Stephen Hemminger wrote:
On Tue, 9 Jan 2007 09:42:03 +0100
Ingo Oeser <[EMAIL PROTECTED]> wrote:
Hi Stephen,
Stephen Hemminger schrieb:
--- netdev-2.6.orig/drivers/net/chelsio/sge.c
+++ netdev-2.6/drivers/net/chelsio/sge.c
[...]
@@ -1043,45 +1046,42 @@ static void recycle_fl_buf(struct freelQ
* be copied but there is no memory for the copy.
*/
static inline struct sk_buff *get_packet(struct pci_dev *pdev,
- struct freelQ *fl, unsigned int len,
- int dma_pad, int skb_pad,
- unsigned int copy_thres,
- unsigned int drop_thres)
+ struct freelQ *fl, unsigned int len)
{
struct sk_buff *skb;
- struct freelQ_ce *ce = &fl->centries[fl->cidx];
+ const struct freelQ_ce *ce = &fl->centries[fl->cidx];
- if (len < copy_thres) {
- skb = alloc_skb(len + skb_pad, GFP_ATOMIC);
- if (likely(skb != NULL)) {
- skb_reserve(skb, skb_pad);
- skb_put(skb, len);
- pci_dma_sync_single_for_cpu(pdev,
- pci_unmap_addr(ce, dma_addr),
- pci_unmap_len(ce, dma_len),
- PCI_DMA_FROMDEVICE);
- memcpy(skb->data, ce->skb->data + dma_pad, len);
- pci_dma_sync_single_for_device(pdev,
+ if (len < copybreak) {
+ skb = alloc_skb(len + 2, GFP_ATOMIC);
+ if (!skb)
+ goto use_orig_buf;
+
+ skb_reserve(skb, 2); /* align IP header */
Please use NET_IP_ALIGN here:
Wrong, NET_IP_ALIGN is intended to deal with platforms where alignment of DMA
is more
important of alignment of structures. Therefore if data is copied, it should
always be 2.
+ skb = alloc_skb(len + NET_IP_ALIGN, GFP_ATOMIC);
+ if (!skb)
+ goto use_orig_buf;
+
+ skb_reserve(skb, NET_IP_ALIGN);
+ skb_put(skb, len);
+ pci_dma_sync_single_for_cpu(pdev,
pci_unmap_addr(ce, dma_addr),
pci_unmap_len(ce, dma_len),
PCI_DMA_FROMDEVICE);
- } else if (!drop_thres)
- goto use_orig_buf;
-
+ memcpy(skb->data, ce->skb->data, len);
+ pci_dma_sync_single_for_device(pdev,
+ pci_unmap_addr(ce, dma_addr),
+ pci_unmap_len(ce, dma_len),
+ PCI_DMA_FROMDEVICE);
recycle_fl_buf(fl, fl->cidx);
return skb;
}
- if (fl->credits < drop_thres) {
+use_orig_buf:
+ if (fl->credits < 2) {
Why 2? What does this magic number mean?
No idea, it was there in the original. (as a parameter).
The T2 HW behaves nicely when it is guaranteed to have 2 available
entries in the rx free list.
Cheers,
Divy
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
