RDMA/cm: Print the old state when cm_destroy_id gets timeout

The old state is helpful for debugging, as the current state is always
IB_CM_IDLE when timeout happens.

Fixes: 96d9cbe ("RDMA/cm: add timeout to cm_destroy_id wait")
Signed-off-by: Mark Zhang <markzhang@nvidia.com>
Link: https://lore.kernel.org/r/20240322112049.2022994-1-markzhang@nvidia.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

Author: MarkZhang81

drivers/infiniband/core/cm.c

@@ -1026,23 +1026,26 @@ static void cm_reset_to_idle(struct cm_id_private *cm_id_priv)
 	}
 }
 
-static noinline void cm_destroy_id_wait_timeout(struct ib_cm_id *cm_id)
+static noinline void cm_destroy_id_wait_timeout(struct ib_cm_id *cm_id,
+						enum ib_cm_state old_state)
 {
 	struct cm_id_private *cm_id_priv;
 
 	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
-	pr_err("%s: cm_id=%p timed out. state=%d refcnt=%d\n", __func__,
-	       cm_id, cm_id->state, refcount_read(&cm_id_priv->refcount));
+	pr_err("%s: cm_id=%p timed out. state %d -> %d, refcnt=%d\n", __func__,
+	       cm_id, old_state, cm_id->state, refcount_read(&cm_id_priv->refcount));
 }
 
 static void cm_destroy_id(struct ib_cm_id *cm_id, int err)
 {
 	struct cm_id_private *cm_id_priv;
+	enum ib_cm_state old_state;
 	struct cm_work *work;
 	int ret;
 
 	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
 	spin_lock_irq(&cm_id_priv->lock);
+	old_state = cm_id->state;
 retest:
 	switch (cm_id->state) {
 	case IB_CM_LISTEN:
@@ -1151,7 +1154,7 @@ static void cm_destroy_id(struct ib_cm_id *cm_id, int err)
 						  msecs_to_jiffies(
 						  CM_DESTROY_ID_WAIT_TIMEOUT));
 		if (!ret) /* timeout happened */
-			cm_destroy_id_wait_timeout(cm_id);
+			cm_destroy_id_wait_timeout(cm_id, old_state);
 	} while (!ret);
 
 	while ((work = cm_dequeue_work(cm_id_priv)) != NULL)