Re: [PATCH net-next v16 05/13] page_pool: devmem support
From: Jakub Kicinski <kuba@kernel.org>
Date: 2024-07-11 01:22:05
Also in:
bpf, dri-devel, linux-alpha, linux-arch, linux-doc, linux-kselftest, linux-media, linux-mips, linux-mm, lkml, netdev, sparclinux
On Wed, 10 Jul 2024 13:29:03 -0700 Mina Almasry wrote:
quoted hunk ↗ jump to hunk
If we want to add __skb_frag_ref() support for net_iov I suggest something like:diff --git a/include/linux/skbuff_ref.h b/include/linux/skbuff_ref.h index 0f3c58007488a..02f7f4c7d4821 100644 --- a/include/linux/skbuff_ref.h +++ b/include/linux/skbuff_ref.h@@ -17,7 +17,13 @@ */ static inline void __skb_frag_ref(skb_frag_t *frag) { - get_page(skb_frag_page(frag)); + netmem_ref netmem = skb_frag_netmem(frag); + + /* netmem always uses pp-refs for refcounting. Never non-pp refs. */ + if (!netmem_is_net_iov(netmem)) + get_page(netmem_to_page(netmem)); + else + page_pool_ref_netmem(netmem); }
Probably not much better since freeing still looks at the recycle bit. Eric and Willem acked patch 8, maybe it works, and if it doesn't we know who to call :) I can't point out any case that won't work so if y'all think this is fine, let's leave it.