Iterating through array of maps may encounter non existing keys. The batch operation should not fail on when this happens.
Signed-off-by: Yan Zhai yan@cloudflare.com --- .../bpf/map_tests/map_in_map_batch_ops.c | 62 +++++++++++++------ 1 file changed, 44 insertions(+), 18 deletions(-)
diff --git a/tools/testing/selftests/bpf/map_tests/map_in_map_batch_ops.c b/tools/testing/selftests/bpf/map_tests/map_in_map_batch_ops.c index 66191ae9863c..79c3ccadb962 100644 --- a/tools/testing/selftests/bpf/map_tests/map_in_map_batch_ops.c +++ b/tools/testing/selftests/bpf/map_tests/map_in_map_batch_ops.c @@ -120,11 +120,12 @@ static void validate_fetch_results(int outer_map_fd,
static void fetch_and_validate(int outer_map_fd, struct bpf_map_batch_opts *opts, - __u32 batch_size, bool delete_entries) + __u32 batch_size, bool delete_entries, + bool has_holes) { - __u32 *fetched_keys, *fetched_values, total_fetched = 0; - __u32 batch_key = 0, fetch_count, step_size; - int err, max_entries = OUTER_MAP_ENTRIES; + int err, max_entries = OUTER_MAP_ENTRIES - !!has_holes; + __u32 *fetched_keys, *fetched_values, total_fetched = 0, i; + __u32 batch_key = 0, fetch_count, step_size = batch_size; __u32 value_size = sizeof(__u32);
/* Total entries needs to be fetched */ @@ -134,9 +135,8 @@ static void fetch_and_validate(int outer_map_fd, "Memory allocation failed for fetched_keys or fetched_values", "error=%s\n", strerror(errno));
- for (step_size = batch_size; - step_size <= max_entries; - step_size += batch_size) { + /* hash map may not always return full batch */ + for (i = 0; i < OUTER_MAP_ENTRIES; i++) { fetch_count = step_size; err = delete_entries ? bpf_map_lookup_and_delete_batch(outer_map_fd, @@ -155,6 +155,7 @@ static void fetch_and_validate(int outer_map_fd, if (err && errno == ENOSPC) { /* Fetch again with higher batch size */ total_fetched = 0; + step_size += batch_size; continue; }
@@ -184,18 +185,19 @@ static void fetch_and_validate(int outer_map_fd, }
static void _map_in_map_batch_ops(enum bpf_map_type outer_map_type, - enum bpf_map_type inner_map_type) + enum bpf_map_type inner_map_type, + bool has_holes) { + __u32 max_entries = OUTER_MAP_ENTRIES - !!has_holes; __u32 *outer_map_keys, *inner_map_fds; - __u32 max_entries = OUTER_MAP_ENTRIES; LIBBPF_OPTS(bpf_map_batch_opts, opts); __u32 value_size = sizeof(__u32); int batch_size[2] = {5, 10}; __u32 map_index, op_index; int outer_map_fd, ret;
- outer_map_keys = calloc(max_entries, value_size); - inner_map_fds = calloc(max_entries, value_size); + outer_map_keys = calloc(OUTER_MAP_ENTRIES, value_size); + inner_map_fds = calloc(OUTER_MAP_ENTRIES, value_size); CHECK((!outer_map_keys || !inner_map_fds), "Memory allocation failed for outer_map_keys or inner_map_fds", "error=%s\n", strerror(errno)); @@ -209,6 +211,24 @@ static void _map_in_map_batch_ops(enum bpf_map_type outer_map_type, ((outer_map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) ? 9 : 1000) - map_index;
+ /* This condition is only meaningful for array of maps. + * + * max_entries == OUTER_MAP_ENTRIES - 1 if it is true. Say + * max_entries is short for n, then outer_map_keys looks like: + * + * [n, n-1, ... 2, 1] + * + * We change it to + * + * [n, n-1, ... 2, 0] + * + * So it will leave key 1 as a hole. It will serve to test the + * correctness when batch on an array: a "non-exist" key might be + * actually allocated and returned from key iteration. + */ + if (has_holes) + outer_map_keys[max_entries - 1]--; + /* batch operation - map_update */ ret = bpf_map_update_batch(outer_map_fd, outer_map_keys, inner_map_fds, &max_entries, &opts); @@ -219,15 +239,17 @@ static void _map_in_map_batch_ops(enum bpf_map_type outer_map_type, /* batch operation - map_lookup */ for (op_index = 0; op_index < 2; ++op_index) fetch_and_validate(outer_map_fd, &opts, - batch_size[op_index], false); + batch_size[op_index], false, + has_holes);
/* batch operation - map_lookup_delete */ if (outer_map_type == BPF_MAP_TYPE_HASH_OF_MAPS) fetch_and_validate(outer_map_fd, &opts, - max_entries, true /*delete*/); + max_entries, true /*delete*/, + has_holes);
/* close all map fds */ - for (map_index = 0; map_index < max_entries; map_index++) + for (map_index = 0; map_index < OUTER_MAP_ENTRIES; map_index++) close(inner_map_fds[map_index]); close(outer_map_fd);
@@ -237,16 +259,20 @@ static void _map_in_map_batch_ops(enum bpf_map_type outer_map_type,
void test_map_in_map_batch_ops_array(void) { - _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_ARRAY); + _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_ARRAY, false); printf("%s:PASS with inner ARRAY map\n", __func__); - _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_HASH); + _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_HASH, false); printf("%s:PASS with inner HASH map\n", __func__); + _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_ARRAY, true); + printf("%s:PASS with inner ARRAY map with holes\n", __func__); + _map_in_map_batch_ops(BPF_MAP_TYPE_ARRAY_OF_MAPS, BPF_MAP_TYPE_HASH, true); + printf("%s:PASS with inner HASH map with holes\n", __func__); }
void test_map_in_map_batch_ops_hash(void) { - _map_in_map_batch_ops(BPF_MAP_TYPE_HASH_OF_MAPS, BPF_MAP_TYPE_ARRAY); + _map_in_map_batch_ops(BPF_MAP_TYPE_HASH_OF_MAPS, BPF_MAP_TYPE_ARRAY, false); printf("%s:PASS with inner ARRAY map\n", __func__); - _map_in_map_batch_ops(BPF_MAP_TYPE_HASH_OF_MAPS, BPF_MAP_TYPE_HASH); + _map_in_map_batch_ops(BPF_MAP_TYPE_HASH_OF_MAPS, BPF_MAP_TYPE_HASH, false); printf("%s:PASS with inner HASH map\n", __func__); }