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=-6.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 0C467FC619F for ; Fri, 8 Nov 2019 22:40:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C45E6214DA for ; Fri, 8 Nov 2019 22:40:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="e8PQYvQG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731569AbfKHWkR (ORCPT ); Fri, 8 Nov 2019 17:40:17 -0500 Received: from mail-qk1-f193.google.com ([209.85.222.193]:47097 "EHLO mail-qk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731470AbfKHWkQ (ORCPT ); Fri, 8 Nov 2019 17:40:16 -0500 Received: by mail-qk1-f193.google.com with SMTP id h15so6708385qka.13; Fri, 08 Nov 2019 14:40:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=fu78PzF9UWPSdHn2CMCZAnQUPRcI3AzWHQi4lBbBThQ=; b=e8PQYvQG/kg45MrxHc1qp5BQ+WKBuRec229TO0CQ5dNPCLp94/DFGaEwiKtyu6yLuc NNsFtUeOoCH6AQKh/ezEjwZbiiZujHFMgq8yV5PIzph0C+ASM0ygSuGjxJcIf2vWE1u+ KjsdURSbfUJ0xaCSE9os5VJlil2fLJRL1FwbLIw/I3R9ECgUERA8wXzTU0odaPRk1SLE tLZMln4ECp0QvViwkXFGlQOmrOM9cHnbfsBPhsI5Ys9mrBsSx3jfIw5Ywa+ncq3s19sg c4iecKV8pDlDb0OCP2rnZfbiPsPJFfXE0ou+TnHfq7CoCwkzauTiD+rMMSHlExEuzW/e IR/A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=fu78PzF9UWPSdHn2CMCZAnQUPRcI3AzWHQi4lBbBThQ=; b=gxHeGYm/oBFiXbfiU2nYVIFArlmdHjEtNnE4LqIHhEU6osDe1/zcpnBm/PYDBbewD0 lY1zVxBv/cR6PvhMQBVOMB/n/SO95wD7pzALzzZKFurZV/5qp82dYKaVKCN2hAfxj/93 Jco1E/h14N0hxLIi8og9qD6nctVkUr4yUdwp8NsXFFeQnOeH1PiH5j7C4EkxkX8GyxBp fHTUl7Q1KrU4FTfBEnJrrHMYiQDNk+KzHkjneauBXJZ9EaejPR0QL3VlD49vv2bqffVi 2lN/Du9iZGCZbLWQnwJMhEwZGLOE4xA3CyGpKk8VapZO8eB2LB8IkgC3lYB7EAQgheo5 YdNg== X-Gm-Message-State: APjAAAU88BdHDZMzbordxrUe2anw9kwr8WAIzNwRk8aClQkULCDBpX0/ qz9YLBpD9+DFXpX85PI5SN5Jx6sD2S5SlAJcF0g= X-Google-Smtp-Source: APXvYqyP4Tsa9n6t2AV3DdnCfjbvh68e09/rY/xyk1hKTPhdCviFy91z4RXN/MU0jW/baiF9RasRJW83xQVgW9nA1TE= X-Received: by 2002:a05:620a:1011:: with SMTP id z17mr11612141qkj.39.1573252815442; Fri, 08 Nov 2019 14:40:15 -0800 (PST) MIME-Version: 1.0 References: <157324878503.910124.12936814523952521484.stgit@toke.dk> <157324878624.910124.5124587166846797199.stgit@toke.dk> In-Reply-To: <157324878624.910124.5124587166846797199.stgit@toke.dk> From: Andrii Nakryiko Date: Fri, 8 Nov 2019 14:40:04 -0800 Message-ID: Subject: Re: [PATCH bpf-next v2 1/6] libbpf: Unpin auto-pinned maps if loading fails To: =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= Cc: Daniel Borkmann , Alexei Starovoitov , Martin KaFai Lau , Song Liu , Yonghong Song , Jesper Dangaard Brouer , David Miller , Networking , bpf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, Nov 8, 2019 at 1:33 PM Toke H=C3=B8iland-J=C3=B8rgensen wrote: > > From: Toke H=C3=B8iland-J=C3=B8rgensen > > Since the automatic map-pinning happens during load, it will leave pinned > maps around if the load fails at a later stage. Fix this by unpinning any > pinned maps on cleanup. To avoid unpinning pinned maps that were reused > rather than newly pinned, add a new boolean property on struct bpf_map to > keep track of whether that map was reused or not; and only unpin those ma= ps > that were not reused. > > Fixes: 57a00f41644f ("libbpf: Add auto-pinning of maps when loading BPF o= bjects") > Acked-by: Song Liu > Signed-off-by: Toke H=C3=B8iland-J=C3=B8rgensen > --- > tools/lib/bpf/libbpf.c | 16 +++++++++++++--- > 1 file changed, 13 insertions(+), 3 deletions(-) > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index be4af95d5a2c..cea61b2ec9d3 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -229,6 +229,7 @@ struct bpf_map { > enum libbpf_map_type libbpf_type; > char *pin_path; > bool pinned; > + bool was_reused; nit: just reused, similar to pinned? > }; > > struct bpf_secdata { > @@ -1995,6 +1996,7 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd) > map->def.map_flags =3D info.map_flags; > map->btf_key_type_id =3D info.btf_key_type_id; > map->btf_value_type_id =3D info.btf_value_type_id; > + map->was_reused =3D true; > > return 0; > > @@ -4007,15 +4009,18 @@ bpf_object__open_buffer(const void *obj_buf, size= _t obj_buf_sz, > return bpf_object__open_mem(obj_buf, obj_buf_sz, &opts); > } > > -int bpf_object__unload(struct bpf_object *obj) > +static int __bpf_object__unload(struct bpf_object *obj, bool unpin) > { > size_t i; > > if (!obj) > return -EINVAL; > > - for (i =3D 0; i < obj->nr_maps; i++) > + for (i =3D 0; i < obj->nr_maps; i++) { > zclose(obj->maps[i].fd); > + if (unpin && obj->maps[i].pinned && !obj->maps[i].was_reu= sed) > + bpf_map__unpin(&obj->maps[i], NULL); > + } > > for (i =3D 0; i < obj->nr_programs; i++) > bpf_program__unload(&obj->programs[i]); > @@ -4023,6 +4028,11 @@ int bpf_object__unload(struct bpf_object *obj) > return 0; > } > > +int bpf_object__unload(struct bpf_object *obj) > +{ > + return __bpf_object__unload(obj, false); > +} > + > int bpf_object__load_xattr(struct bpf_object_load_attr *attr) > { > struct bpf_object *obj; > @@ -4047,7 +4057,7 @@ int bpf_object__load_xattr(struct bpf_object_load_a= ttr *attr) > > return 0; > out: > - bpf_object__unload(obj); > + __bpf_object__unload(obj, true); giving this is the only (special) case of auto-unpinning auto-pinned maps, why not do a trivial loop here, instead of having this extra unpin flag and extra __bpf_object__unload function? > pr_warn("failed to load object '%s'\n", obj->path); > return err; > } >