selftests/bpf: add test for bpf_for_each_map_elem() with different maps

A test is added for bpf_for_each_map_elem() with either an arraymap or a
hashmap.
$ tools/testing/selftests/bpf/test_progs -t for_each
 #93/1    for_each/hash_map:OK
 #93/2    for_each/array_map:OK
 #93/3    for_each/write_map_key:OK
 #93/4    for_each/multi_maps:OK
 #93      for_each:OK
Summary: 1/4 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240405025536.18113-4-lulie@linux.alibaba.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/for_each.c b/tools/testing/selftests/bpf/prog_tests/for_each.c
index 8963f8a549f2aa2053ce2a613772a991b757546b..09f6487f58b9cb6c88b78ed3bb3191d0d414505a 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/for_each.c
+++ b/tools/testing/selftests/bpf/prog_tests/for_each.c
@@ -5,6 +5,7 @@
 #include "for_each_hash_map_elem.skel.h"
 #include "for_each_array_map_elem.skel.h"
 #include "for_each_map_elem_write_key.skel.h"
+#include "for_each_multi_maps.skel.h"
 
 static unsigned int duration;
 
@@ -143,6 +144,65 @@ static void test_write_map_key(void)
                for_each_map_elem_write_key__destroy(skel);
 }
 
+static void test_multi_maps(void)
+{
+       struct for_each_multi_maps *skel;
+       __u64 val, array_total, hash_total;
+       __u32 key, max_entries;
+       int i, err;
+
+       LIBBPF_OPTS(bpf_test_run_opts, topts,
+               .data_in = &pkt_v4,
+               .data_size_in = sizeof(pkt_v4),
+               .repeat = 1,
+       );
+
+       skel = for_each_multi_maps__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "for_each_multi_maps__open_and_load"))
+               return;
+
+       array_total = 0;
+       max_entries = bpf_map__max_entries(skel->maps.arraymap);
+       for (i = 0; i < max_entries; i++) {
+               key = i;
+               val = i + 1;
+               array_total += val;
+               err = bpf_map__update_elem(skel->maps.arraymap, &key, sizeof(key),
+                                          &val, sizeof(val), BPF_ANY);
+               if (!ASSERT_OK(err, "array_map_update"))
+                       goto out;
+       }
+
+       hash_total = 0;
+       max_entries = bpf_map__max_entries(skel->maps.hashmap);
+       for (i = 0; i < max_entries; i++) {
+               key = i + 100;
+               val = i + 1;
+               hash_total += val;
+               err = bpf_map__update_elem(skel->maps.hashmap, &key, sizeof(key),
+                                          &val, sizeof(val), BPF_ANY);
+               if (!ASSERT_OK(err, "hash_map_update"))
+                       goto out;
+       }
+
+       skel->bss->data_output = 0;
+       skel->bss->use_array = 1;
+       err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_pkt_access), &topts);
+       ASSERT_OK(err, "bpf_prog_test_run_opts");
+       ASSERT_OK(topts.retval, "retval");
+       ASSERT_EQ(skel->bss->data_output, array_total, "array output");
+
+       skel->bss->data_output = 0;
+       skel->bss->use_array = 0;
+       err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_pkt_access), &topts);
+       ASSERT_OK(err, "bpf_prog_test_run_opts");
+       ASSERT_OK(topts.retval, "retval");
+       ASSERT_EQ(skel->bss->data_output, hash_total, "hash output");
+
+out:
+       for_each_multi_maps__destroy(skel);
+}
+
 void test_for_each(void)
 {
        if (test__start_subtest("hash_map"))
@@ -151,4 +211,6 @@ void test_for_each(void)
                test_array_map();
        if (test__start_subtest("write_map_key"))
                test_write_map_key();
+       if (test__start_subtest("multi_maps"))
+               test_multi_maps();
 }

diff --git a/tools/testing/selftests/bpf/progs/for_each_multi_maps.c b/tools/testing/selftests/bpf/progs/for_each_multi_maps.c
new file mode 100644 (file)
index 0000000..ff0bed7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/for_each_multi_maps.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+struct {
+       __uint(type, BPF_MAP_TYPE_ARRAY);
+       __uint(max_entries, 3);
+       __type(key, __u32);
+       __type(value, __u64);
+} arraymap SEC(".maps");
+
+struct {
+       __uint(type, BPF_MAP_TYPE_HASH);
+       __uint(max_entries, 5);
+       __type(key, __u32);
+       __type(value, __u64);
+} hashmap SEC(".maps");
+
+struct callback_ctx {
+       int output;
+};
+
+u32 data_output = 0;
+int use_array = 0;
+
+static __u64
+check_map_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+              struct callback_ctx *data)
+{
+       data->output += *val;
+       return 0;
+}
+
+SEC("tc")
+int test_pkt_access(struct __sk_buff *skb)
+{
+       struct callback_ctx data;
+
+       data.output = 0;
+       if (use_array)
+               bpf_for_each_map_elem(&arraymap, check_map_elem, &data, 0);
+       else
+               bpf_for_each_map_elem(&hashmap, check_map_elem, &data, 0);
+       data_output = data.output;
+
+       return 0;
+}