Re: [PATCH bpf-next v4 4/5] selftests/bpf: Add test for dmabuf_iter

On Thu, May 8, 2025 at 11:20 AM T.J. Mercier tjmercier@google.com wrote: [...]

+void test_dmabuf_iter(void) +{

•   struct dmabuf_iter *skel = NULL;
  

•   char buf[256];
  

•   int iter_fd;
  

•   skel = dmabuf_iter__open_and_load();
  

•   if (!ASSERT_OK_PTR(skel, "dmabuf_iter__open_and_load"))
  

•           return;
  

•   if (!ASSERT_OK(create_test_buffers(), "create_buffers"))
  

•           goto destroy;
  

•   if (!ASSERT_OK(dmabuf_iter__attach(skel), "skel_attach"))
  

•           goto destroy;
  

From here...

•   iter_fd = bpf_iter_create(bpf_link__fd(skel->links.dmabuf_collector));
  

•   if (!ASSERT_OK_FD(iter_fd, "iter_create"))
  

•           goto destroy;
  

•   while (read(iter_fd, buf, sizeof(buf)) > 0)
  

•           ; /* Read out all contents */
  

•   /* Next reads should return 0 */
  

•   ASSERT_EQ(read(iter_fd, buf, sizeof(buf)), 0, "read");
  

to here, can be a separate subtest. Then iter_fd can be moved to that subtest.

•   if (test__start_subtest("default_iter"))
  

•           subtest_dmabuf_iter_check_default_iter(skel);
  

•   close(iter_fd);
  

+destroy:

•   destroy_test_buffers();
  

•   dmabuf_iter__destroy(skel);
  

[...]