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LU-3032 ptlrpc: race in pinger (use-after-free situation)
[fs/lustre-release.git] / lustre / ptlrpc / pinger.c
index 3caf74e..06dc234 100644 (file)
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
  *
- * Portal-RPC reconnection and replay operations, for use in recovery.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
  *
- *  Copyright (c) 2003 Cluster File Systems, Inc.
- *   Authors: Phil Schwan <phil@clusterfs.com>
- *            Mike Shaver <shaver@clusterfs.com>
+ * 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
  *
- *   This file is part of Lustre, http://www.lustre.org.
+ * 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.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
  *
- *   Lustre is free software; you can redistribute it and/or
- *   modify it under the terms of version 2 of the GNU General Public
- *   License as published by the Free Software Foundation.
+ * Copyright (c) 2011, 2013, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
  *
- *   Lustre is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
+ * lustre/ptlrpc/pinger.c
  *
- *   You should have received a copy of the GNU General Public License
- *   along with Lustre; if not, write to the Free Software
- *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * Portal-RPC reconnection and replay operations, for use in recovery.
  */
 
 #ifndef __KERNEL__
 #include <liblustre.h>
 #else
-#include <linux/version.h>
-#include <asm/semaphore.h>
 #define DEBUG_SUBSYSTEM S_RPC
 #endif
 
-#include <linux/obd_support.h>
-#include <linux/obd_class.h>
+#include <obd_support.h>
+#include <obd_class.h>
 #include "ptlrpc_internal.h"
 
-#ifdef __KERNEL__
+static int suppress_pings;
+CFS_MODULE_PARM(suppress_pings, "i", int, 0644, "Suppress pings");
 
-static struct ptlrpc_thread *pinger_thread = NULL;
-static DECLARE_MUTEX(pinger_sem);
-static struct list_head pinger_imports = LIST_HEAD_INIT(pinger_imports);
+struct mutex pinger_mutex;
+static CFS_LIST_HEAD(pinger_imports);
+static cfs_list_t timeout_list = CFS_LIST_HEAD_INIT(timeout_list);
 
-static int ptlrpc_pinger_main(void *arg)
+int ptlrpc_pinger_suppress_pings()
+{
+       return suppress_pings;
+}
+EXPORT_SYMBOL(ptlrpc_pinger_suppress_pings);
+
+struct ptlrpc_request *
+ptlrpc_prep_ping(struct obd_import *imp)
+{
+        struct ptlrpc_request *req;
+
+        req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING,
+                                        LUSTRE_OBD_VERSION, OBD_PING);
+        if (req) {
+                ptlrpc_request_set_replen(req);
+                req->rq_no_resend = req->rq_no_delay = 1;
+        }
+        return req;
+}
+
+int ptlrpc_obd_ping(struct obd_device *obd)
 {
-        struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
-        struct ptlrpc_thread *thread = data->thread;
-        unsigned long flags;
+        int rc;
+        struct ptlrpc_request *req;
         ENTRY;
 
-        lock_kernel();
-        ptlrpc_daemonize();
+        req = ptlrpc_prep_ping(obd->u.cli.cl_import);
+        if (req == NULL)
+                RETURN(-ENOMEM);
+
+        req->rq_send_state = LUSTRE_IMP_FULL;
+
+        rc = ptlrpc_queue_wait(req);
+
+        ptlrpc_req_finished(req);
+
+        RETURN(rc);
+}
+EXPORT_SYMBOL(ptlrpc_obd_ping);
+
+int ptlrpc_ping(struct obd_import *imp)
+{
+        struct ptlrpc_request *req;
+        ENTRY;
+
+        req = ptlrpc_prep_ping(imp);
+        if (req == NULL) {
+                CERROR("OOM trying to ping %s->%s\n",
+                       imp->imp_obd->obd_uuid.uuid,
+                       obd2cli_tgt(imp->imp_obd));
+                RETURN(-ENOMEM);
+        }
+
+        DEBUG_REQ(D_INFO, req, "pinging %s->%s",
+                  imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+        ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
+
+        RETURN(0);
+}
+
+void ptlrpc_update_next_ping(struct obd_import *imp, int soon)
+{
+#ifdef ENABLE_PINGER
+        int time = soon ? PING_INTERVAL_SHORT : PING_INTERVAL;
+        if (imp->imp_state == LUSTRE_IMP_DISCON) {
+                int dtime = max_t(int, CONNECTION_SWITCH_MIN,
+                                  AT_OFF ? 0 :
+                                  at_get(&imp->imp_at.iat_net_latency));
+                time = min(time, dtime);
+        }
+        imp->imp_next_ping = cfs_time_shift(time);
+#endif /* ENABLE_PINGER */
+}
+
+void ptlrpc_ping_import_soon(struct obd_import *imp)
+{
+        imp->imp_next_ping = cfs_time_current();
+}
+
+static inline int imp_is_deactive(struct obd_import *imp)
+{
+        return (imp->imp_deactive ||
+                OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_IMP_DEACTIVE));
+}
+
+static inline int ptlrpc_next_reconnect(struct obd_import *imp)
+{
+        if (imp->imp_server_timeout)
+                return cfs_time_shift(obd_timeout / 2);
+        else
+                return cfs_time_shift(obd_timeout);
+}
+
+static cfs_atomic_t suspend_timeouts = CFS_ATOMIC_INIT(0);
+static cfs_time_t suspend_wakeup_time = 0;
+
+cfs_duration_t pinger_check_timeout(cfs_time_t time)
+{
+        struct timeout_item *item;
+        cfs_time_t timeout = PING_INTERVAL;
+
+        /* The timeout list is a increase order sorted list */
+       mutex_lock(&pinger_mutex);
+        cfs_list_for_each_entry(item, &timeout_list, ti_chain) {
+                int ti_timeout = item->ti_timeout;
+                if (timeout > ti_timeout)
+                        timeout = ti_timeout;
+                break;
+        }
+       mutex_unlock(&pinger_mutex);
+
+        return cfs_time_sub(cfs_time_add(time, cfs_time_seconds(timeout)),
+                                         cfs_time_current());
+}
 
