From patchwork Thu Nov 5 04:51:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1394714 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CRWMw3RqTz9sSs for ; Thu, 5 Nov 2020 15:52:12 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731604AbgKEEwL convert rfc822-to-8bit (ORCPT ); Wed, 4 Nov 2020 23:52:11 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:21786 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730336AbgKEEwL (ORCPT ); Wed, 4 Nov 2020 23:52:11 -0500 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0A54o4KH030443 for ; Wed, 4 Nov 2020 20:52:10 -0800 Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 34kf5c7t0y-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 04 Nov 2020 20:52:10 -0800 Received: from intmgw004.03.ash8.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Wed, 4 Nov 2020 20:52:08 -0800 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id C808C2EC8E08; Wed, 4 Nov 2020 20:51:57 -0800 (PST) From: Andrii Nakryiko To: , , , CC: , , Arnaldo Carvalho de Melo Subject: [RFC PATCH bpf-next 5/5] tools/bpftool: add support for in-kernel and named BTF in `btf show` Date: Wed, 4 Nov 2020 20:51:40 -0800 Message-ID: <20201105045140.2589346-6-andrii@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20201105045140.2589346-1-andrii@kernel.org> References: <20201105045140.2589346-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-11-05_01:2020-11-05,2020-11-05 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 adultscore=0 spamscore=0 clxscore=1015 phishscore=0 impostorscore=0 mlxscore=0 mlxlogscore=999 suspectscore=9 priorityscore=1501 malwarescore=0 bulkscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011050035 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Display vmlinux BTF name and kernel module names when listing available BTFs on the system. In human-readable output mode, module BTFs are reported with "name [module-name]", while vmlinux BTF is reported as "name [vmlinux]". vmlinux BTF, as returned from the kernel, has an empty name. Square brackets are added by bpftool and follow kernel convention when displaying modules in human-readable text outputs. [vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s 1: name [vmlinux] size 4082281B 6: size 2365B prog_ids 8,6 map_ids 3 7: name [button] size 46895B 8: name [pcspkr] size 42328B 9: name [serio_raw] size 39375B 10: name [floppy] size 57185B 11: name [i2c_core] size 76186B 12: name [crc32c_intel] size 16036B 13: name [i2c_piix4] size 50497B 14: name [irqbypass] size 14124B 15: name [kvm] size 197985B 16: name [kvm_intel] size 123564B 17: name [cryptd] size 42466B 18: name [crypto_simd] size 17187B 19: name [glue_helper] size 39205B 20: name [aesni_intel] size 41034B 25: size 36150B pids bpftool(2519) In JSON mode, two fields (boolean "kernel" and string "name") are reported for each BTF object. vmlinux BTF is reported with name "vmlinux" (kernel itself returns and empty name for vmlinux BTF). [vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s -jp [{ "id": 1, "size": 4082281, "prog_ids": [], "map_ids": [], "kernel": true, "name": "vmlinux" },{ "id": 6, "size": 2365, "prog_ids": [8,6 ], "map_ids": [3 ], "kernel": false },{ "id": 7, "size": 46895, "prog_ids": [], "map_ids": [], "kernel": true, "name": "button" },{ ... Signed-off-by: Andrii Nakryiko --- tools/bpf/bpftool/btf.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index c96b56e8e3a4..9a7ff9b4ba5f 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -742,9 +742,14 @@ show_btf_plain(struct bpf_btf_info *info, int fd, struct btf_attach_table *btf_map_table) { struct btf_attach_point *obj; + const char *name = u64_to_ptr(info->name); int n; printf("%u: ", info->id); + if (info->kernel_btf) + printf("name [%s] ", name && name[0] ? name : "vmlinux"); + else if (name && name[0]) + printf("name %s ", name); printf("size %uB", info->btf_size); n = 0; @@ -771,6 +776,7 @@ show_btf_json(struct bpf_btf_info *info, int fd, struct btf_attach_table *btf_map_table) { struct btf_attach_point *obj; + const char *name = u64_to_ptr(info->name); jsonw_start_object(json_wtr); /* btf object */ jsonw_uint_field(json_wtr, "id", info->id); @@ -796,6 +802,13 @@ show_btf_json(struct bpf_btf_info *info, int fd, emit_obj_refs_json(&refs_table, info->id, json_wtr); /* pids */ + jsonw_bool_field(json_wtr, "kernel", info->kernel_btf); + + if (name && name[0]) + jsonw_string_field(json_wtr, "name", name); + else if (info->kernel_btf) + jsonw_string_field(json_wtr, "name", "vmlinux"); + jsonw_end_object(json_wtr); /* btf object */ } @@ -803,15 +816,30 @@ static int show_btf(int fd, struct btf_attach_table *btf_prog_table, struct btf_attach_table *btf_map_table) { - struct bpf_btf_info info = {}; + struct bpf_btf_info info; __u32 len = sizeof(info); + char name[64]; int err; + memset(&info, 0, sizeof(info)); err = bpf_obj_get_info_by_fd(fd, &info, &len); if (err) { p_err("can't get BTF object info: %s", strerror(errno)); return -1; } + /* if kernel support emitting BTF object name, pass name pointer */ + if (info.name_len) { + memset(&info, 0, sizeof(info)); + info.name_len = sizeof(name); + info.name = ptr_to_u64(name); + len = sizeof(info); + + err = bpf_obj_get_info_by_fd(fd, &info, &len); + if (err) { + p_err("can't get BTF object info: %s", strerror(errno)); + return -1; + } + } if (json_output) show_btf_json(&info, fd, btf_prog_table, btf_map_table);