10 Apr
2024
10 Apr
'24
3:02 p.m.
On Wed, 10 Apr 2024 16:02:00 +0200 Julien Panis wrote:
You shouldn't build the skb upfront any more. Give the page to the HW, once HW sends you a completion - build the skbs. If build fails (allocation failure) just give the page back to HW. If it succeeds, however, you'll get a skb which is far more likely to be cache hot.
Not sure I get this point.
"Give the page to the HW" = Do you mean that I should dma_map_single() a full page (|PAGE_SIZE|) in am65_cpsw_nuss_rx_push() ?
Yes, I think so. I think that's what you effectively do now anyway, you just limit the len and wrap it in an skb. But am65_cpsw_nuss_rx_push() will effectively get that page back from skb->data and map it.