selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us

Because srtt and mrtt_us are added as args in bpf_sock_ops at
BPF_SOCK_OPS_RTT_CB, a simple check is added to make sure they are both
non-zero.

$ ./test_progs -t tcp_rtt
  #373     tcp_rtt:OK
  Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED

Suggested-by: Stanislav Fomichev <[email protected]>
Signed-off-by: Philo Lu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin KaFai Lau <[email protected]>

1 files changed, 6 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/tcp_rtt.c b/tools/testing/selftests/bpf/progs/tcp_rtt.c
index 0988d79f1587..42c729f85524 100644
--- a/tools/testing/selftests/bpf/progs/tcp_rtt.c
+++ b/tools/testing/selftests/bpf/progs/tcp_rtt.c
@@ -10,6 +10,9 @@ struct tcp_rtt_storage {
 	__u32 delivered;
 	__u32 delivered_ce;
 	__u32 icsk_retransmits;
+
+	__u32 mrtt_us;	/* args[0] */
+	__u32 srtt;	/* args[1] */
 };
 
 struct {
@@ -55,5 +58,8 @@ int _sockops(struct bpf_sock_ops *ctx)
 	storage->delivered_ce = tcp_sk->delivered_ce;
 	storage->icsk_retransmits = tcp_sk->icsk_retransmits;
 
+	storage->mrtt_us = ctx->args[0];
+	storage->srtt = ctx->args[1];
+
 	return 1;
 }