-}
-
 /* when called with LDLM_ASYNC the blocking callback will be handled
  * in a thread and this function will return after the thread has been
  * asked to call the callback.  when called with LDLM_SYNC the blocking
  * callback will be performed in this function. */
-int ldlm_cancel_lru(struct ldlm_namespace *ns, int nr, ldlm_sync_t sync, 
+int ldlm_cancel_lru(struct ldlm_namespace *ns, int nr, ldlm_sync_t sync,
                     int flags)
 {
         CFS_LIST_HEAD(cancels);
@@ -1655,8 +1609,8 @@ int ldlm_cancel_lru(struct ldlm_namespace *ns, int nr, ldlm_sync_t sync,
                         RETURN(count);
         }
 
-        /* If an error occured in ASYNC mode, or
-         * this is SYNC mode, cancel the list. */
+        /* If an error occured in ASYNC mode, or this is SYNC mode,
+         * cancel the list. */
         ldlm_cli_cancel_list(&cancels, count, NULL, 0);
         RETURN(count);
 }
@@ -1693,7 +1647,7 @@ int ldlm_cancel_resource_local(struct ldlm_resource *res,
 
                 /* If somebody is already doing CANCEL, or blocking ast came,
                  * skip this lock. */
-                if (lock->l_flags & LDLM_FL_BL_AST || 
+                if (lock->l_flags & LDLM_FL_BL_AST ||
                     lock->l_flags & LDLM_FL_CANCELING)
                         continue;
 
@@ -1721,10 +1675,10 @@ int ldlm_cancel_resource_local(struct ldlm_resource *res,
         RETURN(ldlm_cancel_list(cancels, count, cancel_flags));
 }
 
-/* If @req is NULL, send CANCEL request to server with handles of locks 
- * in the @cancels. If EARLY_CANCEL is not supported, send CANCEL requests 
+/* If @req is NULL, send CANCEL request to server with handles of locks
+ * in the @cancels. If EARLY_CANCEL is not supported, send CANCEL requests
  * separately per lock.
- * If @req is not NULL, put handles of locks in @cancels into the request 
+ * If @req is not NULL, put handles of locks in @cancels into the request
  * buffer at the offset @off.
  * Destroy @cancels at the end. */
 int ldlm_cli_cancel_list(struct list_head *cancels, int count,
@@ -1736,8 +1690,8 @@ int ldlm_cli_cancel_list(struct list_head *cancels, int count,
 
         if (list_empty(cancels) || count == 0)
                 RETURN(0);
-        
-        /* XXX: requests (both batched and not) could be sent in parallel. 
+
+        /* XXX: requests (both batched and not) could be sent in parallel.
          * Usually it is enough to have just 1 RPC, but it is possible that
          * there are to many locks to be cancelled in LRU or on a resource.
          * It would also speed up the case when the server does not support
@@ -1790,12 +1744,14 @@ int ldlm_cli_cancel_unused_resource(struct ldlm_namespace *ns,
                 RETURN(0);
         }
 
+        LDLM_RESOURCE_ADDREF(res);
         count = ldlm_cancel_resource_local(res, &cancels, policy, mode,
                                            0, flags, opaque);
         rc = ldlm_cli_cancel_list(&cancels, count, NULL, flags);
         if (rc != ELDLM_OK)
                 CERROR("ldlm_cli_cancel_unused_resource: %d\n", rc);
 
+        LDLM_RESOURCE_DELREF(res);
         ldlm_resource_putref(res);
         RETURN(0);
 }
@@ -1844,6 +1800,7 @@ int ldlm_cli_cancel_unused(struct ldlm_namespace *ns,
                         ldlm_resource_getref(res);
                         spin_unlock(&ns->ns_hash_lock);
 
+                        LDLM_RESOURCE_ADDREF(res);
                         rc = ldlm_cli_cancel_unused_resource(ns, &res->lr_name,
                                                              NULL, LCK_MINMODE,
                                                              flags, opaque);
@@ -1852,6 +1809,7 @@ int ldlm_cli_cancel_unused(struct ldlm_namespace *ns,
                                 CERROR("ldlm_cli_cancel_unused ("LPU64"): %d\n",
                                        res->lr_name.name[0], rc);
 