-        SIGNAL_MASK_LOCK(current, flags);
-        sigfillset(&current->blocked);
-        RECALC_SIGPENDING;
-        SIGNAL_MASK_UNLOCK(current, flags);
+static cfs_waitq_t suspend_timeouts_waitq;
 
-        THREAD_NAME(current->comm, "%s", data->name);
-        unlock_kernel();
+cfs_time_t ptlrpc_suspend_wakeup_time(void)
+{
+        return suspend_wakeup_time;
+}
+
+void ptlrpc_deactivate_timeouts(struct obd_import *imp)
+{
+        /*XXX: disabled for now, will be replaced by adaptive timeouts */
+#if 0
+        if (imp->imp_no_timeout)
+                return;
+        imp->imp_no_timeout = 1;
+        cfs_atomic_inc(&suspend_timeouts);
+        CDEBUG(D_HA|D_WARNING, "deactivate timeouts %u\n",
+               cfs_atomic_read(&suspend_timeouts));
+#endif
+}
+
+void ptlrpc_activate_timeouts(struct obd_import *imp)
+{
+        /*XXX: disabled for now, will be replaced by adaptive timeouts */
+#if 0
+        if (!imp->imp_no_timeout)
+                return;
+        imp->imp_no_timeout = 0;
+        LASSERT(cfs_atomic_read(&suspend_timeouts) > 0);
+        if (cfs_atomic_dec_and_test(&suspend_timeouts)) {
+                suspend_wakeup_time = cfs_time_current();
+                cfs_waitq_signal(&suspend_timeouts_waitq);
+        }
+        CDEBUG(D_HA|D_WARNING, "activate timeouts %u\n",
+               cfs_atomic_read(&suspend_timeouts));
+#endif
+}
+
+int ptlrpc_check_suspend(void)
+{
+        if (cfs_atomic_read(&suspend_timeouts))
+                return 1;
+        return 0;
+}
+
+int ptlrpc_check_and_wait_suspend(struct ptlrpc_request *req)
+{
+        struct l_wait_info lwi;
+
+        if (cfs_atomic_read(&suspend_timeouts)) {
+                DEBUG_REQ(D_NET, req, "-- suspend %d regular timeout",
+                          cfs_atomic_read(&suspend_timeouts));
+                lwi = LWI_INTR(NULL, NULL);
+                l_wait_event(suspend_timeouts_waitq,
+                             cfs_atomic_read(&suspend_timeouts) == 0, &lwi);
+                DEBUG_REQ(D_NET, req, "-- recharge regular timeout");
+                return 1;
+        }
+        return 0;
+}
+
+#ifdef __KERNEL__
+
+static bool ir_up;
+
+void ptlrpc_pinger_ir_up(void)
+{
+       CDEBUG(D_HA, "IR up\n");
+       ir_up = true;
+}
+EXPORT_SYMBOL(ptlrpc_pinger_ir_up);
+
+void ptlrpc_pinger_ir_down(void)
+{
+       CDEBUG(D_HA, "IR down\n");
+       ir_up = false;
+}
+EXPORT_SYMBOL(ptlrpc_pinger_ir_down);
+
+static void ptlrpc_pinger_process_import(struct obd_import *imp,
+                                         unsigned long this_ping)
+{
+       int level;
+       int force;
+       int force_next;
+       int suppress;
+
+       spin_lock(&imp->imp_lock);
+
+       level = imp->imp_state;
+       force = imp->imp_force_verify;
+       force_next = imp->imp_force_next_verify;
+       /*
+        * This will be used below only if the import is "FULL".
+        */
+       suppress = ir_up && OCD_HAS_FLAG(&imp->imp_connect_data, PINGLESS);
+
+       imp->imp_force_verify = 0;
+
+       if (cfs_time_aftereq(imp->imp_next_ping - 5 * CFS_TICK, this_ping) &&
+           !force) {
+               spin_unlock(&imp->imp_lock);
+               return;
+       }
+
+       imp->imp_force_next_verify = 0;
+
+       spin_unlock(&imp->imp_lock);
+
+       CDEBUG(level == LUSTRE_IMP_FULL ? D_INFO : D_HA, "%s->%s: level %s/%u "
+              "force %u force_next %u deactive %u pingable %u suppress %u\n",
+              imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd),
+              ptlrpc_import_state_name(level), level, force, force_next,
+              imp->imp_deactive, imp->imp_pingable, suppress);
+
+        if (level == LUSTRE_IMP_DISCON && !imp_is_deactive(imp)) {
+                /* wait for a while before trying recovery again */
+                imp->imp_next_ping = ptlrpc_next_reconnect(imp);
+                if (!imp->imp_no_pinger_recover)
+                        ptlrpc_initiate_recovery(imp);
+        } else if (level != LUSTRE_IMP_FULL ||
+                   imp->imp_obd->obd_no_recov ||
+                   imp_is_deactive(imp)) {
+               CDEBUG(D_HA, "%s->%s: not pinging (in recovery "
+                      "or recovery disabled: %s)\n",
+                      imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd),
+                      ptlrpc_import_state_name(level));
+       } else if ((imp->imp_pingable && !suppress) || force_next || force) {
+               ptlrpc_ping(imp);
+       }
+}
+
+static int ptlrpc_pinger_main(void *arg)
+{
+        struct ptlrpc_thread *thread = (struct ptlrpc_thread *)arg;
+       ENTRY;
+
+        cfs_daemonize(thread->t_name);
 
         /* Record that the thread is running */
-        thread->t_flags = SVC_RUNNING;
-        wake_up(&thread->t_ctl_waitq);
+        thread_set_flags(thread, SVC_RUNNING);
+        cfs_waitq_signal(&thread->t_ctl_waitq);
 
