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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 AFE18C433DF for ; Mon, 15 Jun 2020 09:04:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 896CB2065F for ; Mon, 15 Jun 2020 09:04:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Qlk2SwuY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729073AbgFOJEn (ORCPT ); Mon, 15 Jun 2020 05:04:43 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:53046 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728411AbgFOJEm (ORCPT ); Mon, 15 Jun 2020 05:04:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592211881; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=eqCxKohGvLbDOAcYvRzfZ70rZCgIvTAgDpyXvxo9QZw=; b=Qlk2SwuYJP++GBzymzqRPg6oV/vIwnCSPsTpT2RzsbKO/qx80ZlxXrMAeMdSMY3ga3S96Z tIAlSB1aEihqCFtrF9BvLaUzVkqaOE2YhSWhpIu6blcnyyfbetIB3rwb2OxZqeVsJljT9X Tk+f0kybCccmgHkpEqekbOnJ4uL+z4c= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-203-m0Iv62gKNQKbCAeY85jZ2w-1; Mon, 15 Jun 2020 05:04:39 -0400 X-MC-Unique: m0Iv62gKNQKbCAeY85jZ2w-1 Received: by mail-ed1-f69.google.com with SMTP id dn27so4685724edb.15 for ; Mon, 15 Jun 2020 02:04:39 -0700 (PDT) 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:in-reply-to:references:date :message-id:mime-version; bh=eqCxKohGvLbDOAcYvRzfZ70rZCgIvTAgDpyXvxo9QZw=; b=jllMJ40Y44bxLbCpNipjQMpYguxACVFmldBQ9snT0Mf/XiKcGl51gvZlg2MaPUKcvG YS0WrL0eXWpAITTun5hD/MXYTvaIjm6vFOk5Q+Ai+eBzgPm5isXZBy1fUVdCVsEqsOCp o7VRyx+kwxcMLwCgKJnAmcFdKanZ1vNzKwSHDP3tZd1pjAfkgSrpsmugFcQWIW2sxPpt PRVc8sEVpg/NvfWZHtQxI0gNZHV8yOqPyyvSnZLI7UhdxK6C+ThG9S57qrZx1dUi9DZF iD1v09pR1irA4ZkFXT+I16ozY9QUJyMFd0G1UoEnMFZbGiaqFTcmYANNgkLJQBL/o+YD Z9LA== X-Gm-Message-State: AOAM531wakFsF4B2qKCDvoNhVahc1U+WFJNHg2fcc/8vjmCADWYO/qf9 W8wb5k9+QW/OXfIS72Gw2XUWHFIkqt3xBktnB3Jo80FYNLa+kPMHY+u752l6OQmkJEK77abIcRP OULhQALahMkz/ X-Received: by 2002:a50:f094:: with SMTP id v20mr22603475edl.77.1592211878375; Mon, 15 Jun 2020 02:04:38 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxQV9d8O1teV5U813ms9N4ToB2nzLDvlhioQHU+f4HBdn9vWHWBNEJsAmukYldRqTxWeB+HPA== X-Received: by 2002:a50:f094:: with SMTP id v20mr22603450edl.77.1592211878095; Mon, 15 Jun 2020 02:04:38 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk ([2a0c:4d80:42:443::2]) by smtp.gmail.com with ESMTPSA id z10sm8653487ejb.9.2020.06.15.02.04.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Jun 2020 02:04:36 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 9883D1814F7; Mon, 15 Jun 2020 11:04:34 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Arnaldo Carvalho de Melo , Andrii Nakryiko Cc: Alexei Starovoitov , Andrii Nakryiko , bpf , Networking , Alexei Starovoitov , Daniel Borkmann , Kernel Team , Hao Luo , Song Liu , Quentin Monnet Subject: Re: [RFC PATCH bpf-next 8/8] tools/bpftool: show PIDs with FDs open against BPF map/prog/link/btf In-Reply-To: <20200613221419.GB7488@kernel.org> References: <20200612223150.1177182-1-andriin@fb.com> <20200612223150.1177182-9-andriin@fb.com> <20200613034507.wjhd4z6dsda3pz7c@ast-mbp> <20200613221419.GB7488@kernel.org> X-Clacks-Overhead: GNU Terry Pratchett Date: Mon, 15 Jun 2020 11:04:34 +0200 Message-ID: <87pna01yzh.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Arnaldo Carvalho de Melo writes: > Em Fri, Jun 12, 2020 at 10:57:59PM -0700, Andrii Nakryiko escreveu: >> On Fri, Jun 12, 2020 at 8:45 PM Alexei Starovoitov >> wrote: >> > >> > On Fri, Jun 12, 2020 at 03:31:50PM -0700, Andrii Nakryiko wrote: >> > > Add bpf_iter-based way to find all the processes that hold open FDs against >> > > BPF object (map, prog, link, btf). Add new flag (-o, for "ownership", given >> > > -p is already taken) to trigger collection and output of these PIDs. >> > > >> > > Sample output for each of 4 BPF objects: >> > > >> > > $ sudo ./bpftool -o prog show >> > > 1992: cgroup_skb name egress_alt tag 9ad187367cf2b9e8 gpl >> > > loaded_at 2020-06-12T14:18:10-0700 uid 0 >> > > xlated 48B jited 59B memlock 4096B map_ids 2074 >> > > btf_id 460 >> > > pids: 913709,913732,913733,913734 >> > > 2062: cgroup_device tag 8c42dee26e8cd4c2 gpl >> > > loaded_at 2020-06-12T14:37:52-0700 uid 0 >> > > xlated 648B jited 409B memlock 4096B >> > > pids: 1 >> > > >> > > $ sudo ./bpftool -o map show >> > > 2074: array name test_cgr.bss flags 0x400 >> > > key 4B value 8B max_entries 1 memlock 8192B >> > > btf_id 460 >> > > pids: 913709,913732,913733,913734 >> > > >> > > $ sudo ./bpftool -o link show >> > > 82: cgroup prog 1992 >> > > cgroup_id 0 attach_type egress >> > > pids: 913709,913732,913733,913734 >> > > 86: cgroup prog 1992 >> > > cgroup_id 0 attach_type egress >> > > pids: 913709,913732,913733,913734 >> > >> > This is awesome. > > Indeed. > >> Thanks. >> >> > >> > Why extra flag though? I think it's so useful that everyone would want to see > > Agreed. > >> No good reason apart from "being safe by default". If turned on by >> default, bpftool would need to probe for bpf_iter support first. I can >> add probing and do this by default. > > I think this is the way to go. +1 And also +1 on the awesomeness of this feature! :) -Toke