[PATCH bpf-next 2/4] selftests: bpf: Add helper to compare socket cookies

[Lorenz Bauer]

We compare socket cookies to ensure that insertion into a sockmap worked.
Pull this out into a helper function for use in other tests.

Signed-off-by: Lorenz Bauer <l...@cloudflare.com>
---
 .../selftests/bpf/prog_tests/sockmap_basic.c  | 50 +++++++++++++------
 1 file changed, 36 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c 
b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
index 4b7a527e7e82..67d3301bdf81 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
@@ -50,6 +50,37 @@ static int connected_socket_v4(void)
        return -1;
 }
 
+static void compare_cookies(struct bpf_map *src, struct bpf_map *dst)
+{
+       __u32 i, max_entries = bpf_map__max_entries(src);
+       int err, duration, src_fd, dst_fd;
+
+       src_fd = bpf_map__fd(src);
+       dst_fd = bpf_map__fd(dst);
+
+       for (i = 0; i < max_entries; i++) {
+               __u64 src_cookie, dst_cookie;
+
+               err = bpf_map_lookup_elem(src_fd, &i, &src_cookie);
+               if (err && errno == ENOENT) {
+                       err = bpf_map_lookup_elem(dst_fd, &i, &dst_cookie);
+                       CHECK(!err, "map_lookup_elem(dst)", "element %u not 
deleted\n", i);
+                       CHECK(err && errno != ENOENT, "map_lookup_elem(dst)", 
"%s\n",
+                             strerror(errno));
+                       continue;
+               }
+               if (CHECK(err, "lookup_elem(src)", "%s\n", strerror(errno)))
+                       continue;
+
+               err = bpf_map_lookup_elem(dst_fd, &i, &dst_cookie);
+               if (CHECK(err, "lookup_elem(dst)", "%s\n", strerror(errno)))
+                       continue;
+
+               CHECK(dst_cookie != src_cookie, "cookie mismatch",
+                     "%llu != %llu (pos %u)\n", dst_cookie, src_cookie, i);
+       }
+}
+
 /* Create a map, populate it with one socket, and free the map. */
 static void test_sockmap_create_update_free(enum bpf_map_type map_type)
 {
@@ -109,9 +140,9 @@ static void test_skmsg_helpers(enum bpf_map_type map_type)
 static void test_sockmap_update(enum bpf_map_type map_type)
 {
        struct bpf_prog_test_run_attr tattr;
-       int err, prog, src, dst, duration = 0;
+       int err, prog, src, duration = 0;
        struct test_sockmap_update *skel;
-       __u64 src_cookie, dst_cookie;
+       struct bpf_map *dst_map;
        const __u32 zero = 0;
        char dummy[14] = {0};
        __s64 sk;
@@ -127,18 +158,14 @@ static void test_sockmap_update(enum bpf_map_type 
map_type)
        prog = bpf_program__fd(skel->progs.copy_sock_map);
        src = bpf_map__fd(skel->maps.src);
        if (map_type == BPF_MAP_TYPE_SOCKMAP)
-               dst = bpf_map__fd(skel->maps.dst_sock_map);
+               dst_map = skel->maps.dst_sock_map;
        else
-               dst = bpf_map__fd(skel->maps.dst_sock_hash);
+               dst_map = skel->maps.dst_sock_hash;
 
        err = bpf_map_update_elem(src, &zero, &sk, BPF_NOEXIST);
        if (CHECK(err, "update_elem(src)", "errno=%u\n", errno))
                goto out;
 
-       err = bpf_map_lookup_elem(src, &zero, &src_cookie);
-       if (CHECK(err, "lookup_elem(src, cookie)", "errno=%u\n", errno))
-               goto out;
-
        tattr = (struct bpf_prog_test_run_attr){
                .prog_fd = prog,
                .repeat = 1,
@@ -151,12 +178,7 @@ static void test_sockmap_update(enum bpf_map_type map_type)
                       "errno=%u retval=%u\n", errno, tattr.retval))
                goto out;
 
-       err = bpf_map_lookup_elem(dst, &zero, &dst_cookie);
-       if (CHECK(err, "lookup_elem(dst, cookie)", "errno=%u\n", errno))
-               goto out;
-
-       CHECK(dst_cookie != src_cookie, "cookie mismatch", "%llu != %llu\n",
-             dst_cookie, src_cookie);
+       compare_cookies(skel->maps.src, dst_map);
 
 out:
        test_sockmap_update__destroy(skel);
-- 
2.25.1