[PATCH AUTOSEL 4.20 172/304] selftests/bpf: use __bpf_constant_htons in test_prog.c

[Sasha Levin <sashal@xxxxxxxxxx>]

From: Stanislav Fomichev <sdf@xxxxxxxxxx>

[ Upstream commit a0517a0f7ef23550b4484c37e2b9c2d32abebf64 ]

For some reason, my older GCC (< 4.8) isn't smart enough to optimize the
!__builtin_constant_p() branch in bpf_htons, I see:
  error: implicit declaration of function '__builtin_bswap16'

Let's use __bpf_constant_htons as suggested by Daniel Borkmann.

I tried to use simple htons, but it produces the following:
  test_progs.c:54:17: error: braced-group within expression allowed only
  inside a function
    .eth.h_proto = htons(ETH_P_IP),

Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 tools/testing/selftests/bpf/test_progs.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index 2d3c04f45530..6ac7232b0fde 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -51,10 +51,10 @@ static struct {
 	struct iphdr iph;
 	struct tcphdr tcp;
 } __packed pkt_v4 = {
-	.eth.h_proto = bpf_htons(ETH_P_IP),
+	.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
 	.iph.ihl = 5,
 	.iph.protocol = 6,
-	.iph.tot_len = bpf_htons(MAGIC_BYTES),
+	.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
 	.tcp.urg_ptr = 123,
 };
 
@@ -64,9 +64,9 @@ static struct {
 	struct ipv6hdr iph;
 	struct tcphdr tcp;
 } __packed pkt_v6 = {
-	.eth.h_proto = bpf_htons(ETH_P_IPV6),
+	.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
 	.iph.nexthdr = 6,
-	.iph.payload_len = bpf_htons(MAGIC_BYTES),
+	.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
 	.tcp.urg_ptr = 123,
 };
 
-- 
2.19.1