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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 C75E9C32792 for ; Sat, 5 Oct 2019 05:03:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B19E222C8 for ; Sat, 5 Oct 2019 05:03:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570251810; bh=LReOpRKPdcrwiAk9e/OIw5Qmm8uarSusXKwmWyUlG80=; h=From:To:CC:Subject:Date:In-Reply-To:References:List-ID:From; b=JbjGrTRD1Z8L9UIlOChX36vtNhHniCIGBFgFAfz1bg0e2UwSw8eeIqOW1mPA0nbW/ DsiOGgS4HWl+Qcf6gwkiE+nNYFA4e9R6pA0CnwlTKmBni5J5f9BncmChkBMWnbh3Lg ZdGFPYFZFqG7wMD0Y1x+R7ze5Be3wwwF4UaBrsKo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726923AbfJEFD2 convert rfc822-to-8bit (ORCPT ); Sat, 5 Oct 2019 01:03:28 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:62526 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726774AbfJEFD1 (ORCPT ); Sat, 5 Oct 2019 01:03:27 -0400 Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id x954xMmk004907 for ; Fri, 4 Oct 2019 22:03:26 -0700 Received: from mail.thefacebook.com (mailout.thefacebook.com [199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2ved839s9n-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Fri, 04 Oct 2019 22:03:26 -0700 Received: from 2401:db00:2050:5076:face:0:7:0 (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::125) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1713.5; Fri, 4 Oct 2019 22:03:25 -0700 Received: by devbig007.ftw2.facebook.com (Postfix, from userid 572438) id 13D6176091D; Fri, 4 Oct 2019 22:03:23 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Alexei Starovoitov Smtp-Origin-Hostname: devbig007.ftw2.facebook.com To: CC: , , , , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next 04/10] libbpf: auto-detect btf_id of raw_tracepoint Date: Fri, 4 Oct 2019 22:03:08 -0700 Message-ID: <20191005050314.1114330-5-ast@kernel.org> X-Mailer: git-send-email 2.20.0 In-Reply-To: <20191005050314.1114330-1-ast@kernel.org> References: <20191005050314.1114330-1-ast@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,1.0.8 definitions=2019-10-05_02:2019-10-03,2019-10-05 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=988 mlxscore=0 impostorscore=0 clxscore=1034 spamscore=0 bulkscore=0 malwarescore=0 suspectscore=3 adultscore=0 phishscore=0 lowpriorityscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1908290000 definitions=main-1910050044 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org For raw tracepoint program types libbpf will try to find btf_id of raw tracepoint in vmlinux's BTF. It's a responsiblity of bpf program author to annotate the program with SEC("raw_tracepoint/name") where "name" is a valid raw tracepoint. If "name" is indeed a valid raw tracepoint then in-kernel BTF will have "btf_trace_##name" typedef that points to function prototype of that raw tracepoint. BTF description captures exact argument the kernel C code is passing into raw tracepoint. The kernel verifier will check the types while loading bpf program. Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/libbpf.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e0276520171b..0e6f7b41c521 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4591,6 +4591,22 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, continue; *prog_type = section_names[i].prog_type; *expected_attach_type = section_names[i].expected_attach_type; + if (*prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT) { + struct btf *btf = bpf_core_find_kernel_btf(); + char raw_tp_btf_name[128] = "btf_trace_"; + int ret; + + if (IS_ERR(btf)) + /* lack of kernel BTF is not a failure */ + return 0; + /* append "btf_trace_" prefix per kernel convention */ + strcpy(raw_tp_btf_name + sizeof("btf_trace_") - 1, + name + section_names[i].len); + ret = btf__find_by_name(btf, raw_tp_btf_name); + if (ret > 0) + *expected_attach_type = ret; + btf__free(btf); + } return 0; } pr_warning("failed to guess program type based on ELF section name '%s'\n", name); -- 2.20.0