Re: [PATCH net-next V2 06/11] net/mlx5e: SHAMPO: Separate pool for headers

Mina Almasry
2025-05-22T23:24:49Z

On Thu, May 22, 2025 at 4:09 PM Saeed Mahameed <saeed@kernel.org> wrote:
>
> On 22 May 15:30, Jakub Kicinski wrote:
> >On Fri, 23 May 2025 00:41:21 +0300 Tariq Toukan wrote:
> >> Allocate a separate page pool for headers when SHAMPO is enabled.
> >> This will be useful for adding support to zc page pool, which has to be
> >> different from the headers page pool.
> >
> >Could you explain why always allocate a separate pool?
>
> Better flow management, 0 conditional code on data path to alloc/return
> header buffers, since in mlx5 we already have separate paths to handle
> header, we don't have/need bnxt_separate_head_pool() and
> rxr->need_head_pool spread across the code..
>
> Since we alloc and return pages in bulks, it makes more sense to manage
> headers and data in separate pools if we are going to do it anyway for
> "undreadable_pools", and when there's no performance impact.
>

Are you allocating full pages for each incoming header (which is much
smaller than a page)? Or are you reusing the same PAGE_SIZE from the
page_pool to store multiple headers?

--
Thanks,
Mina