         /* And now, loop forever, pinging as needed. */
         while (1) {
-                unsigned long this_ping = jiffies;
-                long time_to_next_ping;
-                struct l_wait_info lwi = LWI_TIMEOUT(obd_timeout * HZ,
-                                                     NULL, NULL);
-                struct ptlrpc_request_set *set;
-                struct ptlrpc_request *req;
-                struct list_head *iter;
-                wait_queue_t set_wait;
-                int rc;
-
-                set = ptlrpc_prep_set();
-                down(&pinger_sem);
-                list_for_each(iter, &pinger_imports) {
-                        struct obd_import *imp =
-                                list_entry(iter, struct obd_import,
-                                           imp_pinger_chain);
-                        int generation, level;
-                        unsigned long flags;
-
-                        if (imp->imp_next_ping <= this_ping) {
-                                /* Add a ping. */
-                                spin_lock_irqsave(&imp->imp_lock, flags);
-                                generation = imp->imp_generation;
-                                level = imp->imp_state;
-                                spin_unlock_irqrestore(&imp->imp_lock, flags);
-
-                                if (level != LUSTRE_IMP_FULL) {
-                                        CDEBUG(D_HA,
-                                               "not pinging %s (in recovery)\n",
-                                               imp->imp_target_uuid.uuid);
-                                        continue;
-                                }
-
-                                req = ptlrpc_prep_req(imp, OBD_PING, 0, NULL,
-                                                      NULL);
-                                if (!req) {
-                                        CERROR("OOM trying to ping\n");
-                                        break;
-                                }
-                                req->rq_no_resend = 1;
-                                req->rq_replen = lustre_msg_size(0, NULL);
-                                req->rq_send_state = LUSTRE_IMP_FULL;
-                                req->rq_phase = RQ_PHASE_RPC;
-                                req->rq_import_generation = generation;
-                                ptlrpc_set_add_req(set, req);
-                        } else {
-                                CDEBUG(D_HA, "don't need to ping %s (%lu > "
-                                       "%lu)\n", imp->imp_target_uuid.uuid,
-                                       imp->imp_next_ping, this_ping);
-                        }
-                }
-                up(&pinger_sem);
-
-                /* Might be empty, that's OK. */
-                if (set->set_remaining == 0)
-                        CDEBUG(D_HA, "nothing to ping\n");
-                list_for_each(iter, &set->set_requests) {
-                        struct ptlrpc_request *req =
-                                list_entry(iter, struct ptlrpc_request,
-                                           rq_set_chain);
-                        DEBUG_REQ(D_HA, req, "pinging %s->%s",
-                                  req->rq_import->imp_obd->obd_uuid.uuid,
-                                  req->rq_import->imp_target_uuid.uuid);
-                        (void)ptl_send_rpc(req);
-                }
+                cfs_time_t this_ping = cfs_time_current();
+                struct l_wait_info lwi;
+                cfs_duration_t time_to_next_wake;
+                struct timeout_item *item;
+                cfs_list_t *iter;
 
-                /* Have to wait on both the thread's queue and the set's. */
-                init_waitqueue_entry(&set_wait, current);
-                add_wait_queue(&set->set_waitq, &set_wait);
-                rc = l_wait_event(thread->t_ctl_waitq,
-                                  thread->t_flags & SVC_STOPPING ||
-                                  ptlrpc_check_set(set),
-                                  &lwi);
-                remove_wait_queue(&set->set_waitq, &set_wait);
-                CDEBUG(D_HA, "ping complete (%lu)\n", jiffies);
-
-                if (thread->t_flags & SVC_STOPPING) {
-                        thread->t_flags &= ~SVC_STOPPING;
-                        list_for_each(iter, &set->set_requests) {
-                                req = list_entry(iter, struct ptlrpc_request,
-                                                 rq_set_chain);
-                                if (!req->rq_replied)
-                                        ptlrpc_unregister_reply(req);
-                        }
-                        ptlrpc_set_destroy(set);
-                        EXIT;
-                        break;
+               mutex_lock(&pinger_mutex);
+                cfs_list_for_each_entry(item, &timeout_list, ti_chain) {
+                        item->ti_cb(item, item->ti_cb_data);
                 }
+                cfs_list_for_each(iter, &pinger_imports) {
+                        struct obd_import *imp =
+                                cfs_list_entry(iter, struct obd_import,
+                                               imp_pinger_chain);
 
-                /* Expire all the requests that didn't come back. */
-                down(&pinger_sem);
-                list_for_each(iter, &set->set_requests) {
-                        req = list_entry(iter, struct ptlrpc_request,
-                                         rq_set_chain);
-
-                        if (req->rq_replied)
-                                continue;
-
-                        req->rq_phase = RQ_PHASE_COMPLETE;
-                        set->set_remaining--;
-                        /* If it was disconnected, don't sweat it. */
-                        if (list_empty(&req->rq_import->imp_pinger_chain)) {
-                                ptlrpc_unregister_reply(req);
-                                continue;
-                        }
-
-                        ptlrpc_expire_one_request(req);
+                        ptlrpc_pinger_process_import(imp, this_ping);
+                        /* obd_timeout might have changed */
+                        if (imp->imp_pingable && imp->imp_next_ping &&
+                            cfs_time_after(imp->imp_next_ping,
+                                           cfs_time_add(this_ping,
+                                                        cfs_time_seconds(PING_INTERVAL))))
+                                ptlrpc_update_next_ping(imp, 0);
                 }
-                up(&pinger_sem);
-                ptlrpc_set_destroy(set);
+               mutex_unlock(&pinger_mutex);
+                /* update memory usage info */
+                obd_update_maxusage();
 
