[PATCH v3 06/17] stmmac: add last_segment field to dma data
From: Alexandre TORGUE <hidden>
Date: 2016-02-29 13:28:55
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Giuseppe Cavallaro <redacted> last_segment field is read twice from dma descriptors in stmmac_clean(). Add last_segment to dma data so that this flag is from priv structure in cache instead of memory. It avoids reading twice from memory for each loop in stmmac_clean(). Signed-off-by: Fabrice Gasnier <redacted> Signed-off-by: Giuseppe Cavallaro <redacted> Signed-off-by: Alexandre TORGUE <redacted>
diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c
index 7fa7ab0d..355eafb 100644
--- a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c
+++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c@@ -150,8 +150,9 @@ static void stmmac_refill_desc3(void *priv_ptr, struct dma_desc *p) static void stmmac_clean_desc3(void *priv_ptr, struct dma_desc *p) { struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr; + unsigned int entry = priv->dirty_tx; - if (priv->hw->desc->get_tx_ls(p) && !priv->extend_desc) + if (priv->tx_skbuff_dma[entry].last_segment && !priv->extend_desc) /* NOTE: Device will overwrite des3 with timestamp value if * 1588-2002 time stamping is enabled, hence reinitialize it * to keep explicit chaining in the descriptor.
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index c497460..0436918 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h@@ -46,6 +46,7 @@ struct stmmac_tx_info { dma_addr_t buf; bool map_as_page; unsigned len; + bool last_segment; }; struct stmmac_priv {
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 90a946f..feae0de 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -1094,6 +1094,7 @@ static int init_dma_desc_rings(struct net_device *dev, gfp_t flags) priv->tx_skbuff_dma[i].buf = 0; priv->tx_skbuff_dma[i].map_as_page = false; priv->tx_skbuff_dma[i].len = 0; + priv->tx_skbuff_dma[i].last_segment = false; priv->tx_skbuff[i] = NULL; }
@@ -1326,7 +1327,7 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) break; /* Verify tx error by looking at the last segment. */ - last = priv->hw->desc->get_tx_ls(p); + last = priv->tx_skbuff_dma[entry].last_segment; if (likely(last)) { int tx_error = priv->hw->desc->tx_status(&priv->dev->stats,
@@ -1359,6 +1360,7 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) priv->tx_skbuff_dma[entry].map_as_page = false; } priv->hw->mode->clean_desc3(priv, p); + priv->tx_skbuff_dma[entry].last_segment = false; if (likely(skb != NULL)) { pkts_compl++;
@@ -2028,6 +2030,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) /* Finalize the latest segment. */ priv->hw->desc->close_tx_desc(desc); + priv->tx_skbuff_dma[entry].last_segment = true; wmb(); /* According to the coalesce parameter the IC bit for the latest
--
1.9.1