[PATCH v4 bpf-next 8/9] selftests/bpf: add batch ops testing for htab and htab_percpu map

From: Brian Vazquez
Date: Tue Jan 14 2020 - 11:47:14 EST


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 | 285 ++++++++++++++++++
1 file changed, 285 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..670d7e6574899
--- /dev/null
+++ b/tools/testing/selftests/bpf/map_tests/htab_map_batch_ops.c
@@ -0,0 +1,285 @@
+// 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);
+ value *v = NULL;
+ int i, j, err;
+
+ DECLARE_LIBBPF_OPTS(bpf_map_batch_opts, opts,
+ .elem_flags = 0,
+ .flags = 0,
+ );
+
+ 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, &opts);
+ 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 = NULL;
+ 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[max_entries];
+ bool nospace_err;
+ void *values;
+
+ DECLARE_LIBBPF_OPTS(bpf_map_batch_opts, opts,
+ .elem_flags = 0,
+ .flags = 0,
+ );
+
+ 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));
+
+ /* 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, &opts);
+ 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, &opts);
+ 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, &opts);
+ 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));
+
+ /* test 4: lookup/delete in a loop with various steps. */
+ total_success = 0;
+ for (step = 1; step < max_entries; step++) {
+ map_batch_update(map_fd, max_entries, keys, values, is_pcpu);
+ memset(keys, 0, max_entries * sizeof(*keys));
+ memset(values, 0, max_entries * value_size);
+ total = 0;
+ /* iteratively lookup/delete elements with 'step'
+ * elements each
+ */
+ count = step;
+ nospace_err = false;
+ while (true) {
+ err = bpf_map_lookup_batch(map_fd,
+ total ? &batch : NULL,
+ &batch, keys + total,
+ values +
+ total * value_size,
+ &count, &opts);
+ /* It is possible that we are failing due to buffer size
+ * not big enough. In such cases, let us just exit and
+ * go with large steps. Not that a buffer size with
+ * max_entries should always work.
+ */
+ if (err && errno == ENOSPC) {
+ nospace_err = true;
+ break;
+ }
+
+ CHECK((err && errno != ENOENT), "lookup with steps",
+ "error: %s\n", strerror(errno));
+
+ total += count;
+ if (err)
+ break;
+
+ }
+ if (nospace_err == true)
+ continue;
+
+ CHECK(total != max_entries, "lookup with steps",
+ "total = %u, max_entries = %u\n", total, max_entries);
+ map_batch_verify(visited, max_entries, keys, values, is_pcpu);
+
+ total = 0;
+ count = step;
+ while (total < max_entries) {
+ if (max_entries - total < step)
+ count = max_entries - total;
+ err = bpf_map_delete_batch(map_fd,
+ keys + total,
+ &count, &opts);
+ CHECK((err && errno != ENOENT), "delete batch",
+ "error: %s\n", strerror(errno));
+ total += count;
+ if (err)
+ break;
+ }
+ CHECK(total != max_entries, "delete with steps",
+ "total = %u, max_entries = %u\n", total, max_entries);
+
+ /* check map is empty, errono == ENOENT */
+ err = bpf_map_get_next_key(map_fd, NULL, &key);
+ CHECK(!err || errno != ENOENT, "bpf_map_get_next_key()",
+ "error: %s\n", strerror(errno));
+
+ /* iteratively lookup/delete elements with 'step'
+ * elements each
+ */
+ map_batch_update(map_fd, max_entries, keys, values, is_pcpu);
+ memset(keys, 0, max_entries * sizeof(*keys));
+ memset(values, 0, max_entries * value_size);
+ total = 0;
+ count = step;
+ nospace_err = false;
+ while (true) {
+ err = bpf_map_lookup_and_delete_batch(map_fd,
+ total ? &batch : NULL,
+ &batch, keys + total,
+ values +
+ total * value_size,
+ &count, &opts);
+ /* It is possible that we are failing due to buffer size
+ * not big enough. In such cases, let us just exit and
+ * go with large steps. Not that a buffer size with
+ * max_entries should always work.
+ */
+ if (err && errno == ENOSPC) {
+ nospace_err = true;
+ break;
+ }
+
+ CHECK((err && errno != ENOENT), "lookup with steps",
+ "error: %s\n", strerror(errno));
+
+ total += count;
+ if (err)
+ break;
+ }
+
+ if (nospace_err == true)
+ continue;
+
+ CHECK(total != max_entries, "lookup/delete with steps",
+ "total = %u, max_entries = %u\n", total, max_entries);
+
+ map_batch_verify(visited, max_entries, keys, values, is_pcpu);
+ err = bpf_map_get_next_key(map_fd, NULL, &key);
+ CHECK(!err, "bpf_map_get_next_key()", "error: %s\n",
+ strerror(errno));
+
+ total_success++;
+ }
+
+ CHECK(total_success == 0, "check total_success",
+ "unexpected failure\n");
+ free(keys);
+ free(visited);
+ if (!is_pcpu)
+ free(values);
+}
+
+void htab_map_batch_ops(void)
+{
+ __test_map_lookup_and_delete_batch(false);
+ printf("test_%s:PASS\n", __func__);
+}
+
+void htab_percpu_map_batch_ops(void)
+{
+ __test_map_lookup_and_delete_batch(true);
+ printf("test_%s:PASS\n", __func__);
+}
+
+void test_htab_map_batch_ops(void)
+{
+ htab_map_batch_ops();
+ htab_percpu_map_batch_ops();
+}
--
2.25.0.rc1.283.g88dfdc4193-goog