stmmac: optimize tx clean function
This patch "inline" get_tx_owner and get_ls routines. It Results in a
unique read to tdes0, instead of three, to check TX_OWN and LS bits,
and other status bits.
It helps improve driver TX path by removing two uncached read/writes
inside TX clean loop for enhanced descriptors but not for normal ones
because the des1 must be read in any case.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 24c3608..d31179f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1313,32 +1313,31 @@
priv->xstats.tx_clean++;
while (entry != priv->cur_tx) {
- int last;
struct sk_buff *skb = priv->tx_skbuff[entry];
struct dma_desc *p;
+ int status;
if (priv->extend_desc)
p = (struct dma_desc *)(priv->dma_etx + entry);
else
p = priv->dma_tx + entry;
- /* Check if the descriptor is owned by the DMA. */
- if (priv->hw->desc->get_tx_owner(p))
- break;
-
- /* Verify tx error by looking at the last segment. */
- last = priv->tx_skbuff_dma[entry].last_segment;
- if (likely(last)) {
- int tx_error =
- priv->hw->desc->tx_status(&priv->dev->stats,
+ status = priv->hw->desc->tx_status(&priv->dev->stats,
&priv->xstats, p,
priv->ioaddr);
- if (likely(tx_error == 0)) {
+ /* Check if the descriptor is owned by the DMA */
+ if (unlikely(status & tx_dma_own))
+ break;
+
+ /* Just consider the last segment and ...*/
+ if (likely(!(status & tx_not_ls))) {
+ /* ... verify the status error condition */
+ if (unlikely(status & tx_err)) {
+ priv->dev->stats.tx_errors++;
+ } else {
priv->dev->stats.tx_packets++;
priv->xstats.tx_pkt_n++;
- } else
- priv->dev->stats.tx_errors++;
-
+ }
stmmac_get_tx_hwtstamp(priv, entry, skb);
}
if (netif_msg_tx_done(priv))