Commit 6b9e3331 authored by Yonghong Song's avatar Yonghong Song Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add arraymap test for bpf_for_each_map_elem() helper 



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 45
    #45/1 hash_map:OK
    #45/2 array_map:OK
    #45 for_each:OK
    Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210226204934.3885756-1-yhs@fb.com
parent 9de7f0fd

tools/testing/selftests/bpf/prog_tests/for_each.c

+57 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
#include <test_progs.h>

#include <network_helpers.h>

#include "for_each_hash_map_elem.skel.h"

#include "for_each_array_map_elem.skel.h"



static unsigned int duration;
@@ -66,8 +67,64 @@ static void test_hash_map(void) 
	for_each_hash_map_elem__destroy(skel);

}



static void test_array_map(void)

{

	__u32 key, num_cpus, max_entries, retval;

	int i, arraymap_fd, percpu_map_fd, err;

	struct for_each_array_map_elem *skel;

	__u64 *percpu_valbuf = NULL;

	__u64 val, expected_total;



	skel = for_each_array_map_elem__open_and_load();

	if (!ASSERT_OK_PTR(skel, "for_each_array_map_elem__open_and_load"))

		return;



	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 (!ASSERT_OK(err, "map_update"))

			goto out;

	}



	num_cpus = bpf_num_possible_cpus();

	percpu_map_fd = bpf_map__fd(skel->maps.percpu_map);

	percpu_valbuf = malloc(sizeof(__u64) * num_cpus);

	if (!ASSERT_OK_PTR(percpu_valbuf, "percpu_valbuf"))

		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 (!ASSERT_OK(err, "percpu_map_update"))

		goto out;



	err = bpf_prog_test_run(bpf_program__fd(skel->progs.test_pkt_access),

				1, &pkt_v4, sizeof(pkt_v4), NULL, NULL,

				&retval, &duration);

	if (CHECK(err || retval, "ipv4", "err %d errno %d retval %d\n",

		  err, errno, retval))

		goto out;



	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);

}



void test_for_each(void)

{

	if (test__start_subtest("hash_map"))

		test_hash_map();

	if (test__start_subtest("array_map"))

		test_array_map();

}

tools/testing/selftests/bpf/progs/for_each_array_map_elem.c

0 → 100644
+61 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2021 Facebook */

#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_PERCPU_ARRAY);

	__uint(max_entries, 1);

	__type(key, __u32);

	__type(value, __u64);

} percpu_map SEC(".maps");



struct callback_ctx {

	int output;

};



static __u64

check_array_elem(struct bpf_map *map, __u32 *key, __u64 *val,

		 struct callback_ctx *data)

{

	data->output += *val;

	if (*key == 1)

		return 1; /* stop the iteration */

	return 0;

}



__u32 cpu = 0;

__u64 percpu_val = 0;



static __u64

check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val,

		  struct callback_ctx *data)

{

	cpu = bpf_get_smp_processor_id();

	percpu_val = *val;

	return 0;

}



u32 arraymap_output = 0;



SEC("classifier")

int test_pkt_access(struct __sk_buff *skb)

{

	struct callback_ctx data;



	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, (void *)0, 0);

	return 0;

}