                 /* Wait until the next ping time, or until we're stopped. */
-                time_to_next_ping = this_ping + (obd_timeout * HZ) - jiffies;
-                CDEBUG(D_HA, "next ping in %lu (%lu)\n", time_to_next_ping,
-                       this_ping + (obd_timeout * HZ));
-                if (time_to_next_ping > 0) {
-                        lwi = LWI_TIMEOUT(time_to_next_ping, NULL, NULL);
+                time_to_next_wake = pinger_check_timeout(this_ping);
+                /* The ping sent by ptlrpc_send_rpc may get sent out
+                   say .01 second after this.
+                   ptlrpc_pinger_sending_on_import will then set the
+                   next ping time to next_ping + .01 sec, which means
+                   we will SKIP the next ping at next_ping, and the
+                   ping will get sent 2 timeouts from now!  Beware. */
+                CDEBUG(D_INFO, "next wakeup in "CFS_DURATION_T" ("
+                       CFS_TIME_T")\n", time_to_next_wake,
+                       cfs_time_add(this_ping,cfs_time_seconds(PING_INTERVAL)));
+                if (time_to_next_wake > 0) {
+                        lwi = LWI_TIMEOUT(max_t(cfs_duration_t,
+                                                time_to_next_wake,
+                                                cfs_time_seconds(1)),
+                                          NULL, NULL);
                         l_wait_event(thread->t_ctl_waitq,
-                                     thread->t_flags & (SVC_STOPPING|SVC_EVENT),
+                                     thread_is_stopping(thread) ||
+                                     thread_is_event(thread),
                                      &lwi);
-                        if (thread->t_flags & SVC_STOPPING) {
-                                thread->t_flags &= ~SVC_STOPPING;
+                        if (thread_test_and_clear_flags(thread, SVC_STOPPING)) {
                                 EXIT;
                                 break;
-                        } else if (thread->t_flags & SVC_EVENT) {
+                        } else {
                                 /* woken after adding import to reset timer */
-                                thread->t_flags &= ~SVC_EVENT;
+                                thread_test_and_clear_flags(thread, SVC_EVENT);
                         }
                 }
         }
 
-        thread->t_flags = SVC_STOPPED;
-        wake_up(&thread->t_ctl_waitq);
+        thread_set_flags(thread, SVC_STOPPED);
+        cfs_waitq_signal(&thread->t_ctl_waitq);
 
-        CDEBUG(D_NET, "pinger thread exiting, process %d\n", current->pid);
+        CDEBUG(D_NET, "pinger thread exiting, process %d\n", cfs_curproc_pid());
         return 0;
 }
 
+static struct ptlrpc_thread pinger_thread;
+
 int ptlrpc_start_pinger(void)
 {
-        struct l_wait_info lwi = { 0 };
-        struct ptlrpc_svc_data d;
-        int rc;
+       struct l_wait_info lwi = { 0 };
+       int rc;
 #ifndef ENABLE_PINGER
-        return 0;
+       return 0;
 #endif
-        ENTRY;
+       ENTRY;
 
-        if (pinger_thread != NULL)
-                RETURN(-EALREADY);
+       if (!thread_is_init(&pinger_thread) &&
+           !thread_is_stopped(&pinger_thread))
+               RETURN(-EALREADY);
 
-        OBD_ALLOC(pinger_thread, sizeof(*pinger_thread));
-        if (pinger_thread == NULL)
-                RETURN(-ENOMEM);
-        init_waitqueue_head(&pinger_thread->t_ctl_waitq);
+       cfs_waitq_init(&pinger_thread.t_ctl_waitq);
+       cfs_waitq_init(&suspend_timeouts_waitq);
 
-        d.name = "ll_ping";
-        d.thread = pinger_thread;
+       strcpy(pinger_thread.t_name, "ll_ping");
 
-        /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
-         * just drop the VM and FILES in ptlrpc_daemonize() right away. */
-        rc = kernel_thread(ptlrpc_pinger_main, &d, CLONE_VM | CLONE_FILES);
-        if (rc < 0) {
-                CERROR("cannot start thread: %d\n", rc);
-                OBD_FREE(pinger_thread, sizeof(*pinger_thread));
-                RETURN(rc);
-        }
-        l_wait_event(pinger_thread->t_ctl_waitq,
-                     pinger_thread->t_flags & SVC_RUNNING, &lwi);
+       /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
+        * just drop the VM and FILES in cfs_daemonize_ctxt() right away. */
+       rc = cfs_create_thread(ptlrpc_pinger_main,
+                              &pinger_thread, CFS_DAEMON_FLAGS);
+       if (rc < 0) {
+               CERROR("cannot start thread: %d\n", rc);
+               RETURN(rc);
+       }
+       l_wait_event(pinger_thread.t_ctl_waitq,
+                    thread_is_running(&pinger_thread), &lwi);
 
-        RETURN(rc);
+       if (suppress_pings)
+               CWARN("Pings will be suppressed at the request of the "
+                     "administrator.  The configuration shall meet the "
+                     "additional requirements described in the manual.  "
+                     "(Search for the \"suppress_pings\" kernel module "
+                     "parameter.)\n");
+
+       RETURN(0);
 }
 
+int ptlrpc_pinger_remove_timeouts(void);
+
 int ptlrpc_stop_pinger(void)
 {
-        struct l_wait_info lwi = { 0 };
-        int rc = 0;
+       struct l_wait_info lwi = { 0 };
 #ifndef ENABLE_PINGER
-        return 0;
+       return 0;
 #endif
-        ENTRY;
+       ENTRY;
 
-        if (pinger_thread == NULL)
-                RETURN(-EALREADY);
-        down(&pinger_sem);
-        pinger_thread->t_flags = SVC_STOPPING;
-        wake_up(&pinger_thread->t_ctl_waitq);
-        up(&pinger_sem);
+       if (thread_is_init(&pinger_thread) ||
+           thread_is_stopped(&pinger_thread))
+               RETURN(-EALREADY);
 
-        l_wait_event(pinger_thread->t_ctl_waitq,
-                     (pinger_thread->t_flags & SVC_STOPPED), &lwi);
+       ptlrpc_pinger_remove_timeouts();
 
