iavf: drop page splitting and recycling

As an intermediate step, remove all page splitting/recycling code. Just
always allocate a new page and don't touch its refcount, so that it gets
freed by the core stack later.
Same for the "in-place" recycling, i.e. when an unused buffer gets
assigned to a first needs-refilling descriptor. In some cases, this
was leading to moving up to 63 &iavf_rx_buf structures around the ring
on a per-field basis -- not something wanted on hotpath.
The change allows to greatly simplify certain parts of the code:

Function: add/remove: 0/2 grow/shrink: 0/7 up/down: 0/-744 (-744)

Although the array of &iavf_rx_buf is barely used now and could be
replaced with just page pointer array, don't touch it now to not
complicate replacing it with libie Rx buffer struct later on.
No surprise perf loses up to 30% here, but that regression will
go away once PP lands.
Note that iavf_rx_pg_*() definitions are left to reduce diffstat.
They will be removed with the conversion to Page Pool.

Signed-off-by: Alexander Lobakin <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

1 files changed, 1 insertions, 23 deletions

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 5eb7379956e4..ffb71a62b105 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -715,32 +715,10 @@ static void iavf_configure_tx(struct iavf_adapter *adapter)
  **/
 static void iavf_configure_rx(struct iavf_adapter *adapter)
 {
-	unsigned int rx_buf_len = IAVF_RXBUFFER_2048;
 	struct iavf_hw *hw = &adapter->hw;
-	int i;
-
-	if (PAGE_SIZE < 8192) {
-		struct net_device *netdev = adapter->netdev;
 
-		/* For jumbo frames on systems with 4K pages we have to use
-		 * an order 1 page, so we might as well increase the size
-		 * of our Rx buffer to make better use of the available space
-		 */
-		rx_buf_len = IAVF_RXBUFFER_3072;
-
-		/* We use a 1536 buffer size for configurations with
-		 * standard Ethernet mtu.  On x86 this gives us enough room
-		 * for shared info and 192 bytes of padding.
-		 */
-		if (!IAVF_2K_TOO_SMALL_WITH_PADDING &&
-		    (netdev->mtu <= ETH_DATA_LEN))
-			rx_buf_len = IAVF_RXBUFFER_1536 - NET_IP_ALIGN;
-	}
-
-	for (i = 0; i < adapter->num_active_queues; i++) {
+	for (u32 i = 0; i < adapter->num_active_queues; i++)
 		adapter->rx_rings[i].tail = hw->hw_addr + IAVF_QRX_TAIL1(i);
-		adapter->rx_rings[i].rx_buf_len = rx_buf_len;
-	}
 }
 
 /**