From patchwork Tue Mar 16 01:14:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin KaFai Lau X-Patchwork-Id: 12140917 X-Patchwork-Delegate: bpf@iogearbox.net 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 0BB63C433E9 for ; Tue, 16 Mar 2021 01:15:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5E9564F69 for ; Tue, 16 Mar 2021 01:15:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234183AbhCPBO6 (ORCPT ); Mon, 15 Mar 2021 21:14:58 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:49208 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234210AbhCPBOg (ORCPT ); Mon, 15 Mar 2021 21:14:36 -0400 Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 12G1E9wh027350 for ; Mon, 15 Mar 2021 18:14:36 -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-transfer-encoding : content-type; s=facebook; bh=F6CUvYk8IHbxWxopaZr46T24w8OFyqZTCCuT6Yk2rQc=; b=h6PhX61azdhARLt+jKxuxkuZTuRkZJIab7IEnal2W2cCHnSdfFB5mUfn6iNwAbyPceZX 0g/1OJEHUDvFlLvPa3M11Ea44/qYE8YxtgWoYTWd49hTlNycLaWrNNmeqf2nZJeKbeYe b9qi65LuVpgtMVg67vymVV7Yc8DFSsHWWuI= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 37a6brvneb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 15 Mar 2021 18:14:36 -0700 Received: from intmgw002.06.ash9.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::e) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Mon, 15 Mar 2021 18:14:35 -0700 Received: by devbig005.ftw2.facebook.com (Postfix, from userid 6611) id 9B8852942B57; Mon, 15 Mar 2021 18:14:32 -0700 (PDT) From: Martin KaFai Lau To: CC: Alexei Starovoitov , Daniel Borkmann , , Subject: [PATCH bpf-next 09/15] libbpf: Refactor codes for finding btf id of a kernel symbol Date: Mon, 15 Mar 2021 18:14:32 -0700 Message-ID: <20210316011432.4178797-1-kafai@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210316011336.4173585-1-kafai@fb.com> References: <20210316011336.4173585-1-kafai@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369,18.0.761 definitions=2021-03-15_15:2021-03-15,2021-03-15 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 malwarescore=0 adultscore=0 suspectscore=0 phishscore=0 mlxscore=0 mlxlogscore=999 priorityscore=1501 lowpriorityscore=0 bulkscore=0 clxscore=1015 spamscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2103160005 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch refactors code, that finds kernel btf_id by kind and symbol name, to a new function find_ksym_btf_id(). It also adds a new helper __btf_kind_str() to return a string by the numeric kind value. Signed-off-by: Martin KaFai Lau Acked-by: Andrii Nakryiko --- tools/lib/bpf/libbpf.c | 44 +++++++++++++++++++++++++++++++----------- 1 file changed, 33 insertions(+), 11 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 7d5f9b7877bc..8355b786b3db 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1929,9 +1929,9 @@ resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id) return btf_is_func_proto(t) ? t : NULL; } -static const char *btf_kind_str(const struct btf_type *t) +static const char *__btf_kind_str(__u16 kind) { - switch (btf_kind(t)) { + switch (kind) { case BTF_KIND_UNKN: return "void"; case BTF_KIND_INT: return "int"; case BTF_KIND_PTR: return "ptr"; @@ -1953,6 +1953,11 @@ static const char *btf_kind_str(const struct btf_type *t) } } +static const char *btf_kind_str(const struct btf_type *t) +{ + return __btf_kind_str(btf_kind(t)); +} + /* * Fetch integer attribute of BTF map definition. Such attributes are * represented using a pointer to an array, in which dimensionality of array @@ -7403,18 +7408,17 @@ static int bpf_object__read_kallsyms_file(struct bpf_object *obj) return err; } -static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, - struct extern_desc *ext) +static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name, + __u16 kind, struct btf **res_btf, + int *res_btf_fd) { - const struct btf_type *targ_var, *targ_type; - __u32 targ_type_id, local_type_id; - const char *targ_var_name; int i, id, btf_fd, err; struct btf *btf; btf = obj->btf_vmlinux; btf_fd = 0; - id = btf__find_by_name_kind(btf, ext->name, BTF_KIND_VAR); + id = btf__find_by_name_kind(btf, ksym_name, kind); + if (id == -ENOENT) { err = load_module_btfs(obj); if (err) @@ -7424,17 +7428,35 @@ static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, btf = obj->btf_modules[i].btf; /* we assume module BTF FD is always >0 */ btf_fd = obj->btf_modules[i].fd; - id = btf__find_by_name_kind(btf, ext->name, BTF_KIND_VAR); + id = btf__find_by_name_kind(btf, ksym_name, kind); if (id != -ENOENT) break; } } if (id <= 0) { - pr_warn("extern (var ksym) '%s': failed to find BTF ID in kernel BTF(s).\n", - ext->name); + pr_warn("extern (%s ksym) '%s': failed to find BTF ID in kernel BTF(s).\n", + __btf_kind_str(kind), ksym_name); return -ESRCH; } + *res_btf = btf; + *res_btf_fd = btf_fd; + return id; +} + +static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, + struct extern_desc *ext) +{ + const struct btf_type *targ_var, *targ_type; + __u32 targ_type_id, local_type_id; + const char *targ_var_name; + int id, btf_fd = 0, err; + struct btf *btf = NULL; + + id = find_ksym_btf_id(obj, ext->name, BTF_KIND_VAR, &btf, &btf_fd); + if (id < 0) + return id; + /* find local type_id */ local_type_id = ext->ksym.type_id;