When an AF_XDP application received X packets, it does not mean X
frames can be stuffed into the producer ring. To make it easier for
AF_XDP applications this API allows them to check how many frames can
be added into the ring.
Signed-off-by: Eelco Chaudron <echau...@redhat.com>
---
v1 -> v2
- Renamed xsk_ring_prod__free() to xsk_ring_prod__nb_free()
- Add caching so it will only touch global state when needed
tools/lib/bpf/xsk.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h
index 82ea71a0f3ec..6acb81102346 100644
--- a/tools/lib/bpf/xsk.h
+++ b/tools/lib/bpf/xsk.h
@@ -76,11 +76,11 @@ xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx,
__u32 idx)
return &descs[idx & rx->mask];
}
-static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
+static inline __u32 xsk_prod__nb_free(struct xsk_ring_prod *r, __u32 nb)
{
__u32 free_entries = r->cached_cons - r->cached_prod;
- if (free_entries >= nb)
+ if (free_entries >= nb && nb != 0)
return free_entries;
/* Refresh the local tail pointer.
@@ -110,7 +110,7 @@ static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons
*r, __u32 nb)
static inline size_t xsk_ring_prod__reserve(struct xsk_ring_prod *prod,
size_t nb, __u32 *idx)
{
- if (xsk_prod_nb_free(prod, nb) < nb)
+ if (xsk_prod__nb_free(prod, nb) < nb)
return 0;
*idx = prod->cached_prod;
--
2.20.1
