Re: [PATCH net-next 0/8] net: macb: Add XDP support and page pool integration
From: Théo Lebrun <theo.lebrun@bootlin.com>
Date: 2026-02-20 15:58:22
On Thu Feb 19, 2026 at 7:05 PM CET, Paolo Valerio wrote:
On 16 Feb 2026 at 10:17:39 AM, Théo Lebrun [off-list ref] wrote:quoted
On Sat Feb 14, 2026 at 4:37 PM CET, Paolo Valerio wrote:quoted
On 13 Feb 2026 at 05:57:17 PM, Théo Lebrun [off-list ref] wrote: The one about DMA_BIDIRECTIONAL is already part of this review cycle (see bot's reply to 5/8) and already incorporated. I'm also considering the possibility a change that make this no longer relevant anyways, but I'm not sure as it was planned as a follow up.Yes indeed, Jakub's LLM pointed it out. I looked into this for a bit and couldn't find any good solution. In the end I couldn't find any measurable performance improvement so no need to worry about it (on my platform). I guess the only valid option is to reopen if `running && (!!old_prog != !!new_prog)`?yeah, which I guess is fine, after all. Also, this way at some point we may even consider to remove the xdp headroom for the skb case and reserve less like NET_SKB_PAD. This would have the extra bonus to not require a full page for 1500 mtu with 4k pages.
I will be adding a close/open cycle with the XSK pool introduction. That is why in my branch I preferred to lean in the direction of not closing/reopening in the XDP program load (to avoid 2x reopens on AF_XDP zero-copy). I get your point though. Thanks, -- Théo Lebrun, Bootlin Embedded Linux and Kernel engineering https://bootlin.com