[PATCH bpf-next v1 2/2] xdp: remove unused {__,}xdp_release_frame()

Alexander Lobakin
2023-03-01T16:04:23Z

__xdp_build_skb_from_frame() was the last user of
{__,}xdp_release_frame(), which detaches pages from the Page Pool.
All the consumers now recycle Page Pool skbs and page, except mlx5,
stmmac and tsnep drivers, which use page_pool_release_page() directly
(might change one day). It's safe to assume this functionality is not
needed anymore and can be removed (in favor of recycling).

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
---
include/net/xdp.h | 29 -----------------------------
net/core/xdp.c | 15 ---------------
2 files changed, 44 deletions(-)

diff --git a/include/net/xdp.h b/include/net/xdp.h
index d517bfac937b..5393b3ebe56e 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -317,35 +317,6 @@ void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq);
void xdp_return_frame_bulk(struct xdp_frame *xdpf,
struct xdp_frame_bulk *bq);

-/* When sending xdp_frame into the network stack, then there is no
- * return point callback, which is needed to release e.g. DMA-mapping
- * resources with page_pool. Thus, have explicit function to release
- * frame resources.
- */
-void __xdp_release_frame(void *data, struct xdp_mem_info *mem);
-static inline void xdp_release_frame(struct xdp_frame *xdpf)
-{
- struct xdp_mem_info *mem = &xdpf->mem;
- struct skb_shared_info *sinfo;
- int i;
-
- /* Curr only page_pool needs this */
- if (mem->type != MEM_TYPE_PAGE_POOL)
- return;
-
- if (likely(!xdp_frame_has_frags(xdpf)))
- goto out;
-
- sinfo = xdp_get_shared_info_from_frame(xdpf);
- for (i = 0; i < sinfo->nr_frags; i++) {
- struct page *page = skb_frag_page(&sinfo->frags[i]);
-
- __xdp_release_frame(page_address(page), mem);
- }
-out:
- __xdp_release_frame(xdpf->data, mem);
-}
-
static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf)
{
struct skb_shared_info *sinfo;
diff --git a/net/core/xdp.c b/net/core/xdp.c
index a2237cfca8e9..8d3ad315f18d 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -531,21 +531,6 @@ void xdp_return_buff(struct xdp_buff *xdp)
}
EXPORT_SYMBOL_GPL(xdp_return_buff);

-/* Only called for MEM_TYPE_PAGE_POOL see xdp.h */
-void __xdp_release_frame(void *data, struct xdp_mem_info *mem)
-{
- struct xdp_mem_allocator *xa;
- struct page *page;
-
- rcu_read_lock();
- xa = rhashtable_lookup(mem_id_ht, &mem->id, mem_id_rht_params);
- page = virt_to_head_page(data);
- if (xa)
- page_pool_release_page(xa->page_pool, page);
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(__xdp_release_frame);
-
void xdp_attachment_setup(struct xdp_attachment_info *info,
struct netdev_bpf *bpf)
{
--
2.39.2