-        OBD_FREE(pinger_thread, sizeof(*pinger_thread));
-        pinger_thread = NULL;
-        RETURN(rc);
+       thread_set_flags(&pinger_thread, SVC_STOPPING);
+       cfs_waitq_signal(&pinger_thread.t_ctl_waitq);
+
+       l_wait_event(pinger_thread.t_ctl_waitq,
+                    thread_is_stopped(&pinger_thread), &lwi);
+       RETURN(0);
 }
 
 void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
 {
-        down(&pinger_sem);
-        imp->imp_next_ping = jiffies + (obd_timeout * HZ);
-        up(&pinger_sem);
+        ptlrpc_update_next_ping(imp, 0);
+}
+EXPORT_SYMBOL(ptlrpc_pinger_sending_on_import);
+
+void ptlrpc_pinger_commit_expected(struct obd_import *imp)
+{
+       ptlrpc_update_next_ping(imp, 1);
+       LASSERT_SPIN_LOCKED(&imp->imp_lock);
+       /*
+        * Avoid reading stale imp_connect_data.  When not sure if pings are
+        * expected or not on next connection, we assume they are not and force
+        * one anyway to guarantee the chance of updating
+        * imp_peer_committed_transno.
+        */
+       if (imp->imp_state != LUSTRE_IMP_FULL ||
+           OCD_HAS_FLAG(&imp->imp_connect_data, PINGLESS))
+               imp->imp_force_next_verify = 1;
 }
 
 int ptlrpc_pinger_add_import(struct obd_import *imp)
 {
         ENTRY;
-        if (!list_empty(&imp->imp_pinger_chain))
+        if (!cfs_list_empty(&imp->imp_pinger_chain))
                 RETURN(-EALREADY);
 
-        down(&pinger_sem);
+       mutex_lock(&pinger_mutex);
         CDEBUG(D_HA, "adding pingable import %s->%s\n",
-               imp->imp_obd->obd_uuid.uuid, imp->imp_target_uuid.uuid);
-        imp->imp_next_ping = jiffies + (obd_timeout * HZ);
+               imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+        /* if we add to pinger we want recovery on this import */
+        imp->imp_obd->obd_no_recov = 0;
+        ptlrpc_update_next_ping(imp, 0);
         /* XXX sort, blah blah */
-        list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
+        cfs_list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
         class_import_get(imp);
 
-#ifdef ENABLE_PINGER
-        pinger_thread->t_flags |= SVC_EVENT;
-        wake_up(&pinger_thread->t_ctl_waitq);
-#endif
-        up(&pinger_sem);
+        ptlrpc_pinger_wake_up();
+       mutex_unlock(&pinger_mutex);
 
         RETURN(0);
 }
+EXPORT_SYMBOL(ptlrpc_pinger_add_import);
 
 int ptlrpc_pinger_del_import(struct obd_import *imp)
 {
         ENTRY;
-        if (list_empty(&imp->imp_pinger_chain))
+        if (cfs_list_empty(&imp->imp_pinger_chain))
                 RETURN(-ENOENT);
 
