tsnep: Improve TX length handling

TX length can by calculated more efficient during map and unmap of
fragments. Another reason is that, by moving TX statistic counting to
tsnep_tx_poll() it can be used there for XDP too.

Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c
index 7fe6a89..9f8ca6d 100644 (file)
--- a/drivers/net/ethernet/engleder/tsnep_main.c
+++ b/drivers/net/ethernet/engleder/tsnep_main.c
@@ -262,14 +262,14 @@ alloc_failed:
        return retval;
 }
 
-static void tsnep_tx_activate(struct tsnep_tx *tx, int index, bool last)
+static void tsnep_tx_activate(struct tsnep_tx *tx, int index, int length,
+                             bool last)
 {
        struct tsnep_tx_entry *entry = &tx->entry[index];
 
        entry->properties = 0;
        if (entry->skb) {
-               entry->properties =
-                       skb_pagelen(entry->skb) & TSNEP_DESC_LENGTH_MASK;
+               entry->properties = length & TSNEP_DESC_LENGTH_MASK;
                entry->properties |= TSNEP_DESC_INTERRUPT_FLAG;
                if (skb_shinfo(entry->skb)->tx_flags & SKBTX_IN_PROGRESS)
                        entry->properties |= TSNEP_DESC_EXTENDED_WRITEBACK_FLAG;
@@ -334,6 +334,7 @@ static int tsnep_tx_map(struct sk_buff *skb, struct tsnep_tx *tx, int count)
        struct tsnep_tx_entry *entry;
        unsigned int len;
        dma_addr_t dma;
+       int map_len = 0;
        int i;
 
        for (i = 0; i < count; i++) {
@@ -356,15 +357,18 @@ static int tsnep_tx_map(struct sk_buff *skb, struct tsnep_tx *tx, int count)
                dma_unmap_addr_set(entry, dma, dma);
 
                entry->desc->tx = __cpu_to_le64(dma);
+
+               map_len += len;
        }
 
-       return 0;
+       return map_len;
 }
 
-static void tsnep_tx_unmap(struct tsnep_tx *tx, int index, int count)
+static int tsnep_tx_unmap(struct tsnep_tx *tx, int index, int count)
 {
        struct device *dmadev = tx->adapter->dmadev;
        struct tsnep_tx_entry *entry;
+       int map_len = 0;
        int i;
 
        for (i = 0; i < count; i++) {
@@ -381,9 +385,12 @@ static void tsnep_tx_unmap(struct tsnep_tx *tx, int index, int count)
                                               dma_unmap_addr(entry, dma),
                                               dma_unmap_len(entry, len),
                                               DMA_TO_DEVICE);
+                       map_len += entry->len;
                        entry->len = 0;
                }
        }
+
+       return map_len;
 }
 
 static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
@@ -392,6 +399,7 @@ static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
        unsigned long flags;
        int count = 1;
        struct tsnep_tx_entry *entry;
+       int length;
        int i;
        int retval;
 
@@ -415,7 +423,7 @@ static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
        entry->skb = skb;
 
        retval = tsnep_tx_map(skb, tx, count);
-       if (retval != 0) {
+       if (retval < 0) {
                tsnep_tx_unmap(tx, tx->write, count);
                dev_kfree_skb_any(entry->skb);
                entry->skb = NULL;
@@ -428,12 +436,13 @@ static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
 
                return NETDEV_TX_OK;
        }
+       length = retval;
 
        if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)
                skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
 
        for (i = 0; i < count; i++)
-               tsnep_tx_activate(tx, (tx->write + i) % TSNEP_RING_SIZE,
+               tsnep_tx_activate(tx, (tx->write + i) % TSNEP_RING_SIZE, length,
                                  i == (count - 1));
        tx->write = (tx->write + count) % TSNEP_RING_SIZE;
 
@@ -449,9 +458,6 @@ static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
                netif_stop_queue(tx->adapter->netdev);
        }
 
-       tx->packets++;
-       tx->bytes += skb_pagelen(entry->skb) + ETH_FCS_LEN;
-
        spin_unlock_irqrestore(&tx->lock, flags);
 
        return NETDEV_TX_OK;
@@ -463,6 +469,7 @@ static bool tsnep_tx_poll(struct tsnep_tx *tx, int napi_budget)
        int budget = 128;
        struct tsnep_tx_entry *entry;
        int count;
+       int length;
 
        spin_lock_irqsave(&tx->lock, flags);
 
@@ -485,7 +492,7 @@ static bool tsnep_tx_poll(struct tsnep_tx *tx, int napi_budget)
                if (skb_shinfo(entry->skb)->nr_frags > 0)
                        count += skb_shinfo(entry->skb)->nr_frags;
 
-               tsnep_tx_unmap(tx, tx->read, count);
+               length = tsnep_tx_unmap(tx, tx->read, count);
 
                if ((skb_shinfo(entry->skb)->tx_flags & SKBTX_IN_PROGRESS) &&
                    (__le32_to_cpu(entry->desc_wb->properties) &
@@ -512,6 +519,9 @@ static bool tsnep_tx_poll(struct tsnep_tx *tx, int napi_budget)
 
                tx->read = (tx->read + count) % TSNEP_RING_SIZE;
 
+               tx->packets++;
+               tx->bytes += length + ETH_FCS_LEN;
+
                budget--;
        } while (likely(budget));