libbpf: remove likely/unlikely in xsk.h

This patch removes the use of likely and unlikely in xsk.h since they
create a dependency on Linux headers as reported by several
users. There have also been reports that the use of these decreases
performance as the compiler puts the code on two different cache lines
instead of on a single one. All in all, I think we are better off
without them.

Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h
index 1b35c40dff731ddf6fcbc917eee967e2f1d7dc9f..f264f24f06ac41ee13684260d3c5878a98c29f6f 100644 (file)
--- a/tools/lib/bpf/xsk.h
+++ b/tools/lib/bpf/xsk.h
@@ -109,7 +109,7 @@ 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 (unlikely(xsk_prod_nb_free(prod, nb) < nb))
+       if (xsk_prod_nb_free(prod, nb) < nb)
                return 0;
 
        *idx = prod->cached_prod;
@@ -133,7 +133,7 @@ static inline size_t xsk_ring_cons__peek(struct xsk_ring_cons *cons,
 {
        size_t entries = xsk_cons_nb_avail(cons, nb);
 
-       if (likely(entries > 0)) {
+       if (entries > 0) {
                /* Make sure we do not speculatively read the data before
                 * we have received the packet buffers from the ring.
                 */