From 96951366ce8546662de56f58a3885b94326f9670 Mon Sep 17 00:00:00 2001 From: Giuseppe Cavallaro Date: Mon, 29 Feb 2016 14:27:33 +0100 Subject: [PATCH] stmmac: add is_jumbo field to dma data Optimize tx_clean by avoiding a des3 read in stmmac_clean_desc3(). In ring mode, TX, des3 seems only used when xmit a jumbo frame. In case of normal descriptors, it may also be used for time stamping. Clean it in the above two case, without reading it. Signed-off-by: Fabrice Gasnier Signed-off-by: Giuseppe Cavallaro Signed-off-by: Alexandre TORGUE Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/chain_mode.c | 3 ++- drivers/net/ethernet/stmicro/stmmac/ring_mode.c | 11 ++++++++++- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 1 + drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 1 + 4 files changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c index 355eafb5d6c7..dacb6542c6dd 100644 --- a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c +++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c @@ -152,7 +152,8 @@ 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->tx_skbuff_dma[entry].last_segment && !priv->extend_desc) + if (priv->tx_skbuff_dma[entry].last_segment && !priv->extend_desc && + priv->hwts_tx_en) /* 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/ring_mode.c b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c index cfc2f24ba08b..c6487746b235 100644 --- a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c +++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c @@ -57,6 +57,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) priv->tx_skbuff_dma[entry].buf = desc->des2; priv->tx_skbuff_dma[entry].len = bmax; + priv->tx_skbuff_dma[entry].is_jumbo = true; desc->des3 = desc->des2 + BUF_SIZE_4KiB; priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, @@ -76,6 +77,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) return -1; priv->tx_skbuff_dma[entry].buf = desc->des2; priv->tx_skbuff_dma[entry].len = len; + priv->tx_skbuff_dma[entry].is_jumbo = true; desc->des3 = desc->des2 + BUF_SIZE_4KiB; priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, @@ -89,6 +91,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) return -1; priv->tx_skbuff_dma[entry].buf = desc->des2; priv->tx_skbuff_dma[entry].len = nopaged_len; + priv->tx_skbuff_dma[entry].is_jumbo = true; desc->des3 = desc->des2 + BUF_SIZE_4KiB; priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum, STMMAC_RING_MODE); @@ -126,7 +129,13 @@ static void stmmac_init_desc3(struct dma_desc *p) static void stmmac_clean_desc3(void *priv_ptr, struct dma_desc *p) { - if (unlikely(p->des3)) + struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr; + unsigned int entry = priv->dirty_tx; + + /* des3 is only used for jumbo frames tx or time stamping */ + if (unlikely(priv->tx_skbuff_dma[entry].is_jumbo || + (priv->tx_skbuff_dma[entry].last_segment && + !priv->extend_desc && priv->hwts_tx_en))) p->des3 = 0; } diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h index 043691852c26..0d01f3ea4cc8 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h @@ -47,6 +47,7 @@ struct stmmac_tx_info { bool map_as_page; unsigned len; bool last_segment; + bool is_jumbo; }; struct stmmac_priv { diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index feae0dec1f43..0194a8f26f8c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1361,6 +1361,7 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) } priv->hw->mode->clean_desc3(priv, p); priv->tx_skbuff_dma[entry].last_segment = false; + priv->tx_skbuff_dma[entry].is_jumbo = false; if (likely(skb != NULL)) { pkts_compl++;