From: Jason Xing kernelxing@tencent.com
When I was trying to modify the tx timestamping feature, I found that running "./txtimestamp -4 -C -L 127.0.0.1" didn't reflect the fact properly.
In this selftest file, we respectively test three tx generation flags. With the generation and report flag enabled, we expect that the timestamp must be returned to the userspace unless 1) generating the timestamp fails, 2) reporting the timestamp fails. So we should test if the timestamps can be read and parsed succuessfuly in txtimestamp.c, or else there is a bug in the kernel.
After adding the check so that running ./txtimestamp will reflect the result correctly like this if there is an error in kernel: protocol: TCP payload: 10 server port: 9000
family: INET test SND USR: 1725458477 s 667997 us (seq=0, len=0) Failed to parse timestamps USR: 1725458477 s 718128 us (seq=0, len=0) Failed to parse timestamps USR: 1725458477 s 768273 us (seq=0, len=0) Failed to parse timestamps USR: 1725458477 s 818416 us (seq=0, len=0) Failed to parse timestamps ...
Signed-off-by: Jason Xing kernelxing@tencent.com --- I'm not sure if I should also check if the cur->tv_sec or cur->tv_nsec is zero in __print_timestamp(). Could it be valid when either of them is zero? --- tools/testing/selftests/net/txtimestamp.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/tools/testing/selftests/net/txtimestamp.c b/tools/testing/selftests/net/txtimestamp.c index ec60a16c9307..b69aae840a67 100644 --- a/tools/testing/selftests/net/txtimestamp.c +++ b/tools/testing/selftests/net/txtimestamp.c @@ -358,6 +358,10 @@ static void __recv_errmsg_cmsg(struct msghdr *msg, int payload_len)
if (batch > 1) fprintf(stderr, "batched %d timestamps\n", batch); + else if (!batch) { + fprintf(stderr, "Failed to parse timestamps\n"); + test_failed = true; + } }
static int recv_errmsg(int fd)