tools lib bpf: Use IS_ERR() reporting macros with bpf_map__get_def()

And for consistency, rename it to bpf_map__def(), leaving "get" for
reference counting.

Also make it return a const pointer, as suggested by Wang.

Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-mer00xqkiho0ymg66b5i9luw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4dc617b..215be67 100644 (file)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1319,13 +1319,9 @@ int bpf_map__get_fd(struct bpf_map *map)
        return map->fd;
 }
 
-int bpf_map__get_def(struct bpf_map *map, struct bpf_map_def *pdef)
+const struct bpf_map_def *bpf_map__def(struct bpf_map *map)
 {
-       if (!map || !pdef)
-               return -EINVAL;
-
-       *pdef = map->def;
-       return 0;
+       return map ? &map->def : ERR_PTR(-EINVAL);
 }
 
 const char *bpf_map__name(struct bpf_map *map)

diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index f8fbba4..bad5bac 100644 (file)
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -181,7 +181,7 @@ bpf_map__next(struct bpf_map *map, struct bpf_object *obj);
             (pos) = bpf_map__next((pos), (obj)))
 
 int bpf_map__get_fd(struct bpf_map *map);
-int bpf_map__get_def(struct bpf_map *map, struct bpf_map_def *pdef);
+const struct bpf_map_def *bpf_map__def(struct bpf_map *map);
 const char *bpf_map__name(struct bpf_map *map);
 
 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);

diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index c819eb8..73c1e7c 100644 (file)
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -945,28 +945,26 @@ static int
 __bpf_map__config_value(struct bpf_map *map,
                        struct parse_events_term *term)
 {
-       struct bpf_map_def def;
        struct bpf_map_op *op;
        const char *map_name = bpf_map__name(map);
-       int err;
+       const struct bpf_map_def *def = bpf_map__def(map);
 
-       err = bpf_map__get_def(map, &def);
-       if (err) {
+       if (IS_ERR(def)) {
                pr_debug("Unable to get map definition from '%s'\n",
                         map_name);
                return -BPF_LOADER_ERRNO__INTERNAL;
        }
 
-       if (def.type != BPF_MAP_TYPE_ARRAY) {
+       if (def->type != BPF_MAP_TYPE_ARRAY) {
                pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
                         map_name);
                return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
        }
-       if (def.key_size < sizeof(unsigned int)) {
+       if (def->key_size < sizeof(unsigned int)) {
                pr_debug("Map %s has incorrect key size\n", map_name);
                return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
        }
-       switch (def.value_size) {
+       switch (def->value_size) {
        case 1:
        case 2:
        case 4:
@@ -1009,10 +1007,9 @@ __bpf_map__config_event(struct bpf_map *map,
                        struct perf_evlist *evlist)
 {
        struct perf_evsel *evsel;
-       struct bpf_map_def def;
+       const struct bpf_map_def *def;
        struct bpf_map_op *op;
        const char *map_name = bpf_map__name(map);
-       int err;
 
        evsel = perf_evlist__find_evsel_by_str(evlist, term->val.str);
        if (!evsel) {
@@ -1021,18 +1018,18 @@ __bpf_map__config_event(struct bpf_map *map,
                return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
        }
 
-       err = bpf_map__get_def(map, &def);
-       if (err) {
+       def = bpf_map__def(map);
+       if (IS_ERR(def)) {
                pr_debug("Unable to get map definition from '%s'\n",
                         map_name);
-               return err;
+               return PTR_ERR(def);
        }
 
        /*
         * No need to check key_size and value_size:
         * kernel has already checked them.
         */
-       if (def.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
+       if (def->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
                pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
                         map_name);
                return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
@@ -1081,9 +1078,8 @@ config_map_indices_range_check(struct parse_events_term *term,
                               const char *map_name)
 {
        struct parse_events_array *array = &term->array;
-       struct bpf_map_def def;
+       const struct bpf_map_def *def;
        unsigned int i;
-       int err;
 
        if (!array->nr_ranges)
                return 0;
@@ -1093,8 +1089,8 @@ config_map_indices_range_check(struct parse_events_term *term,
                return -BPF_LOADER_ERRNO__INTERNAL;
        }
 
-       err = bpf_map__get_def(map, &def);
-       if (err) {
+       def = bpf_map__def(map);
+       if (IS_ERR(def)) {
                pr_debug("ERROR: Unable to get map definition from '%s'\n",
                         map_name);
                return -BPF_LOADER_ERRNO__INTERNAL;
@@ -1105,7 +1101,7 @@ config_map_indices_range_check(struct parse_events_term *term,
                size_t length = array->ranges[i].length;
                unsigned int idx = start + length - 1;
 
-               if (idx >= def.max_entries) {
+               if (idx >= def->max_entries) {
                        pr_debug("ERROR: index %d too large\n", idx);
                        return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
                }
@@ -1198,14 +1194,14 @@ out:
 }
 
 typedef int (*map_config_func_t)(const char *name, int map_fd,
-                                struct bpf_map_def *pdef,
+                                const struct bpf_map_def *pdef,
                                 struct bpf_map_op *op,
                                 void *pkey, void *arg);
 
 static int
 foreach_key_array_all(map_config_func_t func,
                      void *arg, const char *name,
-                     int map_fd, struct bpf_map_def *pdef,
+                     int map_fd, const struct bpf_map_def *pdef,
                      struct bpf_map_op *op)
 {
        unsigned int i;
@@ -1225,7 +1221,7 @@ foreach_key_array_all(map_config_func_t func,
 static int
 foreach_key_array_ranges(map_config_func_t func, void *arg,
                         const char *name, int map_fd,
-                        struct bpf_map_def *pdef,
+                        const struct bpf_map_def *pdef,
                         struct bpf_map_op *op)
 {
        unsigned int i, j;
@@ -1256,7 +1252,7 @@ bpf_map_config_foreach_key(struct bpf_map *map,
 {
        int err, map_fd;
        struct bpf_map_op *op;
-       struct bpf_map_def def;
+       const struct bpf_map_def *def;
        const char *name = bpf_map__name(map);
        struct bpf_map_priv *priv = bpf_map__priv(map);
 
@@ -1269,8 +1265,8 @@ bpf_map_config_foreach_key(struct bpf_map *map,
                return 0;
        }
 
-       err = bpf_map__get_def(map, &def);
-       if (err) {
+       def = bpf_map__def(map);
+       if (IS_ERR(def)) {
                pr_debug("ERROR: failed to get definition from map %s\n", name);
                return -BPF_LOADER_ERRNO__INTERNAL;
        }
@@ -1281,17 +1277,17 @@ bpf_map_config_foreach_key(struct bpf_map *map,
        }
 
        list_for_each_entry(op, &priv->ops_list, list) {
-               switch (def.type) {
+               switch (def->type) {
                case BPF_MAP_TYPE_ARRAY:
                case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
                        switch (op->key_type) {
                        case BPF_MAP_KEY_ALL:
                                err = foreach_key_array_all(func, arg, name,
-                                                           map_fd, &def, op);
+                                                           map_fd, def, op);
                                break;
                        case BPF_MAP_KEY_RANGES:
                                err = foreach_key_array_ranges(func, arg, name,
-                                                              map_fd, &def,
+                                                              map_fd, def,
                                                               op);
                                break;
                        default:
@@ -1401,7 +1397,7 @@ apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
 
 static int
 apply_obj_config_map_for_key(const char *name, int map_fd,
-                            struct bpf_map_def *pdef __maybe_unused,
+                            const struct bpf_map_def *pdef,
                             struct bpf_map_op *op,
                             void *pkey, void *arg __maybe_unused)
 {