From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D71E3C4321A for ; Fri, 28 Jun 2019 15:25:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A63FE2064A for ; Fri, 28 Jun 2019 15:25:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="bj+Z6eMj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726902AbfF1PZq (ORCPT ); Fri, 28 Jun 2019 11:25:46 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:27096 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726762AbfF1PZq (ORCPT ); Fri, 28 Jun 2019 11:25:46 -0400 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5SFOI92025802 for ; Fri, 28 Jun 2019 08:25:44 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=X76oJ7beTx+bSEj2jks83TttnQqsCfjae1BFZG7LRnw=; b=bj+Z6eMj1Bv8byq8shCez1yVk2JyhK6PcvpjV7on0bqSLXoC2JFN6wqvm6tUpXaWDhYJ SAe/NBEKG7AHkXxe3KkpHy0AtB3CltnK6gidS/6HACuMr4RO7N5vYMC1x8rRgtwqUO4x 1UW0dvW2MGJiZRENnskOl1XNuHB1xOYzNbw= Received: from mail.thefacebook.com (mailout.thefacebook.com [199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2td9ka279f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Fri, 28 Jun 2019 08:25:44 -0700 Received: from mx-out.facebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::130) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1713.5; Fri, 28 Jun 2019 08:25:43 -0700 Received: by dev101.prn2.facebook.com (Postfix, from userid 137359) id 05797861486; Fri, 28 Jun 2019 08:25:43 -0700 (PDT) Smtp-Origin-Hostprefix: dev From: Andrii Nakryiko Smtp-Origin-Hostname: dev101.prn2.facebook.com To: , , , , , CC: Andrii Nakryiko Smtp-Origin-Cluster: prn2c23 Subject: [PATCH v2 bpf-next 1/4] libbpf: capture value in BTF type info for BTF-defined map defs Date: Fri, 28 Jun 2019 08:25:36 -0700 Message-ID: <20190628152539.3014719-2-andriin@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190628152539.3014719-1-andriin@fb.com> References: <20190628152539.3014719-1-andriin@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-06-28_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=926 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906280178 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Change BTF-defined map definitions to capture compile-time integer values as part of BTF type definition, to avoid split of key/value type information and actual type/size/flags initialization for maps. Signed-off-by: Andrii Nakryiko --- tools/lib/bpf/libbpf.c | 58 ++++++++++++++++++++---------------------- 1 file changed, 28 insertions(+), 30 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 6e6ebef11ba3..9e099ecb2c2b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1028,40 +1028,40 @@ static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, } } -static bool get_map_field_int(const char *map_name, - const struct btf *btf, +/* + * Fetch integer attribute of BTF map definition. Such attributes are + * represented using a pointer to an array, in which dimensionality of array + * encodes specified integer value. E.g., int (*type)[BPF_MAP_TYPE_ARRAY]; + * encodes `type => BPF_MAP_TYPE_ARRAY` key/value pair completely using BTF + * type definition, while using only sizeof(void *) space in ELF data section. + */ +static bool get_map_field_int(const char *map_name, const struct btf *btf, const struct btf_type *def, - const struct btf_member *m, - const void *data, __u32 *res) { + const struct btf_member *m, __u32 *res) { const struct btf_type *t = skip_mods_and_typedefs(btf, m->type); const char *name = btf__name_by_offset(btf, m->name_off); - __u32 int_info = *(const __u32 *)(const void *)(t + 1); + const struct btf_array *arr_info; + const struct btf_type *arr_t; - if (BTF_INFO_KIND(t->info) != BTF_KIND_INT) { - pr_warning("map '%s': attr '%s': expected INT, got %u.\n", + if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { + pr_warning("map '%s': attr '%s': expected PTR, got %u.\n", map_name, name, BTF_INFO_KIND(t->info)); return false; } - if (t->size != 4 || BTF_INT_BITS(int_info) != 32 || - BTF_INT_OFFSET(int_info)) { - pr_warning("map '%s': attr '%s': expected 32-bit non-bitfield integer, " - "got %u-byte (%d-bit) one with bit offset %d.\n", - map_name, name, t->size, BTF_INT_BITS(int_info), - BTF_INT_OFFSET(int_info)); - return false; - } - if (BTF_INFO_KFLAG(def->info) && BTF_MEMBER_BITFIELD_SIZE(m->offset)) { - pr_warning("map '%s': attr '%s': bitfield is not supported.\n", - map_name, name); + + arr_t = btf__type_by_id(btf, t->type); + if (!arr_t) { + pr_warning("map '%s': attr '%s': type [%u] not found.\n", + map_name, name, t->type); return false; } - if (m->offset % 32) { - pr_warning("map '%s': attr '%s': unaligned fields are not supported.\n", - map_name, name); + if (BTF_INFO_KIND(arr_t->info) != BTF_KIND_ARRAY) { + pr_warning("map '%s': attr '%s': expected ARRAY, got %u.\n", + map_name, name, BTF_INFO_KIND(arr_t->info)); return false; } - - *res = *(const __u32 *)(data + m->offset / 8); + arr_info = (const void *)(arr_t + 1); + *res = arr_info->nelems; return true; } @@ -1074,7 +1074,6 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, const struct btf_var_secinfo *vi; const struct btf_var *var_extra; const struct btf_member *m; - const void *def_data; const char *map_name; struct bpf_map *map; int vlen, i; @@ -1131,7 +1130,6 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, pr_debug("map '%s': at sec_idx %d, offset %zu.\n", map_name, map->sec_idx, map->sec_offset); - def_data = data->d_buf + vi->offset; vlen = BTF_INFO_VLEN(def->info); m = (const void *)(def + 1); for (i = 0; i < vlen; i++, m++) { @@ -1144,19 +1142,19 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, } if (strcmp(name, "type") == 0) { if (!get_map_field_int(map_name, obj->btf, def, m, - def_data, &map->def.type)) + &map->def.type)) return -EINVAL; pr_debug("map '%s': found type = %u.\n", map_name, map->def.type); } else if (strcmp(name, "max_entries") == 0) { if (!get_map_field_int(map_name, obj->btf, def, m, - def_data, &map->def.max_entries)) + &map->def.max_entries)) return -EINVAL; pr_debug("map '%s': found max_entries = %u.\n", map_name, map->def.max_entries); } else if (strcmp(name, "map_flags") == 0) { if (!get_map_field_int(map_name, obj->btf, def, m, - def_data, &map->def.map_flags)) + &map->def.map_flags)) return -EINVAL; pr_debug("map '%s': found map_flags = %u.\n", map_name, map->def.map_flags); @@ -1164,7 +1162,7 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, __u32 sz; if (!get_map_field_int(map_name, obj->btf, def, m, - def_data, &sz)) + &sz)) return -EINVAL; pr_debug("map '%s': found key_size = %u.\n", map_name, sz); @@ -1207,7 +1205,7 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, __u32 sz; if (!get_map_field_int(map_name, obj->btf, def, m, - def_data, &sz)) + &sz)) return -EINVAL; pr_debug("map '%s': found value_size = %u.\n", map_name, sz); -- 2.17.1