Re: [PATCH v3 bpf-next 09/11] selftests/bpf: add batch ops testing for htab and htab_percpu map

[Yonghong Song]

On 12/11/19 2:33 PM, Brian Vazquez wrote:
> From: Yonghong Song <yhs@xxxxxx>
> 
> Tested bpf_map_lookup_batch(), bpf_map_lookup_and_delete_batch(),
> bpf_map_update_batch(), and bpf_map_delete_batch() functionality.
>    $ ./test_maps
>      ...
>        test_htab_map_batch_ops:PASS
>        test_htab_percpu_map_batch_ops:PASS
>      ...
> 
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> Signed-off-by: Brian Vazquez <brianvv@xxxxxxxxxx>
> ---
>   .../bpf/map_tests/htab_map_batch_ops.c        | 269 ++++++++++++++++++
>   1 file changed, 269 insertions(+)
>   create mode 100644 tools/testing/selftests/bpf/map_tests/htab_map_batch_ops.c
> 
> diff --git a/tools/testing/selftests/bpf/map_tests/htab_map_batch_ops.c b/tools/testing/selftests/bpf/map_tests/htab_map_batch_ops.c
> new file mode 100644
> index 0000000000000..dabc4d420a10e
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/map_tests/htab_map_batch_ops.c
> @@ -0,0 +1,269 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2019 Facebook  */
> +#include <stdio.h>
> +#include <errno.h>
> +#include <string.h>
> +
> +#include <bpf/bpf.h>
> +#include <bpf/libbpf.h>
> +
> +#include <bpf_util.h>
> +#include <test_maps.h>
> +
> +static void map_batch_update(int map_fd, __u32 max_entries, int *keys,
> +			     void *values, bool is_pcpu)
> +{
> +	typedef BPF_DECLARE_PERCPU(int, value);
> +	int i, j, err;
> +	value *v;
> +
> +	if (is_pcpu)
> +		v = (value *)values;
> +
> +	for (i = 0; i < max_entries; i++) {
> +		keys[i] = i + 1;
> +		if (is_pcpu)
> +			for (j = 0; j < bpf_num_possible_cpus(); j++)
> +				bpf_percpu(v[i], j) = i + 2 + j;
> +		else
> +			((int *)values)[i] = i + 2;
> +	}
> +
> +	err = bpf_map_update_batch(map_fd, keys, values, &max_entries, 0, 0);
> +	CHECK(err, "bpf_map_update_batch()", "error:%s\n", strerror(errno));
> +}
> +
> +static void map_batch_verify(int *visited, __u32 max_entries,
> +			     int *keys, void *values, bool is_pcpu)
> +{
> +	typedef BPF_DECLARE_PERCPU(int, value);
> +	value *v;
> +	int i, j;
> +
> +	if (is_pcpu)
> +		v = (value *)values;
> +
> +	memset(visited, 0, max_entries * sizeof(*visited));
> +	for (i = 0; i < max_entries; i++) {
> +
> +		if (is_pcpu) {
> +			for (j = 0; j < bpf_num_possible_cpus(); j++) {
> +				CHECK(keys[i] + 1 + j != bpf_percpu(v[i], j),
> +				      "key/value checking",
> +				      "error: i %d j %d key %d value %d\n",
> +				      i, j, keys[i], bpf_percpu(v[i],  j));
> +			}
> +		} else {
> +			CHECK(keys[i] + 1 != ((int *)values)[i],
> +			      "key/value checking",
> +			      "error: i %d key %d value %d\n", i, keys[i],
> +			      ((int *)values)[i]);
> +		}
> +
> +		visited[i] = 1;
> +
> +	}
> +	for (i = 0; i < max_entries; i++) {
> +		CHECK(visited[i] != 1, "visited checking",
> +		      "error: keys array at index %d missing\n", i);
> +	}
> +}
> +
> +void __test_map_lookup_and_delete_batch(bool is_pcpu)
> +{
> +	int map_type = is_pcpu ? BPF_MAP_TYPE_PERCPU_HASH : BPF_MAP_TYPE_HASH;
> +	struct bpf_create_map_attr xattr = {
> +		.name = "hash_map",
> +		.map_type = map_type,
> +		.key_size = sizeof(int),
> +		.value_size = sizeof(int),
> +	};
> +	__u32 batch, count, total, total_success;
> +	typedef BPF_DECLARE_PERCPU(int, value);
> +	int map_fd, *keys, *visited, key;
> +	const __u32 max_entries = 10;
> +	int err, step, value_size;
> +	value pcpu_values[10];
> +	bool nospace_err;
> +	void *values;
> +
> +	xattr.max_entries = max_entries;
> +	map_fd = bpf_create_map_xattr(&xattr);
> +	CHECK(map_fd == -1,
> +	      "bpf_create_map_xattr()", "error:%s\n", strerror(errno));
> +
> +	value_size = is_pcpu ? sizeof(value) : sizeof(int);
> +	keys = malloc(max_entries * sizeof(int));
> +	if (is_pcpu)
> +		values = pcpu_values;
> +	else
> +		values = malloc(max_entries * sizeof(int));
> +	visited = malloc(max_entries * sizeof(int));
> +	CHECK(!keys || !values || !visited, "malloc()",
> +	      "error:%s\n", strerror(errno));

Sorry, I missed it. the mallcoed keys/visited memory region should
be freed at the end of the test. The same for other tests.

> +
> +	/* test 1: lookup/delete an empty hash table, -ENOENT */
> +	count = max_entries;
> +	err = bpf_map_lookup_and_delete_batch(map_fd, NULL, &batch, keys,
> +					      values, &count, 0, 0);
> +	CHECK((err && errno != ENOENT), "empty map",
> +	      "error: %s\n", strerror(errno));
> +
> +	/* populate elements to the map */
> +	map_batch_update(map_fd, max_entries, keys, values, is_pcpu);
> +
> +	/* test 2: lookup/delete with count = 0, success */
> +	count = 0;
> +	err = bpf_map_lookup_and_delete_batch(map_fd, NULL, &batch, keys,
> +					      values, &count, 0, 0);
> +	CHECK(err, "count = 0", "error: %s\n", strerror(errno));
> +
> +	/* test 3: lookup/delete with count = max_entries, success */
> +	memset(keys, 0, max_entries * sizeof(*keys));
> +	memset(values, 0, max_entries * value_size);
> +	count = max_entries;
> +	err = bpf_map_lookup_and_delete_batch(map_fd, NULL, &batch, keys,
> +					      values, &count, 0, 0);
> +	CHECK((err && errno != ENOENT), "count = max_entries",
> +	       "error: %s\n", strerror(errno));
> +	CHECK(count != max_entries, "count = max_entries",
> +	      "count = %u, max_entries = %u\n", count, max_entries);
> +	map_batch_verify(visited, max_entries, keys, values, is_pcpu);
> +
> +	/* bpf_map_get_next_key() should return -ENOENT for an empty map. */
> +	err = bpf_map_get_next_key(map_fd, NULL, &key);
> +	CHECK(!err, "bpf_map_get_next_key()", "error: %s\n", strerror(errno));
> +
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