---

yaml --- r: 376090 b: refs/heads/master c: 950c54d h: refs/heads/master v: v3
git-mirror · May 14, 2013 · 3c9e170 · 3c9e170
1 parent 5898246
commit 3c9e170
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Showing 4 changed files with 20 additions and 6 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c14ff2ea2d5818c811e5c6e67e794df4a71a6094
+refs/heads/master: 950c54df1e503ece4e2987b0cf6e2e4e22817c0c
diff --git a/trunk/drivers/net/ethernet/sfc/efx.c b/trunk/drivers/net/ethernet/sfc/efx.c
@@ -643,9 +643,11 @@ static void efx_start_datapath(struct efx_nic *efx)
 		efx->rx_scatter = false;
 		efx->rx_buffer_order = 0;
 	} else if (efx->type->can_rx_scatter) {
+		BUILD_BUG_ON(EFX_RX_USR_BUF_SIZE % L1_CACHE_BYTES);
 		BUILD_BUG_ON(sizeof(struct efx_rx_page_state) +
-			     NET_IP_ALIGN + EFX_RX_USR_BUF_SIZE >
-			     PAGE_SIZE / 2);
+			     2 * ALIGN(NET_IP_ALIGN + EFX_RX_USR_BUF_SIZE,
+				       EFX_RX_BUF_ALIGNMENT) >
+			     PAGE_SIZE);
 		efx->rx_scatter = true;
 		efx->rx_dma_len = EFX_RX_USR_BUF_SIZE;
 		efx->rx_buffer_order = 0;

diff --git a/trunk/drivers/net/ethernet/sfc/net_driver.h b/trunk/drivers/net/ethernet/sfc/net_driver.h
@@ -72,8 +72,20 @@
 /* Maximum possible MTU the driver supports */
 #define EFX_MAX_MTU (9 * 1024)
 
-/* Size of an RX scatter buffer.  Small enough to pack 2 into a 4K page. */
-#define EFX_RX_USR_BUF_SIZE 1824
+/* Size of an RX scatter buffer.  Small enough to pack 2 into a 4K page,
+ * and should be a multiple of the cache line size.
+ */
+#define EFX_RX_USR_BUF_SIZE	(2048 - 256)
+
+/* If possible, we should ensure cache line alignment at start and end
+ * of every buffer.  Otherwise, we just need to ensure 4-byte
+ * alignment of the network header.
+ */
+#if NET_IP_ALIGN == 0
+#define EFX_RX_BUF_ALIGNMENT	L1_CACHE_BYTES
+#else
+#define EFX_RX_BUF_ALIGNMENT	4
+#endif
 
 /* Forward declare Precision Time Protocol (PTP) support structure. */
 struct efx_ptp_data;

diff --git a/trunk/drivers/net/ethernet/sfc/rx.c b/trunk/drivers/net/ethernet/sfc/rx.c
@@ -94,7 +94,7 @@ static inline void efx_sync_rx_buffer(struct efx_nic *efx,
 void efx_rx_config_page_split(struct efx_nic *efx)
 {
 	efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + NET_IP_ALIGN,
-				      L1_CACHE_BYTES);
+				      EFX_RX_BUF_ALIGNMENT);
 	efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
 		((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /
 		 efx->rx_page_buf_step);