On Sun, 2024-02-04 at 21:29 -0800, Yonghong Song wrote:
> Recently, when running './test_progs -j', I occasionally hit the
> following errors:
>
> test_lwt_redirect:PASS:pthread_create 0 nsec
> test_lwt_redirect_run:FAIL:netns_create unexpected error: 256 (errno 0)
> #142/2 lwt_redirect/lwt_redirect_normal_nomac:FAIL
> #142 lwt_redirect:FAIL
> test_lwt_reroute:PASS:pthread_create 0 nsec
> test_lwt_reroute_run:FAIL:netns_create unexpected error: 256 (errno 0)
> test_lwt_reroute:PASS:pthread_join 0 nsec
> #143/2 lwt_reroute/lwt_reroute_qdisc_dropped:FAIL
> #143 lwt_reroute:FAIL
>
> The netns_create() definition looks like below:
>
> #define NETNS "ns_lwt"
> static inline int netns_create(void)
> {
> return system("ip netns add " NETNS);
> }
>
> One possibility is that both lwt_redirect and lwt_reroute create
> netns with the same name "ns_lwt" which may cause conflict. I tried
> the following example:
> $ sudo ip netns add abc
> $ echo $?
> 0
> $ sudo ip netns add abc
> Cannot create namespace file "/var/run/netns/abc": File exists
> $ echo $?
> 1
> $
>
> The return code for above netns_create() is 256. The internet search
> suggests that the return value for 'ip netns add ns_lwt' is 1, which
> matches the above 'sudo ip netns add abc' example.
>
> This patch tried to use different netns names for two tests to avoid
> 'ip netns add <name>' failure.
>
> I ran './test_progs -j' 10 times and all succeeded with
> lwt_redirect/lwt_reroute tests.
>
> Signed-off-by: Yonghong Song <yonghong.song@xxxxxxxxx>
> ---
Tested-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
Can confirm, w/o this patch tests reliably step on each others toes
when using command:
./test_progs -j -a "lwt_*"
This patch resolves the issue.
