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 <sdf@google.com>
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240425161724.73707-3-lulie@linux.alibaba.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
index 8fe84da1b9b49bb6d33ca014a809f00b6eb2ab64..f2b99d95d91607044ac10077cd16f760d584565e 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
+++ b/tools/testing/selftests/bpf/prog_tests/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] */
 };
 
 static void send_byte(int fd)
@@ -83,6 +86,17 @@ static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked,
                err++;
        }
 
+       /* Precise values of mrtt and srtt are unavailable, just make sure they are nonzero */
+       if (val.mrtt_us == 0) {
+               log_err("%s: unexpected bpf_tcp_sock.args[0] (mrtt_us) %u == 0", msg, val.mrtt_us);
+               err++;
+       }
+
+       if (val.srtt == 0) {
+               log_err("%s: unexpected bpf_tcp_sock.args[1] (srtt) %u == 0", msg, val.srtt);
+               err++;
+       }
+
        return err;
 }
 

diff --git a/tools/testing/selftests/bpf/progs/tcp_rtt.c b/tools/testing/selftests/bpf/progs/tcp_rtt.c
index 0988d79f15877fe39c1a7f97266012f5acf7798c..42c729f855246d7df186648a93a2fe289934f92d 100644 (file)
--- 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;
 }