+                        LDLM_RESOURCE_DELREF(res);
                         spin_lock(&ns->ns_hash_lock);
                         tmp = tmp->next;
                         ldlm_resource_putref_locked(res);
@@ -1940,9 +1898,11 @@ int ldlm_namespace_foreach_res(struct ldlm_namespace *ns,
                         res = list_entry(tmp, struct ldlm_resource, lr_hash);
                         ldlm_resource_getref(res);
                         spin_unlock(&ns->ns_hash_lock);
+                        LDLM_RESOURCE_ADDREF(res);
 
                         rc = iter(res, closure);
 
+                        LDLM_RESOURCE_DELREF(res);
                         spin_lock(&ns->ns_hash_lock);
                         tmp = tmp->next;
                         ldlm_resource_putref_locked(res);
@@ -1974,7 +1934,9 @@ void ldlm_resource_iterate(struct ldlm_namespace *ns,
                 return;
         }
 
+        LDLM_RESOURCE_ADDREF(res);
         ldlm_resource_foreach(res, iter, data);
+        LDLM_RESOURCE_DELREF(res);
         ldlm_resource_putref(res);
         EXIT;
 }
@@ -1988,13 +1950,20 @@ static int ldlm_chain_lock_for_replay(struct ldlm_lock *lock, void *closure)
         /* we use l_pending_chain here, because it's unused on clients. */
         LASSERTF(list_empty(&lock->l_pending_chain),"lock %p next %p prev %p\n",
                  lock, &lock->l_pending_chain.next,&lock->l_pending_chain.prev);
-        /* bug 9573: don't replay locks left after eviction */
-        if (!(lock->l_flags & LDLM_FL_FAILED))
+        /* bug 9573: don't replay locks left after eviction, or
+         * bug 17614: locks being actively cancelled. Get a reference
+         * on a lock so that it does not disapear under us (e.g. due to cancel)
+         */
+        if (!(lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_CANCELING))) {
                 list_add(&lock->l_pending_chain, list);
+                LDLM_LOCK_GET(lock);
+        }
+
         return LDLM_ITER_CONTINUE;
 }
 
-static int replay_lock_interpret(struct ptlrpc_request *req,
+static int replay_lock_interpret(const struct lu_env *env,
+                                 struct ptlrpc_request *req,
                                  struct ldlm_async_args *aa, int rc)
 {
         struct lustre_handle  old_hash_key;
@@ -2026,10 +1995,10 @@ static int replay_lock_interpret(struct ptlrpc_request *req,
         lock->l_remote_handle = reply->lock_handle;
 
         /* Key change rehash lock in per-export hash with new key */
-       exp = req->rq_export;
+        exp = req->rq_export;
         if (exp && exp->exp_lock_hash)
                 lustre_hash_rehash_key(exp->exp_lock_hash, &old_hash_key,
-                                      &lock->l_remote_handle,
+                                       &lock->l_remote_handle,
                                        &lock->l_exp_hash);
 
         LDLM_DEBUG(lock, "replayed lock:");
@@ -2119,8 +2088,8 @@ static int replay_one_lock(struct obd_import *imp, struct ldlm_lock *lock)
         CLASSERT(sizeof(*aa) <= sizeof(req->rq_async_args));
         aa = ptlrpc_req_async_args(req);
         aa->lock_handle = body->lock_handle[0];
-        req->rq_interpret_reply = replay_lock_interpret;
-        ptlrpcd_add_req(req);
+        req->rq_interpret_reply = (ptlrpc_interpterer_t)replay_lock_interpret;
+        ptlrpcd_add_req(req, PSCOPE_OTHER);
 
         RETURN(0);
 }
@@ -2143,9 +2112,12 @@ int ldlm_replay_locks(struct obd_import *imp)
 
         list_for_each_entry_safe(lock, next, &list, l_pending_chain) {
                 list_del_init(&lock->l_pending_chain);
-                if (rc)
+                if (rc) {
+                        LDLM_LOCK_PUT(lock);
                         continue; /* or try to do the rest? */
+                }
                 rc = replay_one_lock(imp, lock);
+                LDLM_LOCK_PUT(lock);
         }
 
         atomic_dec(&imp->imp_replay_inflight);