Re: [PATCH net v1] net: stmmac: set PP_FLAG_DMA_SYNC_DEV only if XDP is enabled

[Paolo Abeni]

On 9/13/24 13:02, Furong Xu wrote:
> When XDP is not enabled, the page which holds the received buffer
> will be recycled once the buffer is copied into SKB by
> skb_copy_to_linear_data(), then the MAC core will never reuse this
> page any longer. Set PP_FLAG_DMA_SYNC_DEV wastes CPU cycles.
>
> This patch brings up to 9% noticeable performance improvement on
> certain platforms.
>
> Fixes: 5fabb01207a2 ("net: stmmac: Add initial XDP support")
> Signed-off-by: Furong Xu <0x1207@xxxxxxxxx>

I'm quite unconvinced that every performance improvement would be 
eligible to be considered a fix.

Reading the code it looks like this change actually addresses a 
regression introduced by the blamed commit, is that correct? If so 
please re-phrase the commit message accordingly.

Thanks,

Paolo