selftests/xsk: add timeout for Tx thread

Add a timeout for the transmission thread. If packets are not
completed properly, for some reason, the test harness would previously
get stuck forever in a while loop. But with this patch, this timeout
will trigger, flag the test as a failure, and continue with the next
test.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-3-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index c595c0b6541773f807dc7ec45c039c1e0d729ec7..514fe994e02be7befbfc36ee7614f1ef76e1ba16 100644 (file)
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -1216,10 +1216,29 @@ static int __send_pkts(struct ifobject *ifobject, struct pollfd *fds, bool timeo
        return TEST_CONTINUE;
 }
 
-static void wait_for_tx_completion(struct xsk_socket_info *xsk)
+static int wait_for_tx_completion(struct xsk_socket_info *xsk)
 {
-       while (xsk->outstanding_tx)
+       struct timeval tv_end, tv_now, tv_timeout = {THREAD_TMOUT, 0};
+       int ret;
+
+       ret = gettimeofday(&tv_now, NULL);
+       if (ret)
+               exit_with_error(errno);
+       timeradd(&tv_now, &tv_timeout, &tv_end);
+
+       while (xsk->outstanding_tx) {
+               ret = gettimeofday(&tv_now, NULL);
+               if (ret)
+                       exit_with_error(errno);
+               if (timercmp(&tv_now, &tv_end, >)) {
+                       ksft_print_msg("ERROR: [%s] Transmission loop timed out\n", __func__);
+                       return TEST_FAILURE;
+               }
+
                complete_pkts(xsk, BATCH_SIZE);
+       }
+
+       return TEST_PASS;
 }
 
 static int send_pkts(struct test_spec *test, struct ifobject *ifobject)
@@ -1242,8 +1261,7 @@ static int send_pkts(struct test_spec *test, struct ifobject *ifobject)
                        return ret;
        }
 
-       wait_for_tx_completion(ifobject->xsk);
-       return TEST_PASS;
+       return wait_for_tx_completion(ifobject->xsk);
 }
 
 static int get_xsk_stats(struct xsk_socket *xsk, struct xdp_statistics *stats)