-        down(&pinger_sem);
-        list_del_init(&imp->imp_pinger_chain);
+       mutex_lock(&pinger_mutex);
+        cfs_list_del_init(&imp->imp_pinger_chain);
         CDEBUG(D_HA, "removing pingable import %s->%s\n",
-               imp->imp_obd->obd_uuid.uuid, imp->imp_target_uuid.uuid);
+               imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+        /* if we remove from pinger we don't want recovery on this import */
+        imp->imp_obd->obd_no_recov = 1;
         class_import_put(imp);
-        up(&pinger_sem);
+       mutex_unlock(&pinger_mutex);
+        RETURN(0);
+}
+EXPORT_SYMBOL(ptlrpc_pinger_del_import);
+
+/**
+ * Register a timeout callback to the pinger list, and the callback will
+ * be called when timeout happens.
+ */
+struct timeout_item* ptlrpc_new_timeout(int time, enum timeout_event event,
+                                        timeout_cb_t cb, void *data)
+{
+        struct timeout_item *ti;
+
+        OBD_ALLOC_PTR(ti);
+        if (!ti)
+                return(NULL);
+
+        CFS_INIT_LIST_HEAD(&ti->ti_obd_list);
+        CFS_INIT_LIST_HEAD(&ti->ti_chain);
+        ti->ti_timeout = time;
+        ti->ti_event = event;
+        ti->ti_cb = cb;
+        ti->ti_cb_data = data;
+
+        return ti;
+}
+
+/**
+ * Register timeout event on the the pinger thread.
+ * Note: the timeout list is an sorted list with increased timeout value.
+ */
+static struct timeout_item*
+ptlrpc_pinger_register_timeout(int time, enum timeout_event event,
+                               timeout_cb_t cb, void *data)
+{
+        struct timeout_item *item, *tmp;
+
+        LASSERT_MUTEX_LOCKED(&pinger_mutex);
+
+        cfs_list_for_each_entry(item, &timeout_list, ti_chain)
+                if (item->ti_event == event)
+                        goto out;
+
+        item = ptlrpc_new_timeout(time, event, cb, data);
+        if (item) {
+                cfs_list_for_each_entry_reverse(tmp, &timeout_list, ti_chain) {
+                        if (tmp->ti_timeout < time) {
+                                cfs_list_add(&item->ti_chain, &tmp->ti_chain);
+                                goto out;
+                        }
+                }
+                cfs_list_add(&item->ti_chain, &timeout_list);
+        }
+out:
+        return item;
+}
+
+/* Add a client_obd to the timeout event list, when timeout(@time)
+ * happens, the callback(@cb) will be called.
+ */
+int ptlrpc_add_timeout_client(int time, enum timeout_event event,
+                              timeout_cb_t cb, void *data,
+                              cfs_list_t *obd_list)
+{
+        struct timeout_item *ti;
+
+       mutex_lock(&pinger_mutex);
+        ti = ptlrpc_pinger_register_timeout(time, event, cb, data);
+        if (!ti) {
+               mutex_unlock(&pinger_mutex);
+                return (-EINVAL);
+        }
+        cfs_list_add(obd_list, &ti->ti_obd_list);
+       mutex_unlock(&pinger_mutex);
+        return 0;
+}
+EXPORT_SYMBOL(ptlrpc_add_timeout_client);
+
+int ptlrpc_del_timeout_client(cfs_list_t *obd_list,
+                              enum timeout_event event)
+{
+        struct timeout_item *ti = NULL, *item;
+
+        if (cfs_list_empty(obd_list))
+                return 0;
+       mutex_lock(&pinger_mutex);
+        cfs_list_del_init(obd_list);
+        /**
+         * If there are no obd attached to the timeout event
+         * list, remove this timeout event from the pinger
+         */
+        cfs_list_for_each_entry(item, &timeout_list, ti_chain) {
+                if (item->ti_event == event) {
+                        ti = item;
+                        break;
+                }
+        }
+        LASSERTF(ti != NULL, "ti is NULL ! \n");
+        if (cfs_list_empty(&ti->ti_obd_list)) {
+                cfs_list_del(&ti->ti_chain);
+                OBD_FREE_PTR(ti);
+        }
+       mutex_unlock(&pinger_mutex);
+        return 0;
+}
+EXPORT_SYMBOL(ptlrpc_del_timeout_client);
+
+int ptlrpc_pinger_remove_timeouts(void)
+{
+        struct timeout_item *item, *tmp;
+
+       mutex_lock(&pinger_mutex);
+        cfs_list_for_each_entry_safe(item, tmp, &timeout_list, ti_chain) {
+                LASSERT(cfs_list_empty(&item->ti_obd_list));
+                cfs_list_del(&item->ti_chain);
+                OBD_FREE_PTR(item);
+        }
+       mutex_unlock(&pinger_mutex);
+        return 0;
+}
+
+void ptlrpc_pinger_wake_up()
+{
+#ifdef ENABLE_PINGER
+       thread_add_flags(&pinger_thread, SVC_EVENT);
+       cfs_waitq_signal(&pinger_thread.t_ctl_waitq);
+#endif
+}
+
+/* Ping evictor thread */
+#define PET_READY     1
+#define PET_TERMINATE 2
+
+static int               pet_refcount = 0;
+static int               pet_state;
+static cfs_waitq_t       pet_waitq;
+CFS_LIST_HEAD(pet_list);
+static DEFINE_SPINLOCK(pet_lock);
+
+int ping_evictor_wake(struct obd_export *exp)
+{
+       struct obd_device *obd;
+
+       spin_lock(&pet_lock);
+       if (pet_state != PET_READY) {
+               /* eventually the new obd will call here again. */
+               spin_unlock(&pet_lock);
+               return 1;
+       }
+
+       obd = class_exp2obd(exp);
+       if (cfs_list_empty(&obd->obd_evict_list)) {
+               class_incref(obd, "evictor", obd);
+               cfs_list_add(&obd->obd_evict_list, &pet_list);
+       }
+       spin_unlock(&pet_lock);
+
+       cfs_waitq_signal(&pet_waitq);
+       return 0;
+}
+
+static int ping_evictor_main(void *arg)
+{
+        struct obd_device *obd;
+        struct obd_export *exp;
+        struct l_wait_info lwi = { 0 };
+        time_t expire_time;
+        ENTRY;
+
+        cfs_daemonize_ctxt("ll_evictor");
+
+        CDEBUG(D_HA, "Starting Ping Evictor\n");
+        pet_state = PET_READY;
+        while (1) {
+                l_wait_event(pet_waitq, (!cfs_list_empty(&pet_list)) ||
+                             (pet_state == PET_TERMINATE), &lwi);
+
+                /* loop until all obd's will be removed */
+                if ((pet_state == PET_TERMINATE) && cfs_list_empty(&pet_list))
+                        break;
+
+                /* we only get here if pet_exp != NULL, and the end of this
+                 * loop is the only place which sets it NULL again, so lock
+                 * is not strictly necessary. */
+               spin_lock(&pet_lock);
+               obd = cfs_list_entry(pet_list.next, struct obd_device,
+                                    obd_evict_list);
+               spin_unlock(&pet_lock);
+
+                expire_time = cfs_time_current_sec() - PING_EVICT_TIMEOUT;
+
+                CDEBUG(D_HA, "evicting all exports of obd %s older than %ld\n",
+                       obd->obd_name, expire_time);
+
+                /* Exports can't be deleted out of the list while we hold
+                 * the obd lock (class_unlink_export), which means we can't
+                 * lose the last ref on the export.  If they've already been
+                 * removed from the list, we won't find them here. */
+               spin_lock(&obd->obd_dev_lock);
+               while (!cfs_list_empty(&obd->obd_exports_timed)) {
+                       exp = cfs_list_entry(obd->obd_exports_timed.next,
+                                            struct obd_export,
+                                            exp_obd_chain_timed);
+                       if (expire_time > exp->exp_last_request_time) {
+                               class_export_get(exp);
+                               spin_unlock(&obd->obd_dev_lock);
+                               LCONSOLE_WARN("%s: haven't heard from client %s"
+                                              " (at %s) in %ld seconds. I think"
+                                              " it's dead, and I am evicting"
+                                              " it. exp %p, cur %ld expire %ld"
+                                              " last %ld\n",
+                                              obd->obd_name,
+                                              obd_uuid2str(&exp->exp_client_uuid),
+                                              obd_export_nid2str(exp),
+                                              (long)(cfs_time_current_sec() -
+                                                     exp->exp_last_request_time),
+                                              exp, (long)cfs_time_current_sec(),
+                                              (long)expire_time,
+                                              (long)exp->exp_last_request_time);
+                                CDEBUG(D_HA, "Last request was at %ld\n",
+                                       exp->exp_last_request_time);
+                                class_fail_export(exp);
+                                class_export_put(exp);
+                               spin_lock(&obd->obd_dev_lock);
+                       } else {
+                               /* List is sorted, so everyone below is ok */
+                               break;
+                       }
+               }
+               spin_unlock(&obd->obd_dev_lock);
+
+               spin_lock(&pet_lock);
+               cfs_list_del_init(&obd->obd_evict_list);
+               spin_unlock(&pet_lock);
+
+                class_decref(obd, "evictor", obd);
+        }
+        CDEBUG(D_HA, "Exiting Ping Evictor\n");
+
         RETURN(0);
 }
 
