From patchwork Thu Aug 11 23:04:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joanne Koong X-Patchwork-Id: 12941787 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3F36C25B0E for ; Thu, 11 Aug 2022 23:05:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236457AbiHKXFl (ORCPT ); Thu, 11 Aug 2022 19:05:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236577AbiHKXFf (ORCPT ); Thu, 11 Aug 2022 19:05:35 -0400 Received: from 69-171-232-181.mail-mxout.facebook.com (69-171-232-181.mail-mxout.facebook.com [69.171.232.181]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A08681114A for ; Thu, 11 Aug 2022 16:05:34 -0700 (PDT) Received: by devbig010.atn6.facebook.com (Postfix, from userid 115148) id 9A4AB104B4E8B; Thu, 11 Aug 2022 16:05:21 -0700 (PDT) From: Joanne Koong To: bpf@vger.kernel.org Cc: kafai@fb.com, kuba@kernel.org, andrii@kernel.org, daniel@iogearbox.net, ast@kernel.org, netdev@vger.kernel.org, kernel-team@fb.com, Joanne Koong Subject: [PATCH bpf-next v2 0/3] Add skb + xdp dynptrs Date: Thu, 11 Aug 2022 16:04:58 -0700 Message-Id: <20220811230501.2632393-1-joannelkoong@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patchset is the 2nd in the dynptr series. The 1st can be found here [0]. This patchset adds skb and xdp type dynptrs, which have two main benefits for packet parsing: * allowing operations on sizes that are not statically known at compile-time (eg variable-sized accesses). * more ergonomic and less brittle iteration through data (eg does not need manual if checking for being within bounds of data_end) When comparing the differences in runtime for packet parsing without dynptrs vs. with dynptrs for the more simple cases, there is no noticeable difference. For the more complex cases where lengths are non-statically known at compile time, there can be a significant speed-up when using dynptrs (eg a 2x speed up for cls redirection). Patch 3 contains more details as well as examples of how to use skb and xdp dynptrs. [0] https://lore.kernel.org/bpf/20220523210712.3641569-1-joannelkoong@gmail.com/ --- Changelog: v1 = https://lore.kernel.org/bpf/20220726184706.954822-1-joannelkoong@gmail.com/ v1 -> v2 * Return data slices to rd-only skb dynptrs (Martin) * bpf_dynptr_write allows writes to frags for skb dynptrs, but always invalidates associated data slices (Martin) * Use switch casing instead of ifs (Andrii) * Use 0xFD for experimental kind number in the selftest (Zvi) * Put selftest conversions w/ dynptrs into new files (Alexei) * Add new selftest "test_cls_redirect_dynptr.c" Joanne Koong (3): bpf: Add skb dynptrs bpf: Add xdp dynptrs selftests/bpf: tests for using dynptrs to parse skb and xdp buffers include/linux/bpf.h | 14 +- include/linux/filter.h | 7 + include/uapi/linux/bpf.h | 59 +- kernel/bpf/helpers.c | 93 +- kernel/bpf/verifier.c | 105 +- net/core/filter.c | 99 +- tools/include/uapi/linux/bpf.h | 59 +- .../selftests/bpf/prog_tests/cls_redirect.c | 25 + .../testing/selftests/bpf/prog_tests/dynptr.c | 132 ++- .../selftests/bpf/prog_tests/l4lb_all.c | 2 + .../bpf/prog_tests/parse_tcp_hdr_opt.c | 85 ++ .../selftests/bpf/prog_tests/xdp_attach.c | 9 +- .../testing/selftests/bpf/progs/dynptr_fail.c | 111 ++ .../selftests/bpf/progs/dynptr_success.c | 29 + .../bpf/progs/test_cls_redirect_dynptr.c | 968 ++++++++++++++++++ .../bpf/progs/test_l4lb_noinline_dynptr.c | 468 +++++++++ .../bpf/progs/test_parse_tcp_hdr_opt.c | 119 +++ .../bpf/progs/test_parse_tcp_hdr_opt_dynptr.c | 110 ++ .../selftests/bpf/progs/test_xdp_dynptr.c | 240 +++++ .../selftests/bpf/test_tcp_hdr_options.h | 1 + 20 files changed, 2649 insertions(+), 86 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/parse_tcp_hdr_opt.c create mode 100644 tools/testing/selftests/bpf/progs/test_cls_redirect_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_l4lb_noinline_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_parse_tcp_hdr_opt.c create mode 100644 tools/testing/selftests/bpf/progs/test_parse_tcp_hdr_opt_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_dynptr.c