From patchwork Sun Jan 17 22:16:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alan Maguire X-Patchwork-Id: 12025855 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=-13.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 0DC6CC433E0 for ; Sun, 17 Jan 2021 22:21:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD8DB222B3 for ; Sun, 17 Jan 2021 22:21:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729455AbhAQWVa (ORCPT ); Sun, 17 Jan 2021 17:21:30 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:59238 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728172AbhAQWV3 (ORCPT ); Sun, 17 Jan 2021 17:21:29 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 10HMKTLX188305; Sun, 17 Jan 2021 22:20:29 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2020-01-29; bh=aQXP7VaR4helTx5fp3TxcstYosj8Dr8qshg/Npy+5HE=; b=dgT6IyMfYYDsofTr4x8Elmp4QLP2p/ghavxHC8fpP/3C3mzG3w5XGinkD+ZKyC1mvd1s Vr1IRRx40pV44i3h7mjIapEDDellBRW7n4nZR6qIoAdnbpm0zx2jvPcOFZ8e4NAh1EiY nuOXBW0Qs0lENhTyE5+42LUAq4RBSF/xHXEFEoSdYtJzVAHSVrRtgPHVcdN8NNT0MFgg P1Br9xPcc7bU4EtZpGpYwylsaAsqBt9aasMNLlu2Ard4t8ZTmtC3NkNk322hffYuBcdb 7KgbM+NCYqmpKe0krp8MmXTYMu5yfSjhMiptmJGXr8IEEgn6QGwNhb7UR9YL2x2inPj4 xA== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 363xyhj8ey-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 17 Jan 2021 22:20:29 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 10HMK2VJ160336; Sun, 17 Jan 2021 22:20:28 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 364a1vp91x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 17 Jan 2021 22:20:28 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 10HMKR1U028171; Sun, 17 Jan 2021 22:20:27 GMT Received: from localhost.localdomain (/95.45.14.174) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sun, 17 Jan 2021 14:20:27 -0800 From: Alan Maguire To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org Cc: kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, morbo@google.com, shuah@kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Alan Maguire Subject: [PATCH v2 bpf-next 0/4] libbpf: BTF dumper support for typed data Date: Sun, 17 Jan 2021 22:16:00 +0000 Message-Id: <1610921764-7526-1-git-send-email-alan.maguire@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9867 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 malwarescore=0 adultscore=0 mlxscore=0 spamscore=0 suspectscore=0 mlxlogscore=999 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101170140 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9867 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 phishscore=0 malwarescore=0 mlxlogscore=999 bulkscore=0 priorityscore=1501 spamscore=0 mlxscore=0 impostorscore=0 lowpriorityscore=0 suspectscore=0 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101170140 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a libbpf dumper function that supports dumping a representation of data passed in using the BTF id associated with the data in a manner similar to the bpf_snprintf_btf helper. Default output format is identical to that dumped by bpf_snprintf_btf(), for example a "struct sk_buff" representation would look like this: struct sk_buff){ (union){ (struct){ .next = (struct sk_buff *)0xffffffffffffffff, .prev = (struct sk_buff *)0xffffffffffffffff, (union){ .dev = (struct net_device *)0xffffffffffffffff, .dev_scratch = (long unsigned int)18446744073709551615, }, }, ... Patches 1 and 2 make functions available that are needed during dump operations. Patch 3 implements the dump functionality in a manner similar to that in kernel/bpf/btf.c, but with a view to fitting into libbpf more naturally. For example, rather than using flags, boolean dump options are used to control output. Patch 4 is a selftest that utilizes a dump printf function to snprintf the dump output to a string for comparison with expected output. Tests deliberately mirror those in snprintf_btf helper test to keep output consistent. Changes since RFC [1] - The initial approach explored was to share the kernel code with libbpf using #defines to paper over the different needs; however it makes more sense to try and fit in with libbpf code style for maintenance. A comment in the code points at the implementation in kernel/bpf/btf.c and notes that any issues found in it should be fixed there or vice versa; mirroring the tests should help with this also (Andrii) [1] https://lore.kernel.org/bpf/1610386373-24162-1-git-send-email-alan.maguire@oracle.com/T/#t Alan Maguire (4): libbpf: add btf_has_size() and btf_int() inlines libbpf: make skip_mods_and_typedefs available internally in libbpf libbpf: BTF dumper support for typed data selftests/bpf: add dump type data tests to btf dump tests tools/lib/bpf/btf.h | 36 + tools/lib/bpf/btf_dump.c | 974 ++++++++++++++++++++++ tools/lib/bpf/libbpf.c | 4 +- tools/lib/bpf/libbpf.map | 5 + tools/lib/bpf/libbpf_internal.h | 2 + tools/testing/selftests/bpf/prog_tests/btf_dump.c | 233 ++++++ 6 files changed, 1251 insertions(+), 3 deletions(-)