drbd: Remove the unused hash tables

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 2b83aaf..1ddf6b6 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -122,10 +122,13 @@
 	list_del(&e->w.list); /* has been on active_ee or sync_ee */
 	list_add_tail(&e->w.list, &mdev->done_ee);
 
-	/* No hlist_del_init(&e->collision) here, we did not send the Ack yet,
-	 * neither did we wake possibly waiting conflicting requests.
-	 * done from "drbd_process_done_ee" within the appropriate w.cb
-	 * (e_end_block/e_end_resync_block) or from _drbd_clear_done_ee */
+	/*
+	 * Do not remove from the epoch_entries tree here: we did not send the
+	 * Ack yet and did not wake possibly waiting conflicting requests.
+	 * Removed from the tree from "drbd_process_done_ee" within the
+	 * appropriate w.cb (e_end_block/e_end_resync_block) or from
+	 * _drbd_clear_done_ee.
+	 */
 
 	do_wake = list_empty(block_id == ID_SYNCER ? &mdev->sync_ee : &mdev->active_ee);