Re: [PATCH bpf-next 2/5] selftests/bpf: add tc helpers

On 10/17/25 7:29 AM, Alexis Lothoré (eBPF Foundation) wrote:

diff --git a/tools/testing/selftests/bpf/tc_helpers.c b/tools/testing/selftests/bpf/tc_helpers.c new file mode 100644 index 0000000000000000000000000000000000000000..d668e10e3ebad8f8e04862f5c2b3ccd487fe8fa6 --- /dev/null +++ b/tools/testing/selftests/bpf/tc_helpers.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0-only +#define _GNU_SOURCE

+#include <net/if.h> +#include "tc_helpers.h" +#include "test_progs.h"

+static int attach_tc_prog(int ifindex, int igr_fd, int egr_fd)

This one looks good but change it to "int tc_prog_attach(const char *dev, int ingress_fd, int egress_fd)". Remove static. Take "const char *dev" as the arg. Add it to network_helpers.[ch] instead of creating a new source file.

+{

• DECLARE_LIBBPF_OPTS(bpf_tc_hook, hook, .ifindex = ifindex,

• 	    .attach_point = BPF_TC_INGRESS | BPF_TC_EGRESS);
  

• DECLARE_LIBBPF_OPTS(bpf_tc_opts, opts1, .handle = 1,

• 	    .priority = 1, .prog_fd = igr_fd);
  

• DECLARE_LIBBPF_OPTS(bpf_tc_opts, opts2, .handle = 1,

• 	    .priority = 1, .prog_fd = egr_fd);
  

• int ret;
• ret = bpf_tc_hook_create(&hook);
• if (!ASSERT_OK(ret, "create tc hook"))

• return ret;
  

• if (igr_fd >= 0) {

• hook.attach_point = BPF_TC_INGRESS;
  

• ret = bpf_tc_attach(&hook, &opts1);
  

• if (!ASSERT_OK(ret, "bpf_tc_attach")) {
  

• 	bpf_tc_hook_destroy(&hook);
  

• 	return ret;
  

• }
  

• }
• if (egr_fd >= 0) {

• hook.attach_point = BPF_TC_EGRESS;
  

• ret = bpf_tc_attach(&hook, &opts2);
  

• if (!ASSERT_OK(ret, "bpf_tc_attach")) {
  

• 	bpf_tc_hook_destroy(&hook);
  

• 	return ret;
  

• }
  

• }
• return 0;

+}

+int generic_attach(const char *dev, int igr_fd, int egr_fd) +{

• int ifindex;
• if (!ASSERT_OK_FD(igr_fd, "check ingress fd"))

• return -1;
  

• if (!ASSERT_OK_FD(egr_fd, "check egress fd"))

• return -1;
  

• ifindex = if_nametoindex(dev);
• if (!ASSERT_NEQ(ifindex, 0, "get ifindex"))

• return -1;
  

• return attach_tc_prog(ifindex, igr_fd, egr_fd);

+}

+int generic_attach_igr(const char *dev, int igr_fd) +{

• int ifindex;
• if (!ASSERT_OK_FD(igr_fd, "check ingress fd"))

• return -1;
  

• ifindex = if_nametoindex(dev);
• if (!ASSERT_NEQ(ifindex, 0, "get ifindex"))

• return -1;
  

• return attach_tc_prog(ifindex, igr_fd, -1);

+}

+int generic_attach_egr(const char *dev, int egr_fd) +{

• int ifindex;
• if (!ASSERT_OK_FD(egr_fd, "check egress fd"))

• return -1;
  

• ifindex = if_nametoindex(dev);
• if (!ASSERT_NEQ(ifindex, 0, "get ifindex"))

• return -1;
  

• return attach_tc_prog(ifindex, -1, egr_fd);

+}

These three generic_attach_* is a bit overkill for network_helpers.c.

Change test_tunnel.c to directly use tc_prog_attach().

diff --git a/tools/testing/selftests/bpf/tc_helpers.h b/tools/testing/selftests/bpf/tc_helpers.h new file mode 100644 index 0000000000000000000000000000000000000000..d31abe33f9d80dadd8f829bcf9a68cfd744c3b99 --- /dev/null +++ b/tools/testing/selftests/bpf/tc_helpers.h

This new file is not needed also. Use the network_helpers.h.