xsk: Get rid of xdp_buff_xsk::xskb_list_node

Let's bring xdp_buff_xsk back to occupying 2 cachelines by removing
xskb_list_node - for the purpose of gathering the xskb frags
free_list_node can be used, head of the list (xsk_buff_pool::xskb_list)
stays as-is, just reuse the node ptr.

It is safe to do as a single xdp_buff_xsk can never reside in two
pool's lists simultaneously.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20241007122458.282590-2-maciej.fijalkowski@intel.com
This commit is contained in:
Maciej Fijalkowski 2024-10-07 14:24:53 +02:00 committed by Daniel Borkmann
parent a8057ed23a
commit b692bf9a75
4 changed files with 9 additions and 11 deletions

View File

@ -126,8 +126,8 @@ static inline void xsk_buff_free(struct xdp_buff *xdp)
if (likely(!xdp_buff_has_frags(xdp)))
goto out;
list_for_each_entry_safe(pos, tmp, xskb_list, xskb_list_node) {
list_del(&pos->xskb_list_node);
list_for_each_entry_safe(pos, tmp, xskb_list, free_list_node) {
list_del(&pos->free_list_node);
xp_free(pos);
}
@ -140,7 +140,7 @@ static inline void xsk_buff_add_frag(struct xdp_buff *xdp)
{
struct xdp_buff_xsk *frag = container_of(xdp, struct xdp_buff_xsk, xdp);
list_add_tail(&frag->xskb_list_node, &frag->pool->xskb_list);
list_add_tail(&frag->free_list_node, &frag->pool->xskb_list);
}
static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
@ -150,9 +150,9 @@ static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
struct xdp_buff_xsk *frag;
frag = list_first_entry_or_null(&xskb->pool->xskb_list,
struct xdp_buff_xsk, xskb_list_node);
struct xdp_buff_xsk, free_list_node);
if (frag) {
list_del(&frag->xskb_list_node);
list_del(&frag->free_list_node);
ret = &frag->xdp;
}
@ -163,7 +163,7 @@ static inline void xsk_buff_del_tail(struct xdp_buff *tail)
{
struct xdp_buff_xsk *xskb = container_of(tail, struct xdp_buff_xsk, xdp);
list_del(&xskb->xskb_list_node);
list_del(&xskb->free_list_node);
}
static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
@ -172,7 +172,7 @@ static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
struct xdp_buff_xsk *frag;
frag = list_last_entry(&xskb->pool->xskb_list, struct xdp_buff_xsk,
xskb_list_node);
free_list_node);
return &frag->xdp;
}

View File

@ -30,7 +30,6 @@ struct xdp_buff_xsk {
struct xsk_buff_pool *pool;
u64 orig_addr;
struct list_head free_list_node;
struct list_head xskb_list_node;
};
#define XSK_CHECK_PRIV_TYPE(t) BUILD_BUG_ON(sizeof(t) > offsetofend(struct xdp_buff_xsk, cb))

View File

@ -171,14 +171,14 @@ static int xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len)
return 0;
xskb_list = &xskb->pool->xskb_list;
list_for_each_entry_safe(pos, tmp, xskb_list, xskb_list_node) {
list_for_each_entry_safe(pos, tmp, xskb_list, free_list_node) {
if (list_is_singular(xskb_list))
contd = 0;
len = pos->xdp.data_end - pos->xdp.data;
err = __xsk_rcv_zc(xs, pos, len, contd);
if (err)
goto err;
list_del(&pos->xskb_list_node);
list_del(&pos->free_list_node);
}
return 0;

View File

@ -102,7 +102,6 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
xskb->pool = pool;
xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
INIT_LIST_HEAD(&xskb->free_list_node);
INIT_LIST_HEAD(&xskb->xskb_list_node);
if (pool->unaligned)
pool->free_heads[i] = xskb;
else