+void ping_evictor_start(void)
+{
+        int rc;
+
+        if (++pet_refcount > 1)
+                return;
+
+        cfs_waitq_init(&pet_waitq);
+
+        rc = cfs_create_thread(ping_evictor_main, NULL, CFS_DAEMON_FLAGS);
+        if (rc < 0) {
+                pet_refcount--;
+                CERROR("Cannot start ping evictor thread: %d\n", rc);
+        }
+}
+EXPORT_SYMBOL(ping_evictor_start);
+
+void ping_evictor_stop(void)
+{
+        if (--pet_refcount > 0)
+                return;
+
+        pet_state = PET_TERMINATE;
+        cfs_waitq_signal(&pet_waitq);
+}
+EXPORT_SYMBOL(ping_evictor_stop);
 #else /* !__KERNEL__ */
 
+/* XXX
+ * the current implementation of pinger in liblustre is not optimized
+ */
+
+#ifdef ENABLE_PINGER
+static struct pinger_data {
+        int             pd_recursion;
+        cfs_time_t      pd_this_ping;   /* jiffies */
+        cfs_time_t      pd_next_ping;   /* jiffies */
+        struct ptlrpc_request_set *pd_set;
+} pinger_args;
+
+static int pinger_check_rpcs(void *arg)
+{
+        cfs_time_t curtime = cfs_time_current();
+        struct ptlrpc_request *req;
+        struct ptlrpc_request_set *set;
+        cfs_list_t *iter;
+        struct obd_import *imp;
+        struct pinger_data *pd = &pinger_args;
+        int rc;
+
+        /* prevent recursion */
+        if (pd->pd_recursion++) {
+                CDEBUG(D_HA, "pinger: recursion! quit\n");
+                LASSERT(pd->pd_set);
+                pd->pd_recursion--;
+                return 0;
+        }
+
+        /* have we reached ping point? */
+        if (!pd->pd_set && cfs_time_before(curtime, pd->pd_next_ping)) {
+                pd->pd_recursion--;
+                return 0;
+        }
+
+        /* if we have rpc_set already, continue processing it */
+        if (pd->pd_set) {
+                LASSERT(pd->pd_this_ping);
+                set = pd->pd_set;
+                goto do_check_set;
+        }
+
+        pd->pd_this_ping = curtime;
+        pd->pd_set = ptlrpc_prep_set();
+        if (pd->pd_set == NULL)
+                goto out;
+        set = pd->pd_set;
+
+        /* add rpcs into set */
+       mutex_lock(&pinger_mutex);
+        cfs_list_for_each(iter, &pinger_imports) {
+                struct obd_import *imp = cfs_list_entry(iter, struct obd_import,
+                                                        imp_pinger_chain);
+                int generation, level;
+
+                if (cfs_time_aftereq(pd->pd_this_ping,
+                                     imp->imp_next_ping - 5 * CFS_TICK)) {
+                        /* Add a ping. */
+                       spin_lock(&imp->imp_lock);
+                       generation = imp->imp_generation;
+                       level = imp->imp_state;
+                       spin_unlock(&imp->imp_lock);
+
+                        if (level != LUSTRE_IMP_FULL) {
+                                CDEBUG(D_HA,
+                                       "not pinging %s (in recovery)\n",
+                                       obd2cli_tgt(imp->imp_obd));
+                                continue;
+                        }
+
+                        req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING,
+                                                        LUSTRE_OBD_VERSION,
+                                                        OBD_PING);
+                        if (req == NULL) {
+                                CERROR("OOM trying to ping %s->%s\n",
+                                       imp->imp_obd->obd_uuid.uuid,
+                                       obd2cli_tgt(imp->imp_obd));
+                                break;
+                        }
+
+                        req->rq_no_resend = 1;
+                        ptlrpc_request_set_replen(req);
+                        req->rq_send_state = LUSTRE_IMP_FULL;
+                        ptlrpc_rqphase_move(req, RQ_PHASE_RPC);
+                        req->rq_import_generation = generation;
+                        ptlrpc_set_add_req(set, req);
+                } else {
+                        CDEBUG(D_INFO, "don't need to ping %s ("CFS_TIME_T
+                               " > "CFS_TIME_T")\n", obd2cli_tgt(imp->imp_obd),
+                               imp->imp_next_ping, pd->pd_this_ping);
+                }
+        }
+        pd->pd_this_ping = curtime;
+       mutex_unlock(&pinger_mutex);
+
+        /* Might be empty, that's OK. */
+        if (cfs_atomic_read(&set->set_remaining) == 0)
+                CDEBUG(D_RPCTRACE, "nothing to ping\n");
+
+        cfs_list_for_each(iter, &set->set_requests) {
+                struct ptlrpc_request *req =
+                        cfs_list_entry(iter, struct ptlrpc_request,
+                                       rq_set_chain);
+                DEBUG_REQ(D_RPCTRACE, req, "pinging %s->%s",
+                          req->rq_import->imp_obd->obd_uuid.uuid,
+                          obd2cli_tgt(req->rq_import->imp_obd));
+                (void)ptl_send_rpc(req, 0);
+        }
+
+do_check_set:
+        rc = ptlrpc_check_set(NULL, set);
+
+        /* not finished, and we are not expired, simply return */
+        if (!rc && cfs_time_before(curtime, cfs_time_add(pd->pd_this_ping,
+                                            cfs_time_seconds(PING_INTERVAL)))) {
+                CDEBUG(D_RPCTRACE, "not finished, but also not expired\n");
+                pd->pd_recursion--;
+                return 0;
+        }
+
+        /* Expire all the requests that didn't come back. */
+       mutex_lock(&pinger_mutex);
+        cfs_list_for_each(iter, &set->set_requests) {
+                req = cfs_list_entry(iter, struct ptlrpc_request,
+                                     rq_set_chain);
+
+                if (req->rq_phase == RQ_PHASE_COMPLETE)
+                        continue;
+
+                CDEBUG(D_RPCTRACE, "Pinger initiate expire request(%p)\n",
+                       req);
+
+                /* This will also unregister reply. */
+                ptlrpc_expire_one_request(req, 0);
+
+                /* We're done with this req, let's finally move it to complete
+                 * phase and take care of inflights. */
+                ptlrpc_rqphase_move(req, RQ_PHASE_COMPLETE);
+                imp = req->rq_import;
+               spin_lock(&imp->imp_lock);
+               if (!cfs_list_empty(&req->rq_list)) {
+                       cfs_list_del_init(&req->rq_list);
+                       cfs_atomic_dec(&imp->imp_inflight);
+               }
+               spin_unlock(&imp->imp_lock);
+               cfs_atomic_dec(&set->set_remaining);
+       }
+       mutex_unlock(&pinger_mutex);
+
+        ptlrpc_set_destroy(set);
+        pd->pd_set = NULL;
+
+out:
+        pd->pd_next_ping = cfs_time_add(pd->pd_this_ping,
+                                        cfs_time_seconds(PING_INTERVAL));
+        pd->pd_this_ping = 0; /* XXX for debug */
+
+        CDEBUG(D_INFO, "finished a round ping\n");
+        pd->pd_recursion--;
+        return 0;
+}
+
+static void *pinger_callback = NULL;
+#endif /* ENABLE_PINGER */
+
 int ptlrpc_start_pinger(void)
 {
+#ifdef ENABLE_PINGER
+        memset(&pinger_args, 0, sizeof(pinger_args));
+        pinger_callback = liblustre_register_wait_callback("pinger_check_rpcs",
+                                                           &pinger_check_rpcs,
+                                                           &pinger_args);
+#endif
         return 0;
 }
 
