drbd: consistently use list_add_tail for peer_request tracking

Keep the epoch entry lists (active_ee, read_ee, sync_ee, ...)
consistently "oldest first".  That way finding the oldest not yet
successfully processed request is simply list_first_entry_or_null.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

2 files changed, 3 insertions, 3 deletions

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 3a3c4893ea26..db5c58042734 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -1777,7 +1777,7 @@ static int recv_resync_read(struct drbd_peer_device *peer_device, sector_t secto
         peer_req->w.cb = e_end_resync_block;
 
         spin_lock_irq(&device->resource->req_lock);
-        list_add(&peer_req->w.list, &device->sync_ee);
+        list_add_tail(&peer_req->w.list, &device->sync_ee);
         spin_unlock_irq(&device->resource->req_lock);
 
         atomic_add(pi->size >> 9, &device->rs_sect_ev);
@@ -2341,7 +2341,7 @@ static int receive_Data(struct drbd_connection *connection, struct packet_info *
          * active_ee to become empty in drbd_submit_peer_request();
          * better not add ourselves here. */
         if ((peer_req->flags & EE_IS_TRIM_USE_ZEROOUT) == 0)
-                list_add(&peer_req->w.list, &device->active_ee);
+                list_add_tail(&peer_req->w.list, &device->active_ee);
         spin_unlock_irq(&device->resource->req_lock);
 
         if (device->state.conn == C_SYNC_TARGET)
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 49b88731b349..ad57129289b5 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -410,7 +410,7 @@ static int read_for_csum(struct drbd_peer_device *peer_device, sector_t sector,
 
         peer_req->w.cb = w_e_send_csum;
         spin_lock_irq(&device->resource->req_lock);
-        list_add(&peer_req->w.list, &device->read_ee);
+        list_add_tail(&peer_req->w.list, &device->read_ee);
         spin_unlock_irq(&device->resource->req_lock);
 
         atomic_add(size >> 9, &device->rs_sect_ev);