From: panda <panda>
Date: Thu, 19 Nov 2009 11:28:16 +0000 (+0000)
Subject: b=21150
X-Git-Tag: GIT_EPOCH_B_HD_KDMU~70
X-Git-Url: https://git.whamcloud.com/gitweb?a=commitdiff_plain;h=af8bcd8339128470065d4b2e06bda94a1ce4adad;p=fs%2Flustre-release.git

b=21150
i=Johann Lombardi
i=ZhiYong Tian

avoid mds-lov cleanup during dqacq
---

diff --git a/lustre/include/obd.h b/lustre/include/obd.h
index 03ef1b3..0353146 100644
--- a/lustre/include/obd.h
+++ b/lustre/include/obd.h
@@ -1073,6 +1073,7 @@ struct obd_device {
         struct lvfs_run_ctxt    obd_lvfs_ctxt;
         struct obd_llog_group   obd_olg; /* default llog group */
         struct obd_device       *obd_observer;
+        struct rw_semaphore     obd_observer_link_sem;
         struct obd_notify_upcall obd_upcall;
         struct obd_export       *obd_self_export;
         /* list of exports in LRU order, for ping evictor, with obd_dev_lock */
diff --git a/lustre/include/obd_class.h b/lustre/include/obd_class.h
index 9cadd6b..e1e4bc5 100644
--- a/lustre/include/obd_class.h
+++ b/lustre/include/obd_class.h
@@ -1643,9 +1643,34 @@ static inline int obd_register_observer(struct obd_device *obd,
 {
         ENTRY;
         OBD_CHECK_DEV(obd);
-        if (obd->obd_observer && observer)
+        down_write(&obd->obd_observer_link_sem);
+        if (obd->obd_observer && observer) {
+                up_write(&obd->obd_observer_link_sem);
                 RETURN(-EALREADY);
+        }
         obd->obd_observer = observer;
+        up_write(&obd->obd_observer_link_sem);
+        RETURN(0);
+}
+
+static inline int obd_pin_observer(struct obd_device *obd,
+                                   struct obd_device **observer)
+{
+        ENTRY;
+        down_read(&obd->obd_observer_link_sem);
+        if (!obd->obd_observer) {
+                *observer = NULL;
+                up_read(&obd->obd_observer_link_sem);
+                RETURN(-ENOENT);
+        }
+        *observer = obd->obd_observer;
+        RETURN(0);
+}
+
+static inline int obd_unpin_observer(struct obd_device *obd)
+{
+        ENTRY;
+        up_read(&obd->obd_observer_link_sem);
         RETURN(0);
 }
 
diff --git a/lustre/ldlm/ldlm_lib.c b/lustre/ldlm/ldlm_lib.c
index 5ee1516..a889f18 100644
--- a/lustre/ldlm/ldlm_lib.c
+++ b/lustre/ldlm/ldlm_lib.c
@@ -2252,7 +2252,7 @@ int target_handle_dqacq_callback(struct ptlrpc_request *req)
 {
 #ifdef __KERNEL__
         struct obd_device *obd = req->rq_export->exp_obd;
-        struct obd_device *master_obd;
+        struct obd_device *master_obd = NULL, *lov_obd = NULL;
         struct obd_device_target *obt;
         struct lustre_quota_ctxt *qctxt;
         struct qunit_data *qdata = NULL;
@@ -2279,13 +2279,13 @@ int target_handle_dqacq_callback(struct ptlrpc_request *req)
         }
 
         /* we use the observer */
-        if (!obd->obd_observer || !obd->obd_observer->obd_observer) {
+        if (obd_pin_observer(obd, &lov_obd) ||
+            obd_pin_observer(lov_obd, &master_obd)) {
                 CERROR("Can't find the observer, it is recovering\n");
                 req->rq_status = -EAGAIN;
                 GOTO(out, rc);
         }
 
-        master_obd = obd->obd_observer->obd_observer;
         obt = &master_obd->u.obt;
         qctxt = &obt->obt_qctxt;
 
@@ -2331,6 +2331,11 @@ int target_handle_dqacq_callback(struct ptlrpc_request *req)
         EXIT;
 
 out:
+        if (master_obd)
+                obd_unpin_observer(lov_obd);
+        if (lov_obd)
+                obd_unpin_observer(obd);
+
         rc = ptlrpc_reply(req);
         return rc;
 #else
diff --git a/lustre/obdclass/obd_config.c b/lustre/obdclass/obd_config.c
index 2ee0fe3..779d0d3 100644
--- a/lustre/obdclass/obd_config.c
+++ b/lustre/obdclass/obd_config.c
@@ -268,6 +268,7 @@ int class_attach(struct lustre_cfg *lcfg)
         obd->obd_osfs_age = cfs_time_shift_64(-1000);
 
         /* XXX belongs in setup not attach  */
+        init_rwsem(&obd->obd_observer_link_sem);
         /* recovery data */
         cfs_init_timer(&obd->obd_recovery_timer);
         spin_lock_init(&obd->obd_processing_task_lock);