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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EDE0C00140 for ; Fri, 12 Aug 2022 19:02:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237220AbiHLTCr (ORCPT ); Fri, 12 Aug 2022 15:02:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234033AbiHLTCq (ORCPT ); Fri, 12 Aug 2022 15:02:46 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5B142E7 for ; Fri, 12 Aug 2022 12:02:43 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-32e6a92567bso14268377b3.10 for ; Fri, 12 Aug 2022 12:02:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:from:to:cc; bh=XPk6FdjwBbwDgBh6u2eyiKeyBm8WmUk2D4CDTXFC/Hg=; b=Blx2XPNRZIFWzQtdxmhfEz7sMu3s8b/7TTxuTkMrGZPR333Sv5luoI9UBXalTAlywv JO8KYA0kuLJuoZ6ZXXKICDRqRXAuLkjeIpOeeDWwu/lCM9mEgsCQeOL1023M1G82Dlrx FjPmaJ4wRc/Plw2SIiqghxoQ61AHDsdqL/PBx7HodntpwZWNyESKHc8RYboRwLEolp7n ezbdosYn+Hu9vVmu/Myjy6Vwnx/UDMA1qr1ashqYFrFyGZzKbr0QEN6rWmbaCGdrR/hq HwLxYeW1HNq7eGPJ6ozhYmsrVWPPov2/M3sDfgWr5z72Zg1mKmtmPpRjI2e3vNKC9moL HYPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc; bh=XPk6FdjwBbwDgBh6u2eyiKeyBm8WmUk2D4CDTXFC/Hg=; b=6Jto3KXS76Wsy/KnrZ83XJAFikO8ENj+wuN9WoJZdadAieXIquF01MD3KADIr0bUFT amQzOM3aFXnDKs5zs7yumF/MYSWyydC4NHd41k7rI1fk+paqCmua6UCC7OWk7csVkKIj 5kmgO0nFvdou/pHWsYZj1iCTGekK71RjoLVkQjhcy6mWeu7XGoQkf/vl+0G4HLx4s8p+ NiFf5dKkc2z/tzCfb2G2Phee/e5FLxW831OEyNp/StGgPBD8WlfQxnc9K7KFAqWeHu9T s4U/h1cF6aoo4OO7eBZa3WSYGkr+FsqVMFsr04yD1BtrfkTxr7mLIRf3RIWMCNPTVh3Q wfHw== X-Gm-Message-State: ACgBeo1iP/eQVItrc+j4Q9ThDJvFqi/rnERbJcaXn/tFS/mPYloWyuYU +N9dswUxXbIzb0Pa0XqMdgoxt/2kYG23gDZbAnLUEEYPHUjLyxyGMBQWrizwd1bq7aPSmMzBMLp rBHTBRxRhwHVCPHPReJbiEocUdSirE7EzWaSpqEEm/Mp6Q4I4sw== X-Google-Smtp-Source: AA6agR6In1reqqirhKy5enLlZ9LFRsX4bLO8QI0Nmp8gSIO3knDIBjJm2Gz/euizwqUYGh0vT2Tz98E= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a81:50d4:0:b0:31f:5f85:566a with SMTP id e203-20020a8150d4000000b0031f5f85566amr5000445ywb.218.1660330962896; Fri, 12 Aug 2022 12:02:42 -0700 (PDT) Date: Fri, 12 Aug 2022 12:02:38 -0700 Message-Id: <20220812190241.3544528-1-sdf@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.595.g718a3a8f04-goog Subject: [PATCH bpf-next 0/3] bpf: expose bpf_{g,s}et_retval to more cgroup hooks From: Stanislav Fomichev To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Apparently, only a small subset of cgroup hooks actually falls back to cgroup_base_func_proto. This leads to unexpected result where not all cgroup helpers have bpf_{g,s}et_retval. It's getting harder and harder to manage which helpers are exported to which hooks. We now have the following call chains: - cg_skb_func_proto - sk_filter_func_proto - bpf_sk_base_func_proto - bpf_base_func_proto So by looking at cg_skb_func_proto it's pretty hard to understand what's going on. For cgroup helpers, I'm proposing we do the following instead: func_proto = cgroup_common_func_proto(); if (func_proto) return func_proto; /* optional, if hook has 'current' */ func_proto = cgroup_current_func_proto(); if (func_proto) return func_proto; ... switch (func_id) { /* hook specific helpers */ case BPF_FUNC_hook_specific_helper: return &xyz; default: /* always fall back to plain bpf_base_func_proto */ bpf_base_func_proto(func_id); } If this turns out more workable, we can follow up with converting the rest to the same pattern. Stanislav Fomichev (3): bpf: introduce cgroup_{common,current}_func_proto bpf: use cgroup_{common,current}_func_proto in more hooks selftests/bpf: make sure bpf_{g,s}et_retval is exposed everywhere include/linux/bpf.h | 16 +++ kernel/bpf/cgroup.c | 82 +++++++-------- kernel/bpf/helpers.c | 99 ++++++++++++++++++- net/core/filter.c | 78 ++++++--------- tools/testing/selftests/bpf/Makefile | 1 + .../bpf/cgroup_getset_retval_hooks.h | 25 +++++ .../bpf/prog_tests/cgroup_getset_retval.c | 48 +++++++++ .../bpf/progs/cgroup_getset_retval_hooks.c | 16 +++ 8 files changed, 270 insertions(+), 95 deletions(-) create mode 100644 tools/testing/selftests/bpf/cgroup_getset_retval_hooks.h create mode 100644 tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c -- 2.37.1.595.g718a3a8f04-goog