diff mbox series

[net-next,1/2] selftests: net: fix timestamp not arriving in cmsg_time.sh

Message ID 20240510005705.43069-1-kuba@kernel.org (mailing list archive)
State Accepted
Commit 2d3b8dfd82d76b1295167c6453d683ab99e50794
Headers show
Series [net-next,1/2] selftests: net: fix timestamp not arriving in cmsg_time.sh | expand

Commit Message

Jakub Kicinski May 10, 2024, 12:57 a.m. UTC
On slow machines the SND timestamp sometimes doesn't arrive before
we quit. The test only waits as long as the packet delay, so it's
easy for a race condition to happen.

Double the wait but do a bit of polling, once the SND timestamp
arrives there's no point to wait any longer.

This fixes the "TXTIME abs" failures on debug kernels, like:

   Case ICMPv4  - TXTIME abs returned '', expected 'OK'

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
CC: shuah@kernel.org
CC: linux-kselftest@vger.kernel.org
---
 tools/testing/selftests/net/cmsg_sender.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

Comments

Willem de Bruijn May 10, 2024, 2:49 a.m. UTC | #1
Jakub Kicinski wrote:
> On slow machines the SND timestamp sometimes doesn't arrive before
> we quit. The test only waits as long as the packet delay, so it's
> easy for a race condition to happen.
> 
> Double the wait but do a bit of polling, once the SND timestamp
> arrives there's no point to wait any longer.
> 
> This fixes the "TXTIME abs" failures on debug kernels, like:
> 
>    Case ICMPv4  - TXTIME abs returned '', expected 'OK'
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Reviewed-by: Willem de Bruijn <willemb@google.com>

> diff --git a/tools/testing/selftests/net/cmsg_sender.c b/tools/testing/selftests/net/cmsg_sender.c
> index c79e65581dc3..f25268504937 100644
> --- a/tools/testing/selftests/net/cmsg_sender.c
> +++ b/tools/testing/selftests/net/cmsg_sender.c
> @@ -333,16 +333,17 @@ static const char *cs_ts_info2str(unsigned int info)
>  	return "unknown";
>  }
>  
> -static void
> +static unsigned long
>  cs_read_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
>  {
>  	struct sock_extended_err *see;
>  	struct scm_timestamping *ts;
> +	unsigned int ts_seen = 0;

nit: mixing unsigned long and unsigned int
Jakub Kicinski May 11, 2024, 1:23 a.m. UTC | #2
On Thu, 09 May 2024 22:49:50 -0400 Willem de Bruijn wrote:
> >  	struct sock_extended_err *see;
> >  	struct scm_timestamping *ts;
> > +	unsigned int ts_seen = 0;  
> 
> nit: mixing unsigned long and unsigned int

Fixed when applying, thanks!
patchwork-bot+netdevbpf@kernel.org May 11, 2024, 1:30 a.m. UTC | #3
Hello:

This series was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu,  9 May 2024 17:57:04 -0700 you wrote:
> On slow machines the SND timestamp sometimes doesn't arrive before
> we quit. The test only waits as long as the packet delay, so it's
> easy for a race condition to happen.
> 
> Double the wait but do a bit of polling, once the SND timestamp
> arrives there's no point to wait any longer.
> 
> [...]

Here is the summary with links:
  - [net-next,1/2] selftests: net: fix timestamp not arriving in cmsg_time.sh
    https://git.kernel.org/netdev/net-next/c/2d3b8dfd82d7
  - [net-next,2/2] selftests: net: increase the delay for relative cmsg_time.sh test
    https://git.kernel.org/netdev/net-next/c/b9d5f5711dd8

You are awesome, thank you!
diff mbox series

Patch

diff --git a/tools/testing/selftests/net/cmsg_sender.c b/tools/testing/selftests/net/cmsg_sender.c
index c79e65581dc3..f25268504937 100644
--- a/tools/testing/selftests/net/cmsg_sender.c
+++ b/tools/testing/selftests/net/cmsg_sender.c
@@ -333,16 +333,17 @@  static const char *cs_ts_info2str(unsigned int info)
 	return "unknown";
 }
 
-static void
+static unsigned long
 cs_read_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
 {
 	struct sock_extended_err *see;
 	struct scm_timestamping *ts;
+	unsigned int ts_seen = 0;
 	struct cmsghdr *cmsg;
 	int i, err;
 
 	if (!opt.ts.ena)
-		return;
+		return 0;
 	msg->msg_control = cbuf;
 	msg->msg_controllen = cbuf_sz;
 
@@ -396,8 +397,11 @@  cs_read_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
 			printf(" %5s ts%d %lluus\n",
 			       cs_ts_info2str(see->ee_info),
 			       i, rel_time);
+			ts_seen |= 1 << see->ee_info;
 		}
 	}
+
+	return ts_seen;
 }
 
 static void ca_set_sockopts(int fd)
@@ -509,10 +513,16 @@  int main(int argc, char *argv[])
 	err = ERN_SUCCESS;
 
 	if (opt.ts.ena) {
-		/* Make sure all timestamps have time to loop back */
-		usleep(opt.txtime.delay);
+		unsigned long seen;
+		int i;
 
-		cs_read_cmsg(fd, &msg, cbuf, sizeof(cbuf));
+		/* Make sure all timestamps have time to loop back */
+		for (i = 0; i < 40; i++) {
+			seen = cs_read_cmsg(fd, &msg, cbuf, sizeof(cbuf));
+			if (seen & (1 << SCM_TSTAMP_SND))
+				break;
+			usleep(opt.txtime.delay / 20);
+		}
 	}
 
 err_out: