1 files changed, 30 insertions, 26 deletions

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ad43b6ce825e6..81bf01d67671b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1374,22 +1374,20 @@ static bool bpf_map_type__is_map_in_map(enum bpf_map_type type)
 
 static int find_elf_sec_sz(const struct bpf_object *obj, const char *name, __u32 *size)
 {
-	int ret = -ENOENT;
 	Elf_Data *data;
 	Elf_Scn *scn;
 
-	*size = 0;
 	if (!name)
 		return -EINVAL;
 
 	scn = elf_sec_by_name(obj, name);
 	data = elf_sec_data(obj, scn);
 	if (data) {
-		ret = 0; /* found it */
 		*size = data->d_size;
+		return 0; /* found it */
 	}
 
-	return *size ? 0 : ret;
+	return -ENOENT;
 }
 
 static int find_elf_var_offset(const struct bpf_object *obj, const char *name, __u32 *off)
@@ -2795,7 +2793,7 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
 		goto sort_vars;
 
 	ret = find_elf_sec_sz(obj, name, &size);
-	if (ret || !size || (t->size && t->size != size)) {
+	if (ret || !size) {
 		pr_debug("Invalid size for section %s: %u bytes\n", name, size);
 		return -ENOENT;
 	}
@@ -4861,7 +4859,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 	LIBBPF_OPTS(bpf_map_create_opts, create_attr);
 	struct bpf_map_def *def = &map->def;
 	const char *map_name = NULL;
-	__u32 max_entries;
 	int err = 0;
 
 	if (kernel_supports(obj, FEAT_PROG_NAME))
@@ -4871,21 +4868,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 	create_attr.numa_node = map->numa_node;
 	create_attr.map_extra = map->map_extra;
 
-	if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !def->max_entries) {
-		int nr_cpus;
-
-		nr_cpus = libbpf_num_possible_cpus();
-		if (nr_cpus < 0) {
-			pr_warn("map '%s': failed to determine number of system CPUs: %d\n",
-				map->name, nr_cpus);
-			return nr_cpus;
-		}
-		pr_debug("map '%s': setting size to %d\n", map->name, nr_cpus);
-		max_entries = nr_cpus;
-	} else {
-		max_entries = def->max_entries;
-	}
-
 	if (bpf_map__is_struct_ops(map))
 		create_attr.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
 
@@ -4935,7 +4917,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 
 	if (obj->gen_loader) {
 		bpf_gen__map_create(obj->gen_loader, def->type, map_name,
-				    def->key_size, def->value_size, max_entries,
+				    def->key_size, def->value_size, def->max_entries,
 				    &create_attr, is_inner ? -1 : map - obj->maps);
 		/* Pretend to have valid FD to pass various fd >= 0 checks.
 		 * This fd == 0 will not be used with any syscall and will be reset to -1 eventually.
@@ -4944,7 +4926,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 	} else {
 		map->fd = bpf_map_create(def->type, map_name,
 					 def->key_size, def->value_size,
-					 max_entries, &create_attr);
+					 def->max_entries, &create_attr);
 	}
 	if (map->fd < 0 && (create_attr.btf_key_type_id ||
 			    create_attr.btf_value_type_id)) {
@@ -4961,7 +4943,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 		map->btf_value_type_id = 0;
 		map->fd = bpf_map_create(def->type, map_name,
 					 def->key_size, def->value_size,
-					 max_entries, &create_attr);
+					 def->max_entries, &create_attr);
 	}
 
 	err = map->fd < 0 ? -errno : 0;
@@ -5065,6 +5047,24 @@ static int bpf_object_init_prog_arrays(struct bpf_object *obj)
 	return 0;
 }
 
+static int map_set_def_max_entries(struct bpf_map *map)
+{
+	if (map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !map->def.max_entries) {
+		int nr_cpus;
+
+		nr_cpus = libbpf_num_possible_cpus();
+		if (nr_cpus < 0) {
+			pr_warn("map '%s': failed to determine number of system CPUs: %d\n",
+				map->name, nr_cpus);
+			return nr_cpus;
+		}
+		pr_debug("map '%s': setting size to %d\n", map->name, nr_cpus);
+		map->def.max_entries = nr_cpus;
+	}
+
+	return 0;
+}
+
 static int
 bpf_object__create_maps(struct bpf_object *obj)
 {
@@ -5097,6 +5097,10 @@ bpf_object__create_maps(struct bpf_object *obj)
 			continue;
 		}
 
+		err = map_set_def_max_entries(map);
+		if (err)
+			goto err_out;
+
 		retried = false;
 retry:
 		if (map->pin_path) {
@@ -10947,7 +10951,7 @@ struct perf_buffer *perf_buffer__new_raw_v0_6_0(int map_fd, size_t page_cnt,
 {
 	struct perf_buffer_params p = {};
 
-	if (page_cnt == 0 || !attr)
+	if (!attr)
 		return libbpf_err_ptr(-EINVAL);
 
 	if (!OPTS_VALID(opts, perf_buffer_raw_opts))
@@ -10988,7 +10992,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt,
 	__u32 map_info_len;
 	int err, i, j, n;
 
-	if (page_cnt & (page_cnt - 1)) {
+	if (page_cnt == 0 || (page_cnt & (page_cnt - 1))) {
 		pr_warn("page count should be power of two, but is %zu\n",
 			page_cnt);
 		return ERR_PTR(-EINVAL);