On Sun, Sep 5, 2021 at 3:09 AM Hengqi Chen <hengqi.chen@xxxxxxxxx> wrote: > > A bunch of BPF maps do not support specifying types for key and value. s/types/BTF types/, it's a bit confusing otherwise > This is non-uniform and inconvenient[0]. Currently, libbpf uses a retry > logic which removes BTF type IDs when BPF map creation failed. Instead > of retrying, this commit recognizes those specialized map and removes s/map/maps/ > BTF type IDs when creating BPF map. > > [0] Closes: https://github.com/libbpf/libbpf/issues/355 > > Signed-off-by: Hengqi Chen <hengqi.chen@xxxxxxxxx> > --- For patch sets consisting of two or more patches, we ask for a cover letter, so for the next revision please provide a cover letter with an overall description of what the series is about. > tools/lib/bpf/libbpf.c | 35 ++++++++++++++++++++--------------- > 1 file changed, 20 insertions(+), 15 deletions(-) > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index 88d8825fc6f6..7068c4d07337 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -4613,6 +4613,26 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b > create_attr.inner_map_fd = map->inner_map_fd; > } > > + if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || > + def->type == BPF_MAP_TYPE_STACK_TRACE || > + def->type == BPF_MAP_TYPE_CGROUP_ARRAY || > + def->type == BPF_MAP_TYPE_ARRAY_OF_MAPS || > + def->type == BPF_MAP_TYPE_HASH_OF_MAPS || > + def->type == BPF_MAP_TYPE_DEVMAP || > + def->type == BPF_MAP_TYPE_SOCKMAP || > + def->type == BPF_MAP_TYPE_CPUMAP || > + def->type == BPF_MAP_TYPE_XSKMAP || > + def->type == BPF_MAP_TYPE_SOCKHASH || > + def->type == BPF_MAP_TYPE_QUEUE || > + def->type == BPF_MAP_TYPE_STACK || > + def->type == BPF_MAP_TYPE_DEVMAP_HASH) { > + create_attr.btf_fd = 0; > + create_attr.btf_key_type_id = 0; > + create_attr.btf_value_type_id = 0; > + map->btf_key_type_id = 0; > + map->btf_value_type_id = 0; > + } Let's do this as a more succinct switch statement. Consider also slightly rearranging entries to keep "related" map types together: - SOCKMAP + SOCKHASH - DEVMAP + DEVMAP_HASH + CPUMAP + XSKMAP Thanks! > + > if (obj->gen_loader) { > bpf_gen__map_create(obj->gen_loader, &create_attr, is_inner ? -1 : map - obj->maps); > /* Pretend to have valid FD to pass various fd >= 0 checks. > @@ -4622,21 +4642,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b > } else { > map->fd = bpf_create_map_xattr(&create_attr); > } > - if (map->fd < 0 && (create_attr.btf_key_type_id || > - create_attr.btf_value_type_id)) { > - char *cp, errmsg[STRERR_BUFSIZE]; > - > - err = -errno; > - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); > - pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", > - map->name, cp, err); > - create_attr.btf_fd = 0; > - create_attr.btf_key_type_id = 0; > - create_attr.btf_value_type_id = 0; > - map->btf_key_type_id = 0; > - map->btf_value_type_id = 0; > - map->fd = bpf_create_map_xattr(&create_attr); > - } > Please don't remove this fallback logic. There are multiple situations where libbpf might need to retry map creation without BTF. > err = map->fd < 0 ? -errno : 0; > > -- > 2.25.1 >
