amd-xgbe: Simplify the Rx desciptor ring tracking
authorLendacky, Thomas <Thomas.Lendacky@amd.com>
Fri, 16 Jan 2015 18:46:50 +0000 (12:46 -0600)
committerDavid S. Miller <davem@davemloft.net>
Sat, 17 Jan 2015 03:24:20 +0000 (22:24 -0500)
Make the Rx descriptor ring processing similar to the Tx descriptor
ring processing.  Remove the realloc_index and realloc_threshold
variables and base everything on the current index counter and the
dirty index counter.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/amd/xgbe/xgbe-desc.c
drivers/net/ethernet/amd/xgbe/xgbe-drv.c
drivers/net/ethernet/amd/xgbe/xgbe.h

index a50891f521978ff67d55959fbfab1b63da762f4c..d81fc6bd4759064f72d716e3cd81f0045f8d1bc9 100644 (file)
@@ -422,7 +422,6 @@ static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
 
                ring->cur = 0;
                ring->dirty = 0;
-               memset(&ring->rx, 0, sizeof(ring->rx));
 
                hw_if->rx_desc_init(channel);
        }
@@ -621,35 +620,6 @@ err_out:
        return 0;
 }
 
-static void xgbe_realloc_rx_buffer(struct xgbe_channel *channel)
-{
-       struct xgbe_prv_data *pdata = channel->pdata;
-       struct xgbe_hw_if *hw_if = &pdata->hw_if;
-       struct xgbe_ring *ring = channel->rx_ring;
-       struct xgbe_ring_data *rdata;
-       int i;
-
-       DBGPR("-->xgbe_realloc_rx_buffer: rx_ring->rx.realloc_index = %u\n",
-             ring->rx.realloc_index);
-
-       for (i = 0; i < ring->dirty; i++) {
-               rdata = XGBE_GET_DESC_DATA(ring, ring->rx.realloc_index);
-
-               /* Reset rdata values */
-               xgbe_unmap_rdata(pdata, rdata);
-
-               if (xgbe_map_rx_buffer(pdata, ring, rdata))
-                       break;
-
-               hw_if->rx_desc_reset(rdata);
-
-               ring->rx.realloc_index++;
-       }
-       ring->dirty = 0;
-
-       DBGPR("<--xgbe_realloc_rx_buffer\n");
-}
-
 void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
 {
        DBGPR("-->xgbe_init_function_ptrs_desc\n");
@@ -657,7 +627,7 @@ void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
        desc_if->alloc_ring_resources = xgbe_alloc_ring_resources;
        desc_if->free_ring_resources = xgbe_free_ring_resources;
        desc_if->map_tx_skb = xgbe_map_tx_skb;
-       desc_if->realloc_rx_buffer = xgbe_realloc_rx_buffer;
+       desc_if->map_rx_buffer = xgbe_map_rx_buffer;
        desc_if->unmap_rdata = xgbe_unmap_rdata;
        desc_if->wrapper_tx_desc_init = xgbe_wrapper_tx_descriptor_init;
        desc_if->wrapper_rx_desc_init = xgbe_wrapper_rx_descriptor_init;
index bdb373c87050c555df40899f9bcfefc99865cea5..e2f560ff510430eb39edbd06a597f6de4d2fe554 100644 (file)
@@ -225,6 +225,11 @@ static inline unsigned int xgbe_tx_avail_desc(struct xgbe_ring *ring)
        return (ring->rdesc_count - (ring->cur - ring->dirty));
 }
 
+static inline unsigned int xgbe_rx_dirty_desc(struct xgbe_ring *ring)
+{
+       return (ring->cur - ring->dirty);
+}
+
 static int xgbe_maybe_stop_tx_queue(struct xgbe_channel *channel,
                                    struct xgbe_ring *ring, unsigned int count)
 {
@@ -1775,15 +1780,28 @@ struct net_device_ops *xgbe_get_netdev_ops(void)
 static void xgbe_rx_refresh(struct xgbe_channel *channel)
 {
        struct xgbe_prv_data *pdata = channel->pdata;
+       struct xgbe_hw_if *hw_if = &pdata->hw_if;
        struct xgbe_desc_if *desc_if = &pdata->desc_if;
        struct xgbe_ring *ring = channel->rx_ring;
        struct xgbe_ring_data *rdata;
 
-       desc_if->realloc_rx_buffer(channel);
+       while (ring->dirty != ring->cur) {
+               rdata = XGBE_GET_DESC_DATA(ring, ring->dirty);
+
+               /* Reset rdata values */
+               desc_if->unmap_rdata(pdata, rdata);
+
+               if (desc_if->map_rx_buffer(pdata, ring, rdata))
+                       break;
+
+               hw_if->rx_desc_reset(rdata);
+
+               ring->dirty++;
+       }
 
        /* Update the Rx Tail Pointer Register with address of
         * the last cleaned entry */
-       rdata = XGBE_GET_DESC_DATA(ring, ring->rx.realloc_index - 1);
+       rdata = XGBE_GET_DESC_DATA(ring, ring->dirty - 1);
        XGMAC_DMA_IOWRITE(channel, DMA_CH_RDTR_LO,
                          lower_32_bits(rdata->rdesc_dma));
 }
@@ -1933,7 +1951,7 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget)
 read_again:
                rdata = XGBE_GET_DESC_DATA(ring, ring->cur);
 
-               if (ring->dirty > (XGBE_RX_DESC_CNT >> 3))
+               if (xgbe_rx_dirty_desc(ring) > (XGBE_RX_DESC_CNT >> 3))
                        xgbe_rx_refresh(channel);
 
                if (hw_if->dev_read(channel))
@@ -1941,7 +1959,6 @@ read_again:
 
                received++;
                ring->cur++;
-               ring->dirty++;
 
                incomplete = XGMAC_GET_BITS(packet->attributes,
                                            RX_PACKET_ATTRIBUTES,
index 2af6affc35a7c7ac322a62fb692d6ec4e49edd03..e6ee64e1d6ec87262ea759edf1b0b70206284428 100644 (file)
@@ -361,8 +361,7 @@ struct xgbe_ring {
         *  cur   - Tx: index of descriptor to be used for current transfer
         *          Rx: index of descriptor to check for packet availability
         *  dirty - Tx: index of descriptor to check for transfer complete
-        *          Rx: count of descriptors in which a packet has been received
-        *              (used with skb_realloc_index to refresh the ring)
+        *          Rx: index of descriptor to check for buffer reallocation
         */
        unsigned int cur;
        unsigned int dirty;
@@ -377,11 +376,6 @@ struct xgbe_ring {
                        unsigned short cur_mss;
                        unsigned short cur_vlan_ctag;
                } tx;
-
-               struct {
-                       unsigned int realloc_index;
-                       unsigned int realloc_threshold;
-               } rx;
        };
 } ____cacheline_aligned;
 
@@ -596,7 +590,8 @@ struct xgbe_desc_if {
        int (*alloc_ring_resources)(struct xgbe_prv_data *);
        void (*free_ring_resources)(struct xgbe_prv_data *);
        int (*map_tx_skb)(struct xgbe_channel *, struct sk_buff *);
-       void (*realloc_rx_buffer)(struct xgbe_channel *);
+       int (*map_rx_buffer)(struct xgbe_prv_data *, struct xgbe_ring *,
+                            struct xgbe_ring_data *);
        void (*unmap_rdata)(struct xgbe_prv_data *, struct xgbe_ring_data *);
        void (*wrapper_tx_desc_init)(struct xgbe_prv_data *);
        void (*wrapper_rx_desc_init)(struct xgbe_prv_data *);