samples/bpf: add bpf_map_update_elem() tests

increase test coverage to check previously missing 'update when full'

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/samples/bpf/test_maps.c b/samples/bpf/test_maps.c
index 47bf085..cce2b59 100644 (file)
--- a/samples/bpf/test_maps.c
+++ b/samples/bpf/test_maps.c
@@ -68,7 +68,16 @@ static void test_hashmap_sanity(int i, void *data)
        assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
               errno == E2BIG);
 
+       /* update existing element, thought the map is full */
+       key = 1;
+       assert(bpf_update_elem(map_fd, &key, &value, BPF_EXIST) == 0);
+       key = 2;
+       assert(bpf_update_elem(map_fd, &key, &value, BPF_ANY) == 0);
+       key = 1;
+       assert(bpf_update_elem(map_fd, &key, &value, BPF_ANY) == 0);
+
        /* check that key = 0 doesn't exist */
+       key = 0;
        assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
 
        /* iterate over two elements */
@@ -413,10 +422,12 @@ static void do_work(int fn, void *data)
 
        for (i = fn; i < MAP_SIZE; i += TASKS) {
                key = value = i;
-               if (do_update)
+               if (do_update) {
                        assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == 0);
-               else
+                       assert(bpf_update_elem(map_fd, &key, &value, BPF_EXIST) == 0);
+               } else {
                        assert(bpf_delete_elem(map_fd, &key) == 0);
+               }
        }
 }