selftests/bpf: Test for associating multiple elements with the local storage

This patch adds a few calls to the existing local storage selftest to
test that we can associate multiple elements with the local storage.

The sleepable program's call to bpf_sk_storage_get with sk_storage_map2
will lead to an allocation of a new selem under the GFP_KERNEL flag.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220318045553.3091807-3-joannekoong@fb.com

diff --git a/tools/testing/selftests/bpf/progs/local_storage.c b/tools/testing/selftests/bpf/progs/local_storage.c
index 9b1f9b7..19423ed 100644 (file)
--- a/tools/testing/selftests/bpf/progs/local_storage.c
+++ b/tools/testing/selftests/bpf/progs/local_storage.c
@@ -36,6 +36,13 @@ struct {
        __type(value, struct local_storage);
 } sk_storage_map SEC(".maps");
 
+struct {
+       __uint(type, BPF_MAP_TYPE_SK_STORAGE);
+       __uint(map_flags, BPF_F_NO_PREALLOC | BPF_F_CLONE);
+       __type(key, int);
+       __type(value, struct local_storage);
+} sk_storage_map2 SEC(".maps");
+
 struct {
        __uint(type, BPF_MAP_TYPE_TASK_STORAGE);
        __uint(map_flags, BPF_F_NO_PREALLOC);
@@ -115,7 +122,19 @@ int BPF_PROG(socket_bind, struct socket *sock, struct sockaddr *address,
        if (storage->value != DUMMY_STORAGE_VALUE)
                sk_storage_result = -1;
 
+       /* This tests that we can associate multiple elements
+        * with the local storage.
+        */
+       storage = bpf_sk_storage_get(&sk_storage_map2, sock->sk, 0,
+                                    BPF_LOCAL_STORAGE_GET_F_CREATE);
+       if (!storage)
+               return 0;
+
        err = bpf_sk_storage_delete(&sk_storage_map, sock->sk);
+       if (err)
+               return 0;
+
+       err = bpf_sk_storage_delete(&sk_storage_map2, sock->sk);
        if (!err)
                sk_storage_result = err;