selftests: net: increase the delay for relative cmsg_time.sh test

Slow machines can delay scheduling of the packets for milliseconds.
Increase the delay to 8ms if KSFT_MACHINE_SLOW. Try to limit the
variability by moving setsockopts earlier (before we read time).

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

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

Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240510005705.43069-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/selftests/net/cmsg_sender.c b/tools/testing/selftests/net/cmsg_sender.c
index 161db24..876c2db 100644 (file)
--- a/tools/testing/selftests/net/cmsg_sender.c
+++ b/tools/testing/selftests/net/cmsg_sender.c
@@ -260,15 +260,8 @@ cs_write_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
                          SOL_IPV6, IPV6_HOPLIMIT, &opt.v6.hlimit);
 
        if (opt.txtime.ena) {
-               struct sock_txtime so_txtime = {
-                       .clockid = CLOCK_MONOTONIC,
-               };
                __u64 txtime;
 
-               if (setsockopt(fd, SOL_SOCKET, SO_TXTIME,
-                              &so_txtime, sizeof(so_txtime)))
-                       error(ERN_SOCKOPT, errno, "setsockopt TXTIME");
-
                txtime = time_start_mono.tv_sec * (1000ULL * 1000 * 1000) +
                         time_start_mono.tv_nsec +
                         opt.txtime.delay * 1000;
@@ -284,13 +277,6 @@ cs_write_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
                memcpy(CMSG_DATA(cmsg), &txtime, sizeof(txtime));
        }
        if (opt.ts.ena) {
-               __u32 val = SOF_TIMESTAMPING_SOFTWARE |
-                           SOF_TIMESTAMPING_OPT_TSONLY;
-
-               if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING,
-                              &val, sizeof(val)))
-                       error(ERN_SOCKOPT, errno, "setsockopt TIMESTAMPING");
-
                cmsg = (struct cmsghdr *)(cbuf + cmsg_len);
                cmsg_len += CMSG_SPACE(sizeof(__u32));
                if (cbuf_sz < cmsg_len)
@@ -426,6 +412,24 @@ static void ca_set_sockopts(int fd)
            setsockopt(fd, SOL_SOCKET, SO_PRIORITY,
                       &opt.sockopt.priority, sizeof(opt.sockopt.priority)))
                error(ERN_SOCKOPT, errno, "setsockopt SO_PRIORITY");
+
+       if (opt.txtime.ena) {
+               struct sock_txtime so_txtime = {
+                       .clockid = CLOCK_MONOTONIC,
+               };
+
+               if (setsockopt(fd, SOL_SOCKET, SO_TXTIME,
+                              &so_txtime, sizeof(so_txtime)))
+                       error(ERN_SOCKOPT, errno, "setsockopt TXTIME");
+       }
+       if (opt.ts.ena) {
+               __u32 val = SOF_TIMESTAMPING_SOFTWARE |
+                       SOF_TIMESTAMPING_OPT_TSONLY;
+
+               if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING,
+                              &val, sizeof(val)))
+                       error(ERN_SOCKOPT, errno, "setsockopt TIMESTAMPING");
+       }
 }
 
 int main(int argc, char *argv[])

diff --git a/tools/testing/selftests/net/cmsg_time.sh b/tools/testing/selftests/net/cmsg_time.sh
index af85267..1d7e756 100755 (executable)
--- a/tools/testing/selftests/net/cmsg_time.sh
+++ b/tools/testing/selftests/net/cmsg_time.sh
@@ -66,10 +66,13 @@ for i in "-4 $TGT4" "-6 $TGT6"; do
                 awk '/SND/ { if ($3 > 1000) print "OK"; }')
        check_result $? "$ts" "OK" "$prot - TXTIME abs"
 
-       ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t -d 1000 |
+       [ "$KSFT_MACHINE_SLOW" = yes ] && delay=8000 || delay=1000
+
+       ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t -d $delay |
                 awk '/SND/ {snd=$3}
                      /SCHED/ {sch=$3}
-                     END { if (snd - sch > 500) print "OK"; }')
+                     END { if (snd - sch > '$((delay/2))') print "OK";
+                           else print snd, "-", sch, "<", '$((delay/2))'; }')
        check_result $? "$ts" "OK" "$prot - TXTIME rel"
     done
 done