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| author | Michael Chan <mchan@broadcom.com> | 2010-05-06 08:58:13 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-05-06 22:17:24 -0700 |
| commit | a33fa66bcf365ffe5b79d1ae1d3582cc261ae56e (patch) | |
| tree | cf714757a5c3644bd8154a4da0cea4eb53a80032 | |
| parent | c67938a9e071fa51c91ed17a14382e128368d115 (diff) | |
| download | linux-3.10-a33fa66bcf365ffe5b79d1ae1d3582cc261ae56e.tar.gz linux-3.10-a33fa66bcf365ffe5b79d1ae1d3582cc261ae56e.tar.bz2 linux-3.10-a33fa66bcf365ffe5b79d1ae1d3582cc261ae56e.zip | |
bnx2: Add prefetches to rx path.
Add prefetches of the skb and the next rx descriptor to speed up rx path.
Use prefetchw() for the skb [suggested by Eric Dumazet].
The rx descriptor is in skb->data which is mapped for streaming mode DMA.
Eric Dumazet pointed out that we should not prefetch the data before
dma_sync. So we prefetch only if dma_sync is no_op on the system.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/bnx2.c | 16 | ||||
| -rw-r--r-- | drivers/net/bnx2.h | 1 |
2 files changed, 14 insertions, 3 deletions
diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c index 320526b9b46..667f4196dc2 100644 --- a/drivers/net/bnx2.c +++ b/drivers/net/bnx2.c @@ -2719,6 +2719,7 @@ bnx2_alloc_rx_skb(struct bnx2 *bp, struct bnx2_rx_ring_info *rxr, u16 index) } rx_buf->skb = skb; + rx_buf->desc = (struct l2_fhdr *) skb->data; dma_unmap_addr_set(rx_buf, mapping, mapping); rxbd->rx_bd_haddr_hi = (u64) mapping >> 32; @@ -2941,6 +2942,7 @@ bnx2_reuse_rx_skb(struct bnx2 *bp, struct bnx2_rx_ring_info *rxr, rxr->rx_prod_bseq += bp->rx_buf_use_size; prod_rx_buf->skb = skb; + prod_rx_buf->desc = (struct l2_fhdr *) skb->data; if (cons == prod) return; @@ -3074,6 +3076,7 @@ bnx2_rx_int(struct bnx2 *bp, struct bnx2_napi *bnapi, int budget) u16 hw_cons, sw_cons, sw_ring_cons, sw_prod, sw_ring_prod; struct l2_fhdr *rx_hdr; int rx_pkt = 0, pg_ring_used = 0; + struct pci_dev *pdev = bp->pdev; hw_cons = bnx2_get_hw_rx_cons(bnapi); sw_cons = rxr->rx_cons; @@ -3086,7 +3089,7 @@ bnx2_rx_int(struct bnx2 *bp, struct bnx2_napi *bnapi, int budget) while (sw_cons != hw_cons) { unsigned int len, hdr_len; u32 status; - struct sw_bd *rx_buf; + struct sw_bd *rx_buf, *next_rx_buf; struct sk_buff *skb; dma_addr_t dma_addr; u16 vtag = 0; @@ -3097,7 +3100,14 @@ bnx2_rx_int(struct bnx2 *bp, struct bnx2_napi *bnapi, int budget) rx_buf = &rxr->rx_buf_ring[sw_ring_cons]; skb = rx_buf->skb; + prefetchw(skb); + if (!get_dma_ops(&pdev->dev)->sync_single_for_cpu) { + next_rx_buf = + &rxr->rx_buf_ring[ + RX_RING_IDX(NEXT_RX_BD(sw_cons))]; + prefetch(next_rx_buf->desc); + } rx_buf->skb = NULL; dma_addr = dma_unmap_addr(rx_buf, mapping); @@ -3106,7 +3116,7 @@ bnx2_rx_int(struct bnx2 *bp, struct bnx2_napi *bnapi, int budget) BNX2_RX_OFFSET + BNX2_RX_COPY_THRESH, PCI_DMA_FROMDEVICE); - rx_hdr = (struct l2_fhdr *) skb->data; + rx_hdr = rx_buf->desc; len = rx_hdr->l2_fhdr_pkt_len; status = rx_hdr->l2_fhdr_status; @@ -5764,7 +5774,7 @@ bnx2_run_loopback(struct bnx2 *bp, int loopback_mode) rx_buf = &rxr->rx_buf_ring[rx_start_idx]; rx_skb = rx_buf->skb; - rx_hdr = (struct l2_fhdr *) rx_skb->data; + rx_hdr = rx_buf->desc; skb_reserve(rx_skb, BNX2_RX_OFFSET); pci_dma_sync_single_for_cpu(bp->pdev, diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h index ab34a5d86f8..dd35bd0b7e0 100644 --- a/drivers/net/bnx2.h +++ b/drivers/net/bnx2.h @@ -6551,6 +6551,7 @@ struct l2_fhdr { struct sw_bd { struct sk_buff *skb; + struct l2_fhdr *desc; DEFINE_DMA_UNMAP_ADDR(mapping); }; |