Re: [PATCH net-next 2/9] net: skbuff: don't include <net/page_pool/types.h> to <linux/skbuff.h>

From: Yunsheng Lin
Date: Fri Jul 28 2023 - 08:04:16 EST


On 2023/7/27 22:43, Alexander Lobakin wrote:
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c

...

> +bool page_pool_return_skb_page(struct page *page, bool napi_safe)

Still having the 'page_pool_' prefix seems odd here when it is in the
skbuff.c where most have skb_ or napi_ prefix, is it better to rename
it to something like napi_return_page_pool_page()?

> +{
> + struct napi_struct *napi;
> + struct page_pool *pp;
> + bool allow_direct;
> +
> + page = compound_head(page);
> +
> + /* page->pp_magic is OR'ed with PP_SIGNATURE after the allocation
> + * in order to preserve any existing bits, such as bit 0 for the
> + * head page of compound page and bit 1 for pfmemalloc page, so
> + * mask those bits for freeing side when doing below checking,
> + * and page_is_pfmemalloc() is checked in __page_pool_put_page()
> + * to avoid recycling the pfmemalloc page.
> + */
> + if (unlikely((page->pp_magic & ~0x3UL) != PP_SIGNATURE))
> + return false;
> +
> + pp = page->pp;
> +
> + /* Allow direct recycle if we have reasons to believe that we are
> + * in the same context as the consumer would run, so there's
> + * no possible race.
> + */
> + napi = READ_ONCE(pp->p.napi);
> + allow_direct = napi_safe && napi &&
> + READ_ONCE(napi->list_owner) == smp_processor_id();
> +
> + /* Driver set this to memory recycling info. Reset it on recycle.
> + * This will *not* work for NIC using a split-page memory model.
> + * The page will be returned to the pool here regardless of the
> + * 'flipped' fragment being in use or not.
> + */
> + page_pool_put_full_page(pp, page, allow_direct);
> +
> + return true;
> +}
> +EXPORT_SYMBOL(page_pool_return_skb_page);
> +
> static bool skb_pp_recycle(struct sk_buff *skb, void *data, bool napi_safe)
> {
> if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
>