Re: [PATCH net-next v3] page_pool: check for dma_sync_size earlier

[Jason Xing]

On Mon, Jan 6, 2025 at 11:02 AM Furong Xu <0x1207@xxxxxxxxx> wrote:
>
> Setting dma_sync_size to 0 is not illegal, fec_main.c and ravb_main.c
> already did.
> We can save a couple of function calls if check for dma_sync_size earlier.
>
> This is a micro optimization, about 0.6% PPS performance improvement
> has been observed on a single Cortex-A53 CPU core with 64 bytes UDP RX
> traffic test.
>
> Before this patch:
> The average of packets per second is 234026 in one minute.
>
> After this patch:
> The average of packets per second is 235537 in one minute.

Sorry, I keep skeptical that this small improvement can be statically
observed? What exact tool or benchmark are you using, I wonder?

Thanks,
Jason