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 <fabrice.gasnier@st.com>
Signed-off-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>
This commit is contained in:
Giuseppe Cavallaro 2016-02-29 14:27:33 +01:00 committed by David S. Miller
parent 2a6d8e1726
commit 96951366ce
4 changed files with 14 additions and 2 deletions

View File

@ -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; struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr;
unsigned int entry = priv->dirty_tx; 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 /* NOTE: Device will overwrite des3 with timestamp value if
* 1588-2002 time stamping is enabled, hence reinitialize it * 1588-2002 time stamping is enabled, hence reinitialize it
* to keep explicit chaining in the descriptor. * to keep explicit chaining in the descriptor.

View File

@ -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].buf = desc->des2;
priv->tx_skbuff_dma[entry].len = bmax; priv->tx_skbuff_dma[entry].len = bmax;
priv->tx_skbuff_dma[entry].is_jumbo = true;
desc->des3 = desc->des2 + BUF_SIZE_4KiB; desc->des3 = desc->des2 + BUF_SIZE_4KiB;
priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, 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; return -1;
priv->tx_skbuff_dma[entry].buf = desc->des2; priv->tx_skbuff_dma[entry].buf = desc->des2;
priv->tx_skbuff_dma[entry].len = len; priv->tx_skbuff_dma[entry].len = len;
priv->tx_skbuff_dma[entry].is_jumbo = true;
desc->des3 = desc->des2 + BUF_SIZE_4KiB; desc->des3 = desc->des2 + BUF_SIZE_4KiB;
priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, 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; return -1;
priv->tx_skbuff_dma[entry].buf = desc->des2; priv->tx_skbuff_dma[entry].buf = desc->des2;
priv->tx_skbuff_dma[entry].len = nopaged_len; priv->tx_skbuff_dma[entry].len = nopaged_len;
priv->tx_skbuff_dma[entry].is_jumbo = true;
desc->des3 = desc->des2 + BUF_SIZE_4KiB; desc->des3 = desc->des2 + BUF_SIZE_4KiB;
priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum, priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum,
STMMAC_RING_MODE); 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) 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; p->des3 = 0;
} }

View File

@ -47,6 +47,7 @@ struct stmmac_tx_info {
bool map_as_page; bool map_as_page;
unsigned len; unsigned len;
bool last_segment; bool last_segment;
bool is_jumbo;
}; };
struct stmmac_priv { struct stmmac_priv {

View File

@ -1361,6 +1361,7 @@ static void stmmac_tx_clean(struct stmmac_priv *priv)
} }
priv->hw->mode->clean_desc3(priv, p); priv->hw->mode->clean_desc3(priv, p);
priv->tx_skbuff_dma[entry].last_segment = false; priv->tx_skbuff_dma[entry].last_segment = false;
priv->tx_skbuff_dma[entry].is_jumbo = false;
if (likely(skb != NULL)) { if (likely(skb != NULL)) {
pkts_compl++; pkts_compl++;