Commit 60dd49ea authored by Yonghong Song's avatar Yonghong Song Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add test for bpf array map iterators 



Two subtests are added.
  $ ./test_progs -n 4
  ...
  #4/20 bpf_array_map:OK
  #4/21 bpf_percpu_array_map:OK
  ...

The bpf_array_map subtest also tested bpf program
changing array element values and send key/value
to user space through bpf_seq_write() interface.

Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184121.591367-1-yhs@fb.com
parent 2a7c2fff

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

+161 −0
Original line number Diff line number Diff line
@@ -17,6 +17,8 @@ 
#include "bpf_iter_test_kern4.skel.h"

#include "bpf_iter_bpf_hash_map.skel.h"

#include "bpf_iter_bpf_percpu_hash_map.skel.h"

#include "bpf_iter_bpf_array_map.skel.h"

#include "bpf_iter_bpf_percpu_array_map.skel.h"



static int duration;
@@ -638,6 +640,161 @@ static void test_bpf_percpu_hash_map(void) 
	bpf_iter_bpf_percpu_hash_map__destroy(skel);

}



static void test_bpf_array_map(void)

{

	__u64 val, expected_val = 0, res_first_val, first_val = 0;

	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);

	__u32 expected_key = 0, res_first_key;

	struct bpf_iter_bpf_array_map *skel;

	int err, i, map_fd, iter_fd;

	struct bpf_link *link;

	char buf[64] = {};

	int len, start;



	skel = bpf_iter_bpf_array_map__open_and_load();

	if (CHECK(!skel, "bpf_iter_bpf_array_map__open_and_load",

		  "skeleton open_and_load failed\n"))

		return;



	map_fd = bpf_map__fd(skel->maps.arraymap1);

	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {

		val = i + 4;

		expected_key += i;

		expected_val += val;



		if (i == 0)

			first_val = val;



		err = bpf_map_update_elem(map_fd, &i, &val, BPF_ANY);

		if (CHECK(err, "map_update", "map_update failed\n"))

			goto out;

	}



	opts.map_fd = map_fd;

	link = bpf_program__attach_iter(skel->progs.dump_bpf_array_map, &opts);

	if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n"))

		goto out;



	iter_fd = bpf_iter_create(bpf_link__fd(link));

	if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n"))

		goto free_link;



	/* do some tests */

	start = 0;

	while ((len = read(iter_fd, buf + start, sizeof(buf) - start)) > 0)

		start += len;

	if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno)))

		goto close_iter;



	/* test results */

	res_first_key = *(__u32 *)buf;

	res_first_val = *(__u64 *)(buf + sizeof(__u32));

	if (CHECK(res_first_key != 0 || res_first_val != first_val,

		  "bpf_seq_write",

		  "seq_write failure: first key %u vs expected 0, "

		  " first value %llu vs expected %llu\n",

		  res_first_key, res_first_val, first_val))

		goto close_iter;



	if (CHECK(skel->bss->key_sum != expected_key,

		  "key_sum", "got %u expected %u\n",

		  skel->bss->key_sum, expected_key))

		goto close_iter;

	if (CHECK(skel->bss->val_sum != expected_val,

		  "val_sum", "got %llu expected %llu\n",

		  skel->bss->val_sum, expected_val))

		goto close_iter;



	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {

		err = bpf_map_lookup_elem(map_fd, &i, &val);

		if (CHECK(err, "map_lookup", "map_lookup failed\n"))

			goto out;

		if (CHECK(i != val, "invalid_val",

			  "got value %llu expected %u\n", val, i))

			goto out;

	}



close_iter:

	close(iter_fd);

free_link:

	bpf_link__destroy(link);

out:

	bpf_iter_bpf_array_map__destroy(skel);

}



static void test_bpf_percpu_array_map(void)

{

	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);

	struct bpf_iter_bpf_percpu_array_map *skel;

	__u32 expected_key = 0, expected_val = 0;

	int err, i, j, map_fd, iter_fd;

	struct bpf_link *link;

	char buf[64];

	void *val;

	int len;



	val = malloc(8 * bpf_num_possible_cpus());



	skel = bpf_iter_bpf_percpu_array_map__open();

	if (CHECK(!skel, "bpf_iter_bpf_percpu_array_map__open",

		  "skeleton open failed\n"))

		return;



	skel->rodata->num_cpus = bpf_num_possible_cpus();



	err = bpf_iter_bpf_percpu_array_map__load(skel);

	if (CHECK(!skel, "bpf_iter_bpf_percpu_array_map__load",

		  "skeleton load failed\n"))

		goto out;



