Merge branch 'bpf-xdp-remove-xdp-flush'

Jesper Dangaard Brouer says:

====================
This patchset removes the net_device operation ndo_xdp_flush() call.
This is a follow merge commit ea9916ea3ed9 ("Merge branch
'ndo_xdp_xmit-cleanup'").  As after commit c1ece6b245bd ("bpf/xdp:
devmap can avoid calling ndo_xdp_flush") no callers of ndo_xdp_flush
are left in bpf-next tree.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -11883,7 +11883,6 @@ static const struct net_device_ops i40e_netdev_ops = {
 	.ndo_bridge_setlink	= i40e_ndo_bridge_setlink,
 	.ndo_bpf		= i40e_xdp,
 	.ndo_xdp_xmit		= i40e_xdp_xmit,
-	.ndo_xdp_flush		= i40e_xdp_flush,
 };
 
 /**

drivers/net/ethernet/intel/i40e/i40e_txrx.c

@@ -3707,22 +3707,3 @@ int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 
 	return n - drops;
 }
-
-/**
- * i40e_xdp_flush - Implements ndo_xdp_flush
- * @dev: netdev
- **/
-void i40e_xdp_flush(struct net_device *dev)
-{
-	struct i40e_netdev_priv *np = netdev_priv(dev);
-	unsigned int queue_index = smp_processor_id();
-	struct i40e_vsi *vsi = np->vsi;
-
-	if (test_bit(__I40E_VSI_DOWN, vsi->state))
-		return;
-
-	if (!i40e_enabled_xdp_vsi(vsi) || queue_index >= vsi->num_queue_pairs)
-		return;
-
-	i40e_xdp_ring_update_tail(vsi->xdp_rings[queue_index]);
-}

drivers/net/ethernet/intel/i40e/i40e_txrx.h

@@ -489,7 +489,6 @@ int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size);
 bool __i40e_chk_linearize(struct sk_buff *skb);
 int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 		  u32 flags);
-void i40e_xdp_flush(struct net_device *dev);
 
 /**
  * i40e_get_head - Retrieve head from head writeback

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -10069,26 +10069,6 @@ static int ixgbe_xdp_xmit(struct net_device *dev, int n,
 	return n - drops;
 }
 
-static void ixgbe_xdp_flush(struct net_device *dev)
-{
-	struct ixgbe_adapter *adapter = netdev_priv(dev);
-	struct ixgbe_ring *ring;
-
-	/* Its possible the device went down between xdp xmit and flush so
-	 * we need to ensure device is still up.
-	 */
-	if (unlikely(test_bit(__IXGBE_DOWN, &adapter->state)))
-		return;
-
-	ring = adapter->xdp_prog ? adapter->xdp_ring[smp_processor_id()] : NULL;
-	if (unlikely(!ring))
-		return;
-
-	ixgbe_xdp_ring_update_tail(ring);
-
-	return;
-}
-
 static const struct net_device_ops ixgbe_netdev_ops = {
 	.ndo_open		= ixgbe_open,
 	.ndo_stop		= ixgbe_close,
@@ -10136,7 +10116,6 @@ static const struct net_device_ops ixgbe_netdev_ops = {
 	.ndo_features_check	= ixgbe_features_check,
 	.ndo_bpf		= ixgbe_xdp,
 	.ndo_xdp_xmit		= ixgbe_xdp_xmit,
-	.ndo_xdp_flush		= ixgbe_xdp_flush,
 };
 
 /**

drivers/net/tun.c

@@ -1347,26 +1347,7 @@ static int tun_xdp_tx(struct net_device *dev, struct xdp_buff *xdp)
 	if (unlikely(!frame))
 		return -EOVERFLOW;
 
-	return tun_xdp_xmit(dev, 1, &frame, 0);
-}
-
-static void tun_xdp_flush(struct net_device *dev)
-{
-	struct tun_struct *tun = netdev_priv(dev);
-	struct tun_file *tfile;
-	u32 numqueues;
-
-	rcu_read_lock();
-
-	numqueues = READ_ONCE(tun->numqueues);
-	if (!numqueues)
-		goto out;
-
-	tfile = rcu_dereference(tun->tfiles[smp_processor_id() %
-					    numqueues]);
-	__tun_xdp_flush_tfile(tfile);
-out:
-	rcu_read_unlock();
+	return tun_xdp_xmit(dev, 1, &frame, XDP_XMIT_FLUSH);
 }
 
 static const struct net_device_ops tap_netdev_ops = {
@@ -1387,7 +1368,6 @@ static const struct net_device_ops tap_netdev_ops = {
 	.ndo_get_stats64	= tun_net_get_stats64,
 	.ndo_bpf		= tun_xdp,
 	.ndo_xdp_xmit		= tun_xdp_xmit,
-	.ndo_xdp_flush		= tun_xdp_flush,
 };
 
 static void tun_flow_init(struct tun_struct *tun)
@@ -1706,7 +1686,6 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 			alloc_frag->offset += buflen;
 			if (tun_xdp_tx(tun->dev, &xdp))
 				goto err_redirect;
-			tun_xdp_flush(tun->dev);
 			rcu_read_unlock();
 			preempt_enable();
 			return NULL;

drivers/net/virtio_net.c

@@ -407,18 +407,6 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,
 	return skb;
 }
 
-static void virtnet_xdp_flush(struct net_device *dev)
-{
-	struct virtnet_info *vi = netdev_priv(dev);
-	struct send_queue *sq;
-	unsigned int qp;
-
-	qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
-	sq = &vi->sq[qp];
-
-	virtqueue_kick(sq->vq);
-}
-
 static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
 				   struct send_queue *sq,
 				   struct xdp_frame *xdpf)
@@ -2359,7 +2347,6 @@ static const struct net_device_ops virtnet_netdev = {
 #endif
 	.ndo_bpf		= virtnet_xdp,
 	.ndo_xdp_xmit		= virtnet_xdp_xmit,
-	.ndo_xdp_flush		= virtnet_xdp_flush,
 	.ndo_features_check	= passthru_features_check,
 };
 

include/linux/netdevice.h

@@ -1192,9 +1192,6 @@ struct dev_ifalias {
  *	that got dropped are freed/returned via xdp_return_frame().
  *	Returns negative number, means general error invoking ndo, meaning
  *	no frames were xmit'ed and core-caller will free all frames.
- * void (*ndo_xdp_flush)(struct net_device *dev);
- *	This function is used to inform the driver to flush a particular
- *	xdp tx queue. Must be called on same CPU as xdp_xmit.
  */
 struct net_device_ops {
 	int			(*ndo_init)(struct net_device *dev);
@@ -1382,7 +1379,6 @@ struct net_device_ops {
 	int			(*ndo_xdp_xmit)(struct net_device *dev, int n,
 						struct xdp_frame **xdp,
 						u32 flags);
-	void			(*ndo_xdp_flush)(struct net_device *dev);
 };
 
 /**