b=24320 do not fork a new thread in mem pressure

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

diff --git a/lustre/ldlm/ldlm_lockd.c b/lustre/ldlm/ldlm_lockd.c
index 14fe1c9..f5fc1f8 100644 (file)
--- a/lustre/ldlm/ldlm_lockd.c
+++ b/lustre/ldlm/ldlm_lockd.c
@@ -851,10 +851,10 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
         if (lock->l_resource->lr_lvb_len) {
                 void *lvb = req_capsule_client_get(&req->rq_pill, &RMF_DLM_LVB);
 
-                lock_res_and_lock(lock);
+                cfs_down(&lock->l_resource->lr_lvb_sem);
                 memcpy(lvb, lock->l_resource->lr_lvb_data,
                        lock->l_resource->lr_lvb_len);
-                unlock_res_and_lock(lock);
+                cfs_up(&lock->l_resource->lr_lvb_sem);
         }
 
         LDLM_DEBUG(lock, "server preparing completion AST (after %lds wait)",
@@ -1115,10 +1115,12 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
         LDLM_DEBUG(lock, "server-side enqueue handler, new lock created");
 
         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_ENQUEUE_BLOCKED, obd_timeout * 2);
-        /* Don't enqueue a lock onto the export if it has already
-         * been evicted.  Cancel it now instead. (bug 3822) */
-        if (req->rq_export->exp_failed) {
-                LDLM_ERROR(lock, "lock on destroyed export %p", req->rq_export);
+        /* Don't enqueue a lock onto the export if it is been disonnected
+         * due to eviction (bug 3822) or server umount (bug 24324).
+         * Cancel it now instead. */
+        if (req->rq_export->exp_disconnected) {
+                LDLM_ERROR(lock, "lock on disconnected export %p",
+                           req->rq_export);
                 GOTO(out, rc = -ENOTCONN);
         }
 
@@ -1135,13 +1137,11 @@ existing_lock:
                  * local_lock_enqueue by the policy function. */
                 cookie = req;
         } else {
-                lock_res_and_lock(lock);
                 if (lock->l_resource->lr_lvb_len) {
                         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB,
                                              RCL_SERVER,
                                              lock->l_resource->lr_lvb_len);
                 }
-                unlock_res_and_lock(lock);
 
                 if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_ENQUEUE_EXTENT_ERR))
                         GOTO(out, rc = -ENOMEM);
@@ -1175,9 +1175,10 @@ existing_lock:
         dlm_rep->lock_flags |= dlm_req->lock_flags & LDLM_INHERIT_FLAGS;
         lock->l_flags |= dlm_req->lock_flags & LDLM_INHERIT_FLAGS;
 
-        /* Don't move a pending lock onto the export if it has already
-         * been evicted.  Cancel it now instead. (bug 5683) */
-        if (unlikely(req->rq_export->exp_failed ||
+        /* Don't move a pending lock onto the export if it has already been
+         * disconnected due to eviction (bug 5683) or server umount (bug 24324).
+         * Cancel it now instead. */
+        if (unlikely(req->rq_export->exp_disconnected ||
                      OBD_FAIL_CHECK(OBD_FAIL_LDLM_ENQUEUE_OLD_EXPORT))) {
                 LDLM_ERROR(lock, "lock on destroyed export %p", req->rq_export);
                 rc = -ENOTCONN;
@@ -1241,7 +1242,6 @@ existing_lock:
                 LDLM_DEBUG(lock, "server-side enqueue handler, sending reply"
                            "(err=%d, rc=%d)", err, rc);
 
-                lock_res_and_lock(lock);
                 if (rc == 0) {
                         if (lock->l_resource->lr_lvb_len > 0) {
                                 void *lvb;
@@ -1251,14 +1251,17 @@ existing_lock:
                                 LASSERTF(lvb != NULL, "req %p, lock %p\n",
                                          req, lock);
 
+                                cfs_down(&lock->l_resource->lr_lvb_sem);
                                 memcpy(lvb, lock->l_resource->lr_lvb_data,
                                        lock->l_resource->lr_lvb_len);
+                                cfs_up(&lock->l_resource->lr_lvb_sem);
                         }
                 } else {
+                        lock_res_and_lock(lock);
                         ldlm_resource_unlink_lock(lock);
                         ldlm_lock_destroy_nolock(lock);
+                        unlock_res_and_lock(lock);
                 }
-                unlock_res_and_lock(lock);
 
                 if (!err && dlm_req->lock_desc.l_resource.lr_type != LDLM_FLOCK)
                         ldlm_reprocess_all(lock->l_resource);
@@ -2215,7 +2218,8 @@ static int ldlm_bl_thread_main(void *arg)
 
                         /* Not fatal if racy and have a few too many threads */
                         if (unlikely(busy < blp->blp_max_threads &&
-                            busy >= cfs_atomic_read(&blp->blp_num_threads)))
+                            busy >= cfs_atomic_read(&blp->blp_num_threads) &&
+                            !blwi->blwi_mem_pressure))
                                 /* discard the return value, we tried */
                                 ldlm_bl_thread_start(blp);
                 } else {