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=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8E7CCC4320A for ; Fri, 30 Jul 2021 06:54:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 74BB160F9B for ; Fri, 30 Jul 2021 06:54:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237735AbhG3GyS (ORCPT ); Fri, 30 Jul 2021 02:54:18 -0400 Received: from smtp-fw-80007.amazon.com ([99.78.197.218]:62109 "EHLO smtp-fw-80007.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237702AbhG3GyS (ORCPT ); Fri, 30 Jul 2021 02:54:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.co.jp; i=@amazon.co.jp; q=dns/txt; s=amazon201209; t=1627628055; x=1659164055; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=eJIXvXemTzZ+Jf6w2MSZ7dbahsya+/cy1Azgbxx/z6g=; b=t1K5GvKOHggxJwadz2LROXOh6dzEAdXsYizvE8AZ2wVltBr/wW02cC4I wmSJiXAl3l70m5BVldDfzaTm3IGZzrwbjaErPcOMUvl0PHYkPPiBh3fm8 FVLlte3QuWs3oNZDGU6dQrow2cYNDJX64gqI9urTx5k3gVqKiQVxYKqTQ g=; X-IronPort-AV: E=Sophos;i="5.84,281,1620691200"; d="scan'208";a="15892312" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-1e-27fb8269.us-east-1.amazon.com) ([10.25.36.210]) by smtp-border-fw-80007.pdx80.corp.amazon.com with ESMTP; 30 Jul 2021 06:54:13 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1e-27fb8269.us-east-1.amazon.com (Postfix) with ESMTPS id 46D24A1C46; Fri, 30 Jul 2021 06:54:09 +0000 (UTC) Received: from EX13D04ANC001.ant.amazon.com (10.43.157.89) by EX13MTAUWB001.ant.amazon.com (10.43.161.207) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Fri, 30 Jul 2021 06:54:08 +0000 Received: from 88665a182662.ant.amazon.com (10.43.162.75) by EX13D04ANC001.ant.amazon.com (10.43.157.89) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Fri, 30 Jul 2021 06:54:03 +0000 From: Kuniyuki Iwashima To: CC: , , , , , , , , , , , , , Subject: Re: [PATCH bpf-next 1/2] bpf: af_unix: Implement BPF iterator for UNIX domain socket. Date: Fri, 30 Jul 2021 15:53:59 +0900 Message-ID: <20210730065359.43302-1-kuniyu@amazon.co.jp> X-Mailer: git-send-email 2.30.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.162.75] X-ClientProxiedBy: EX13D25UWC003.ant.amazon.com (10.43.162.129) To EX13D04ANC001.ant.amazon.com (10.43.157.89) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Yonghong Song Date: Thu, 29 Jul 2021 23:24:41 -0700 > On 7/29/21 4:36 PM, Kuniyuki Iwashima wrote: > > This patch implements the BPF iterator for the UNIX domain socket. > > > > Currently, the batch optimization introduced for the TCP iterator in the > > commit 04c7820b776f ("bpf: tcp: Bpf iter batching and lock_sock") is not > > applied. It will require replacing the big lock for the hash table with > > small locks for each hash list not to block other processes. > > Thanks for the contribution. The patch looks okay except > missing seq_ops->stop implementation, see below for more explanation. > > > > > Signed-off-by: Kuniyuki Iwashima > > --- > > include/linux/btf_ids.h | 3 +- > > net/unix/af_unix.c | 78 +++++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 80 insertions(+), 1 deletion(-) > > > > diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h > > index 57890b357f85..bed4b9964581 100644 > > --- a/include/linux/btf_ids.h > > +++ b/include/linux/btf_ids.h > > @@ -172,7 +172,8 @@ extern struct btf_id_set name; > > BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP_TW, tcp_timewait_sock) \ > > BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP6, tcp6_sock) \ > > BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP, udp_sock) \ > > - BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) > > + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) \ > > + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UNIX, unix_sock) > > > > enum { > > #define BTF_SOCK_TYPE(name, str) name, > > diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c > > index 89927678c0dc..d45ad87e3a49 100644 > > --- a/net/unix/af_unix.c > > +++ b/net/unix/af_unix.c > > @@ -113,6 +113,7 @@ > > #include > > #include > > #include > > +#include > > > > #include "scm.h" > > > > @@ -2935,6 +2936,49 @@ static const struct seq_operations unix_seq_ops = { > > .stop = unix_seq_stop, > > .show = unix_seq_show, > > }; > > + > > +#ifdef CONFIG_BPF_SYSCALL > > +struct bpf_iter__unix { > > + __bpf_md_ptr(struct bpf_iter_meta *, meta); > > + __bpf_md_ptr(struct unix_sock *, unix_sk); > > + uid_t uid __aligned(8); > > +}; > > + > > +static int unix_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta, > > + struct unix_sock *unix_sk, uid_t uid) > > +{ > > + struct bpf_iter__unix ctx; > > + > > + meta->seq_num--; /* skip SEQ_START_TOKEN */ > > + ctx.meta = meta; > > + ctx.unix_sk = unix_sk; > > + ctx.uid = uid; > > + return bpf_iter_run_prog(prog, &ctx); > > +} > > + > > +static int bpf_iter_unix_seq_show(struct seq_file *seq, void *v) > > +{ > > + struct bpf_iter_meta meta; > > + struct bpf_prog *prog; > > + struct sock *sk = v; > > + uid_t uid; > > + > > + if (v == SEQ_START_TOKEN) > > + return 0; > > + > > + uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)); > > + meta.seq = seq; > > + prog = bpf_iter_get_info(&meta, false); > > + return unix_prog_seq_show(prog, &meta, v, uid); > > +} > > + > > +static const struct seq_operations bpf_iter_unix_seq_ops = { > > + .start = unix_seq_start, > > + .next = unix_seq_next, > > + .stop = unix_seq_stop, > > Although it is not required for /proc/net/unix, we should still > implement bpf_iter version of seq_ops->stop here. The main purpose > of bpf_iter specific seq_ops->stop is to call bpf program one > more time after ALL elements have been traversed. Such > functionality is implemented in all other bpf_iter variants. Thanks for your review! I will implement the extra call in the next spin. Just out of curiosity, is there a specific use case for the last call?