 int ptlrpc_stop_pinger(void)
 {
+#ifdef ENABLE_PINGER
+        if (pinger_callback)
+                liblustre_deregister_wait_callback(pinger_callback);
+#endif
         return 0;
 }
 
-int ptlrpc_pinger_add_import(struct obd_import *imp)
+void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
+{
+#ifdef ENABLE_PINGER
+       mutex_lock(&pinger_mutex);
+        ptlrpc_update_next_ping(imp, 0);
+        if (pinger_args.pd_set == NULL &&
+            cfs_time_before(imp->imp_next_ping, pinger_args.pd_next_ping)) {
+                CDEBUG(D_HA, "set next ping to "CFS_TIME_T"(cur "CFS_TIME_T")\n",
+                        imp->imp_next_ping, cfs_time_current());
+                pinger_args.pd_next_ping = imp->imp_next_ping;
+        }
+       mutex_unlock(&pinger_mutex);
+#endif
+}
+
+void ptlrpc_pinger_commit_expected(struct obd_import *imp)
+{
+#ifdef ENABLE_PINGER
+       mutex_lock(&pinger_mutex);
+        ptlrpc_update_next_ping(imp, 1);
+        if (pinger_args.pd_set == NULL &&
+            cfs_time_before(imp->imp_next_ping, pinger_args.pd_next_ping)) {
+                CDEBUG(D_HA,"set next ping to "CFS_TIME_T"(cur "CFS_TIME_T")\n",
+                        imp->imp_next_ping, cfs_time_current());
+                pinger_args.pd_next_ping = imp->imp_next_ping;
+        }
+       mutex_unlock(&pinger_mutex);
+#endif
+}
+
+int ptlrpc_add_timeout_client(int time, enum timeout_event event,
+                              timeout_cb_t cb, void *data,
+                              cfs_list_t *obd_list)
 {
         return 0;
 }
 
-int ptlrpc_pinger_del_import(struct obd_import *imp)
+int ptlrpc_del_timeout_client(cfs_list_t *obd_list,
+                              enum timeout_event event)
 {
         return 0;
 }
 
-void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
+int ptlrpc_pinger_add_import(struct obd_import *imp)
+{
+        ENTRY;
+        if (!cfs_list_empty(&imp->imp_pinger_chain))
+                RETURN(-EALREADY);
+
+        CDEBUG(D_HA, "adding pingable import %s->%s\n",
+               imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+        ptlrpc_pinger_sending_on_import(imp);
+
+       mutex_lock(&pinger_mutex);
+        cfs_list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
+        class_import_get(imp);
+       mutex_unlock(&pinger_mutex);
+
+        RETURN(0);
+}
+
+int ptlrpc_pinger_del_import(struct obd_import *imp)
 {
+        ENTRY;
+        if (cfs_list_empty(&imp->imp_pinger_chain))
+                RETURN(-ENOENT);
+
+       mutex_lock(&pinger_mutex);
+        cfs_list_del_init(&imp->imp_pinger_chain);
+        CDEBUG(D_HA, "removing pingable import %s->%s\n",
+               imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+        class_import_put(imp);
+       mutex_unlock(&pinger_mutex);
+        RETURN(0);
 }
 
+void ptlrpc_pinger_wake_up()
+{
+#ifdef ENABLE_PINGER
+        /* XXX force pinger to run, if needed */
+        struct obd_import *imp;
+        ENTRY;
+        cfs_list_for_each_entry(imp, &pinger_imports, imp_pinger_chain) {
+                CDEBUG(D_RPCTRACE, "checking import %s->%s\n",
+                       imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
+#ifdef ENABLE_LIBLUSTRE_RECOVERY
+                if (imp->imp_state == LUSTRE_IMP_DISCON &&
+                    !imp_is_deactive(imp))
+#else
+                /*XXX only recover for the initial connection */
+                if (!lustre_handle_is_used(&imp->imp_remote_handle) &&
+                    imp->imp_state == LUSTRE_IMP_DISCON &&
+                    !imp_is_deactive(imp))
+#endif
+                        ptlrpc_initiate_recovery(imp);
+                else if (imp->imp_state != LUSTRE_IMP_FULL)
+                        CDEBUG(D_HA, "Refused to recover import %s->%s "
+                                     "state %d, deactive %d\n",
+                                     imp->imp_obd->obd_uuid.uuid,
+                                     obd2cli_tgt(imp->imp_obd), imp->imp_state,
+                                     imp_is_deactive(imp));
+        }
+        EXIT;
 #endif
+}
+#endif /* !__KERNEL__ */