From patchwork Tue May 4 11:05:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alejandro Colomar X-Patchwork-Id: 12237981 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 DAA22C433ED for ; Tue, 4 May 2021 11:05:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2C54613BC for ; Tue, 4 May 2021 11:05:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229959AbhEDLGm (ORCPT ); Tue, 4 May 2021 07:06:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229903AbhEDLGl (ORCPT ); Tue, 4 May 2021 07:06:41 -0400 Received: from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com [IPv6:2a00:1450:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF01BC061574; Tue, 4 May 2021 04:05:45 -0700 (PDT) Received: by mail-wr1-x42c.google.com with SMTP id x5so8889332wrv.13; Tue, 04 May 2021 04:05:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jBexOv/slXZrUqoBk/6dME5LyTQkC5h8UHzK8vFSGV0=; b=bGw0TUolt0fr1Mj/tO4Z5l3OL2UgcNPGr5SjtE9TQZdOFF6P1HHwvvcuDxmHzR7TWH 25W1zF8pIkB+Tkn8NFWnS2mumdQfeYiE83ef8+GV09LsjFxmkE2Ypc8k4c+PhM6xSDea ffdmjvsvJeyiPxeZb9Zg9sGhG/JnI2i+vsv8mFYq5UiDBfSSBqccXMb7ItNFnzrb3BOB CES3h4j4wznLfngqRZpc0k5hOcRV0bOLLgaqhE347rqF/49d06QkPgD559LR1boDmBSz V5Z5KTrUAtDbV99yQXkpEBJyT7Gjc/EwVTm3iwwIKtDJtAocjgFSXqsEfZwT11+TDXgq bBbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jBexOv/slXZrUqoBk/6dME5LyTQkC5h8UHzK8vFSGV0=; b=TAbQojzZrSrbHGTKYjv/6YgN9gW60wHp38iERkT3YBuJ04AfTkBwO/HfZ9piQMaVs7 cnn697ZiiF6HMhZHSVGbd9dN15UOncjpyLrJQj+9QYisM0n8+hXWsDKbAFEsuWd8sq3V G/8p+elDyDkmrbvgLYEJ44yb3iTDahXgG1yrl+HVMRzrFqy3djWJDhlLxQqxBlYMLjhY c7MVaNaBv1SWBAXRR+QTzk7PNRTpWRjl/WHEG2Qc6fR945QHfAyk0wo6cHU49JJBpKnK ZlaiXsgjbXlBP3UIX3g6vx+uzs+oSb6v3tN97PqukYVIhIjOUadCzuJmLy5eCalQ967b mAEQ== X-Gm-Message-State: AOAM530rrNWNMn+vOxL1aG1g8ceG0xFsrKJ2UvB4en6mvaCJGmP00ngR ah5M1/WzP6r5UUyJA1sXBfM= X-Google-Smtp-Source: ABdhPJw47QkoJpJSP1YPM0MC+fPhs/05hHrWzAdxeUw5qEExJJXq+uqU1z5Qjad2cZ6BA+EyTVcMTw== X-Received: by 2002:adf:e811:: with SMTP id o17mr14669020wrm.71.1620126344302; Tue, 04 May 2021 04:05:44 -0700 (PDT) Received: from sqli.sqli.com ([195.53.121.100]) by smtp.googlemail.com with ESMTPSA id o17sm16769939wrs.48.2021.05.04.04.05.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 May 2021 04:05:43 -0700 (PDT) From: Alejandro Colomar To: mtk.manpages@gmail.com, linux-man@vger.kernel.org Cc: Alejandro Colomar , LKML , glibc , GCC , Alexei Starovoitov , bpf , David Laight , Zack Weinberg , Joseph Myers Subject: [RFC v2] bpf.2: Use standard types and attributes Date: Tue, 4 May 2021 13:05:20 +0200 Message-Id: <20210504110519.16097-1-alx.manpages@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210423230609.13519-1-alx.manpages@gmail.com> References: <20210423230609.13519-1-alx.manpages@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-State: RFC Some manual pages are already using C99 syntax for integral types 'uint32_t', but some aren't. There are some using kernel syntax '__u32'. Fix those. Some pages also document attributes, using GNU syntax '__attribute__((xxx))'. Update those to use the shorter and more portable C11 keywords such as 'alignas()' when possible, and C2x syntax '[[gnu::xxx]]' elsewhere, which hasn't been standardized yet, but is already implemented in GCC, and available through either --std=c2x or any of the --std=gnu... options. The standard isn't very clear on how to use alignas() or [[]]-style attributes, so the following link is useful in the case of 'alignas()' and '[[gnu::aligned()]]': Signed-off-by: Alejandro Colomar Cc: LKML Cc: glibc Cc: GCC Cc: Alexei Starovoitov Cc: bpf Cc: David Laight Cc: Zack Weinberg Cc: Joseph Myers Nacked-by: Alexei Starovoitov Nacked-by: Greg Kroah-Hartman --- man2/bpf.2 | 49 ++++++++++++++++++++++++------------------------- 1 file changed, 24 insertions(+), 25 deletions(-) diff --git a/man2/bpf.2 b/man2/bpf.2 index 6e1ffa198..04b8fbcef 100644 --- a/man2/bpf.2 +++ b/man2/bpf.2 @@ -186,41 +186,40 @@ commands: .PP .in +4n .EX -union bpf_attr { +union [[gnu::aligned(8)]] bpf_attr { struct { /* Used by BPF_MAP_CREATE */ - __u32 map_type; - __u32 key_size; /* size of key in bytes */ - __u32 value_size; /* size of value in bytes */ - __u32 max_entries; /* maximum number of entries - in a map */ + uint32_t map_type; + uint32_t key_size; /* size of key in bytes */ + uint32_t value_size; /* size of value in bytes */ + uint32_t max_entries; /* maximum number of entries + in a map */ }; - struct { /* Used by BPF_MAP_*_ELEM and BPF_MAP_GET_NEXT_KEY - commands */ - __u32 map_fd; - __aligned_u64 key; + struct { /* Used by BPF_MAP_*_ELEM and BPF_MAP_GET_NEXT_KEY commands */ + uint32_t map_fd; + uint64_t alignas(8) key; union { - __aligned_u64 value; - __aligned_u64 next_key; + uint64_t alignas(8) value; + uint64_t alignas(8) next_key; }; - __u64 flags; + uint64_t flags; }; struct { /* Used by BPF_PROG_LOAD */ - __u32 prog_type; - __u32 insn_cnt; - __aligned_u64 insns; /* \(aqconst struct bpf_insn *\(aq */ - __aligned_u64 license; /* \(aqconst char *\(aq */ - __u32 log_level; /* verbosity level of verifier */ - __u32 log_size; /* size of user buffer */ - __aligned_u64 log_buf; /* user supplied \(aqchar *\(aq - buffer */ - __u32 kern_version; - /* checked when prog_type=kprobe - (since Linux 4.1) */ + uint32_t prog_type; + uint32_t insn_cnt; + uint64_t alignas(8) insns; /* \(aqconst struct bpf_insn *\(aq */ + uint64_t alignas(8) license; /* \(aqconst char *\(aq */ + uint32_t log_level; /* verbosity level of verifier */ + uint32_t log_size; /* size of user buffer */ + uint64_t alignas(8) log_buf; /* user supplied \(aqchar *\(aq + buffer */ + uint32_t kern_version; + /* checked when prog_type=kprobe + (since Linux 4.1) */ .\" commit 2541517c32be2531e0da59dfd7efc1ce844644f5 }; -} __attribute__((aligned(8))); +}; .EE .in .\"