Re: [PATCH bpf-next v3 4/6] selftests/bpf: Monitor traffic for tc_redirect.

[Geliang Tang <geliang@xxxxxxxxxx>]

On Mon, 2024-07-29 at 17:27 -0700, Kui-Feng Lee wrote:
> Enable traffic monitoring for the test case tc_redirect.
> 
> Signed-off-by: Kui-Feng Lee <thinker.li@xxxxxxxxx>
> ---
>  .../selftests/bpf/prog_tests/tc_redirect.c    | 48 ++++++++++++++---
> --
>  1 file changed, 36 insertions(+), 12 deletions(-)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c
> b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c
> index 327d51f59142..46d397c5c79a 100644
> --- a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c
> +++ b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c
> @@ -68,6 +68,7 @@
>  		__FILE__, __LINE__, strerror(errno), ##__VA_ARGS__)
>  
>  static const char * const namespaces[] = {NS_SRC, NS_FWD, NS_DST,
> NULL};
> +static struct netns_obj *netns_objs[3];
>  
>  static int write_file(const char *path, const char *newval)
>  {
> @@ -85,29 +86,52 @@ static int write_file(const char *path, const
> char *newval)
>  	return 0;
>  }
>  
> -static int netns_setup_namespaces(const char *verb)
> +enum NETNS_VERB {
> +	NETNS_ADD,
> +	NETNS_DEL,
> +};
> +
> +static int netns_setup_namespaces(enum NETNS_VERB verb)
>  {
>  	const char * const *ns = namespaces;
> -	char cmd[128];
> +	struct netns_obj **ns_obj = netns_objs;
>  
>  	while (*ns) {
> -		snprintf(cmd, sizeof(cmd), "ip netns %s %s", verb,
> *ns);
> -		if (!ASSERT_OK(system(cmd), cmd))
> -			return -1;
> +		if (verb == NETNS_ADD) {

Maybe better to keep "verb" parameter as "char *", and use

		if (!strcmp(verb, "add"))

here instead?

> +			*ns_obj = netns_new(*ns, false);
> +			if (!*ns_obj) {
> +				log_err("netns_new failed");
> +				return -1;
> +			}
> +		} else {
> +			if (!*ns_obj) {
> +				log_err("netns_obj is NULL");
> +				return -1;
> +			}
> +			netns_free(*ns_obj);
> +			*ns_obj = NULL;
> +		}
>  		ns++;
> +		ns_obj++;
>  	}
>  	return 0;
>  }
>  
> -static void netns_setup_namespaces_nofail(const char *verb)
> +static void netns_setup_namespaces_nofail(enum NETNS_VERB verb)
>  {
>  	const char * const *ns = namespaces;
> -	char cmd[128];
> +	struct netns_obj **ns_obj = netns_objs;
>  
>  	while (*ns) {
> -		snprintf(cmd, sizeof(cmd), "ip netns %s %s >
> /dev/null 2>&1", verb, *ns);
> -		system(cmd);
> +		if (verb == NETNS_ADD) {
> +			*ns_obj = netns_new(*ns, false);
> +		} else {
> +			if (*ns_obj)
> +				netns_free(*ns_obj);
> +			*ns_obj = NULL;
> +		}
>  		ns++;
> +		ns_obj++;
>  	}
>  }
>  
> @@ -1250,17 +1274,17 @@ static void test_tc_redirect_peer_l3(struct
> netns_setup_result *setup_result)
>  	({                                                          
>                         \
>  		struct netns_setup_result setup_result = { .dev_mode
> = mode, };             \
>  		if
> (test__start_subtest(#name))                                         
>     \
> -			if (ASSERT_OK(netns_setup_namespaces("add"),
> "setup namespaces")) { \
> +			if
> (ASSERT_OK(netns_setup_namespaces(NETNS_ADD), "setup namespaces")) {
> \
>  				if
> (ASSERT_OK(netns_setup_links_and_routes(&setup_result),  \
>  					      "setup links and
> routes"))                    \
>  					test_ ##
> name(&setup_result);                       \
> -
> 				netns_setup_namespaces("delete");                           \
> +				netns_setup_namespaces(NETNS_DEL);  
>                         \
>  			}                                           
>                         \
>  	})
>  
>  static void *test_tc_redirect_run_tests(void *arg)
>  {
> -	netns_setup_namespaces_nofail("delete");
> +	netns_setup_namespaces_nofail(NETNS_DEL);
>  
>  	RUN_TEST(tc_redirect_peer, MODE_VETH);
>  	RUN_TEST(tc_redirect_peer, MODE_NETKIT);