	/* update map values here */

	map_fd = bpf_map__fd(skel->maps.arraymap1);

	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {

		expected_key += i;



		for (j = 0; j < bpf_num_possible_cpus(); j++) {

			*(__u32 *)(val + j * 8) = i + j;

			expected_val += i + j;

		}



		err = bpf_map_update_elem(map_fd, &i, val, BPF_ANY);

		if (CHECK(err, "map_update", "map_update failed\n"))

			goto out;

	}



	opts.map_fd = map_fd;

	link = bpf_program__attach_iter(skel->progs.dump_bpf_percpu_array_map, &opts);

	if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n"))

		goto out;



	iter_fd = bpf_iter_create(bpf_link__fd(link));

	if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n"))

		goto free_link;



	/* do some tests */

	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)

		;

	if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno)))

		goto close_iter;



	/* test results */

	if (CHECK(skel->bss->key_sum != expected_key,

		  "key_sum", "got %u expected %u\n",

		  skel->bss->key_sum, expected_key))

		goto close_iter;

	if (CHECK(skel->bss->val_sum != expected_val,

		  "val_sum", "got %u expected %u\n",

		  skel->bss->val_sum, expected_val))

		goto close_iter;



close_iter:

	close(iter_fd);

free_link:

	bpf_link__destroy(link);

out:

	bpf_iter_bpf_percpu_array_map__destroy(skel);

}



void test_bpf_iter(void)

{

	if (test__start_subtest("btf_id_or_null"))
@@ -678,4 +835,8 @@ void test_bpf_iter(void) 
		test_bpf_hash_map();

	if (test__start_subtest("bpf_percpu_hash_map"))

		test_bpf_percpu_hash_map();

	if (test__start_subtest("bpf_array_map"))

		test_bpf_array_map();

	if (test__start_subtest("bpf_percpu_array_map"))

		test_bpf_percpu_array_map();

}

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

0 → 100644
+40 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2020 Facebook */

#include "bpf_iter.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



char _license[] SEC("license") = "GPL";



struct key_t {

	int a;

	int b;

	int c;

};



struct {

	__uint(type, BPF_MAP_TYPE_ARRAY);

	__uint(max_entries, 3);

	__type(key, __u32);

	__type(value, __u64);

} arraymap1 SEC(".maps");



__u32 key_sum = 0;

__u64 val_sum = 0;



SEC("iter/bpf_map_elem")

int dump_bpf_array_map(struct bpf_iter__bpf_map_elem *ctx)

{

	__u32 *key = ctx->key;

	__u64 *val = ctx->value;



	if (key == (void *)0 || val == (void *)0)

		return 0;



	bpf_seq_write(ctx->meta->seq, key, sizeof(__u32));

	bpf_seq_write(ctx->meta->seq, val, sizeof(__u64));

	key_sum += *key;

	val_sum += *val;

	*val = *key;

	return 0;

}

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

0 → 100644
+46 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2020 Facebook */

#include "bpf_iter.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



char _license[] SEC("license") = "GPL";



struct key_t {

	int a;

	int b;

	int c;

};



struct {

	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);

	__uint(max_entries, 3);

	__type(key, __u32);

	__type(value, __u32);

} arraymap1 SEC(".maps");



/* will set before prog run */

volatile const __u32 num_cpus = 0;



__u32 key_sum = 0, val_sum = 0;



SEC("iter/bpf_map_elem")

int dump_bpf_percpu_array_map(struct bpf_iter__bpf_map_elem *ctx)

{

	__u32 *key = ctx->key;

	void *pptr = ctx->value;

	__u32 step;

	int i;



	if (key == (void *)0 || pptr == (void *)0)

		return 0;



	key_sum += *key;



	step = 8;

	for (i = 0; i < num_cpus; i++) {

		val_sum += *(__u32 *)pptr;

		pptr += step;

	}

	return 0;

}