Commit e1559671 authored by Martin KaFai Lau's avatar Martin KaFai Lau Committed by David S. Miller
Browse files

samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_HASH 



A sanity test for BPF_MAP_TYPE_PERCPU_HASH.

Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 15a07b33

samples/bpf/test_maps.c

+96 −0
Original line number Diff line number Diff line
@@ -89,6 +89,100 @@ static void test_hashmap_sanity(int i, void *data) 
	close(map_fd);

}



/* sanity tests for percpu map API */

static void test_percpu_hashmap_sanity(int task, void *data)

{

	long long key, next_key;

	int expected_key_mask = 0;

	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);

	long long value[nr_cpus];

	int map_fd, i;



	map_fd = bpf_create_map(BPF_MAP_TYPE_PERCPU_HASH, sizeof(key),

				sizeof(value[0]), 2);

	if (map_fd < 0) {

		printf("failed to create hashmap '%s'\n", strerror(errno));

		exit(1);

	}



	for (i = 0; i < nr_cpus; i++)

		value[i] = i + 100;

	key = 1;

	/* insert key=1 element */

	assert(!(expected_key_mask & key));

	assert(bpf_update_elem(map_fd, &key, value, BPF_ANY) == 0);

	expected_key_mask |= key;



	/* BPF_NOEXIST means: add new element if it doesn't exist */

	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == -1 &&

	       /* key=1 already exists */

	       errno == EEXIST);



	/* -1 is an invalid flag */

	assert(bpf_update_elem(map_fd, &key, value, -1) == -1 &&

	       errno == EINVAL);



	/* check that key=1 can be found. value could be 0 if the lookup

	 * was run from a different cpu.

	 */

	value[0] = 1;

	assert(bpf_lookup_elem(map_fd, &key, value) == 0 && value[0] == 100);



	key = 2;

	/* check that key=2 is not found */

	assert(bpf_lookup_elem(map_fd, &key, value) == -1 && errno == ENOENT);



	/* BPF_EXIST means: update existing element */

	assert(bpf_update_elem(map_fd, &key, value, BPF_EXIST) == -1 &&

	       /* key=2 is not there */

	       errno == ENOENT);



	/* insert key=2 element */

	assert(!(expected_key_mask & key));

	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == 0);

	expected_key_mask |= key;



	/* key=1 and key=2 were inserted, check that key=0 cannot be inserted

	 * due to max_entries limit

	 */

	key = 0;

	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == -1 &&

	       errno == E2BIG);



	/* check that key = 0 doesn't exist */

	assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);



	/* iterate over two elements */

	while (!bpf_get_next_key(map_fd, &key, &next_key)) {

		assert((expected_key_mask & next_key) == next_key);

		expected_key_mask &= ~next_key;



		assert(bpf_lookup_elem(map_fd, &next_key, value) == 0);

		for (i = 0; i < nr_cpus; i++)

			assert(value[i] == i + 100);



		key = next_key;

	}

	assert(errno == ENOENT);



	/* Update with BPF_EXIST */

	key = 1;

	assert(bpf_update_elem(map_fd, &key, value, BPF_EXIST) == 0);



	/* delete both elements */

	key = 1;

	assert(bpf_delete_elem(map_fd, &key) == 0);

	key = 2;

	assert(bpf_delete_elem(map_fd, &key) == 0);

	assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);



	key = 0;

	/* check that map is empty */

	assert(bpf_get_next_key(map_fd, &key, &next_key) == -1 &&

	       errno == ENOENT);

	close(map_fd);

}



static void test_arraymap_sanity(int i, void *data)

{

	int key, next_key, map_fd;
@@ -209,6 +303,7 @@ static void run_parallel(int tasks, void (*fn)(int i, void *data), void *data) 
static void test_map_stress(void)

{

	run_parallel(100, test_hashmap_sanity, NULL);

	run_parallel(100, test_percpu_hashmap_sanity, NULL);

	run_parallel(100, test_arraymap_sanity, NULL);

}
@@ -282,6 +377,7 @@ static void test_map_parallel(void) 
int main(void)

{

	test_hashmap_sanity(0, NULL);

	test_percpu_hashmap_sanity(0, NULL);

	test_arraymap_sanity(0, NULL);

	test_map_large();

	test_map_parallel();