On Thu, Feb 4, 2021 at 5:53 PM Yonghong Song <yhs@xxxxxx> wrote:
>
> A test is added for arraymap and percpu arraymap. The test also
> exercises the early return for the helper which does not
> traverse all elements.
> $ ./test_progs -n 44
> #44/1 hash_map:OK
> #44/2 array_map:OK
> #44 for_each:OK
> Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED
>
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> ---
> .../selftests/bpf/prog_tests/for_each.c | 54 ++++++++++++++
> .../bpf/progs/for_each_array_map_elem.c | 71 +++++++++++++++++++
> 2 files changed, 125 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/progs/for_each_array_map_elem.c
>
[...]
> +
> + arraymap_fd = bpf_map__fd(skel->maps.arraymap);
> + expected_total = 0;
> + max_entries = bpf_map__max_entries(skel->maps.arraymap);
> + for (i = 0; i < max_entries; i++) {
> + key = i;
> + val = i + 1;
> + /* skip the last iteration for expected total */
> + if (i != max_entries - 1)
> + expected_total += val;
> + err = bpf_map_update_elem(arraymap_fd, &key, &val, BPF_ANY);
> + if (CHECK(err, "map_update", "map_update failed\n"))
> + goto out;
> + }
> +
> + num_cpus = bpf_num_possible_cpus();
> + percpu_map_fd = bpf_map__fd(skel->maps.percpu_map);
formatting is off, please check with checkfile.pl
> + percpu_valbuf = malloc(sizeof(__u64) * num_cpus);
> + if (CHECK_FAIL(!percpu_valbuf))
please don't use CHECK_FAIL, ASSERT_PTR_OK would work nicely here
> + goto out;
> +
> + key = 0;
> + for (i = 0; i < num_cpus; i++)
> + percpu_valbuf[i] = i + 1;
> + err = bpf_map_update_elem(percpu_map_fd, &key, percpu_valbuf, BPF_ANY);
> + if (CHECK(err, "percpu_map_update", "map_update failed\n"))
> + goto out;
> +
> + do_dummy_read(skel->progs.dump_task);
see previous patch, iter/tasks seems like an overkill for these tests
> +
> + ASSERT_EQ(skel->bss->called, 1, "called");
> + ASSERT_EQ(skel->bss->arraymap_output, expected_total, "array_output");
> + ASSERT_EQ(skel->bss->cpu + 1, skel->bss->percpu_val, "percpu_val");
> +
> +out:
> + free(percpu_valbuf);
> + for_each_array_map_elem__destroy(skel);
> +}
> +
[...]
> +SEC("iter/task")
> +int dump_task(struct bpf_iter__task *ctx)
> +{
> + struct seq_file *seq = ctx->meta->seq;
> + struct task_struct *task = ctx->task;
> + struct callback_ctx data;
> +
> + /* only call once */
> + if (called > 0)
> + return 0;
> +
> + called++;
> +
> + data.output = 0;
> + bpf_for_each_map_elem(&arraymap, check_array_elem, &data, 0);
> + arraymap_output = data.output;
> +
> + bpf_for_each_map_elem(&percpu_map, check_percpu_elem, 0, 0);
nit: NULL, 0 ?
> +
> + return 0;
> +}
> --
> 2.24.1
>
