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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 ED35AC2BAEE for ; Tue, 24 Mar 2020 18:53:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BCED62076E for ; Tue, 24 Mar 2020 18:53:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585076032; bh=zbUjVqmOQpHgft4VC/u9Z+h3ICSYIu6L90BtbphGNPA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=Jy9KfqRCOt4lo3PcbrZuZYqX4FJjyjTyAmekEypRVe5UKSTCtsoDC5rd7+HwR8MW8 H7uN/EyVzk5/YI3NHlJf0aXYhcY83+LHoMs0TkNs7JXuqYH9HT7dt8lga/SdqmqGpf +rL27k+DSm05XVyAkDPO4xWkZvSjLkT5G5abxs6M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727567AbgCXSxw (ORCPT ); Tue, 24 Mar 2020 14:53:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:59090 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727379AbgCXSxw (ORCPT ); Tue, 24 Mar 2020 14:53:52 -0400 Received: from kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com (unknown [163.114.132.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 40D5B2074D; Tue, 24 Mar 2020 18:53:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585076031; bh=zbUjVqmOQpHgft4VC/u9Z+h3ICSYIu6L90BtbphGNPA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=hYFW9dgn4FhW7wsomQPnDyFo1ndJIRyy/GrXFbGR1cMpHFb1A3U5iBg6hKB4joVq7 URoi5mmYwdT+ZRaSNM7KIGwUdexvd8IqCUaPJuk9vuYaRNy1y+crtDvUyn4TT4+yZ4 x/GnvREx191KhJcE55V7oekwk9p1YIt9lb4n/DNc= Date: Tue, 24 Mar 2020 11:53:49 -0700 From: Jakub Kicinski To: Toke =?UTF-8?B?SMO4aWxhbmQtSsO4cmdlbnNlbg==?= Cc: Andrii Nakryiko , John Fastabend , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , "David S. Miller" , Jesper Dangaard Brouer , Lorenz Bauer , Andrey Ignatov , Networking , bpf Subject: Re: [PATCH bpf-next 1/4] xdp: Support specifying expected existing program when attaching XDP Message-ID: <20200324115349.6447f99b@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <87tv2e10ly.fsf@toke.dk> References: <158462359206.164779.15902346296781033076.stgit@toke.dk> <158462359315.164779.13931660750493121404.stgit@toke.dk> <20200319155236.3d8537c5@kicinski-fedora-PC1C0HJN> <875zez76ph.fsf@toke.dk> <20200320103530.2853c573@kicinski-fedora-PC1C0HJN> <5e750bd4ebf8d_233f2ab4c81425c4ce@john-XPS-13-9370.notmuch> <87tv2f48lp.fsf@toke.dk> <87h7ye3mf3.fsf@toke.dk> <87tv2e10ly.fsf@toke.dk> MIME-Version: 1.0 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 Tue, 24 Mar 2020 11:57:45 +0100 Toke H=C3=B8iland-J=C3=B8rgensen wrote: > > If everyone is using libbpf, does kernel system (bpf syscall vs > > netlink) matter all that much? =20 >=20 > This argument works the other way as well, though: If libbpf can > abstract the subsystem differences and provide a consistent interface to > "the BPF world", why does BPF need to impose its own syscall API on the > networking subsystem? Hitting the nail on the head there, again :) Once upon a time when we were pushing for libbpf focus & unification, one of my main motivations was that a solid library that most people use give us the ability to provide user space abstractions. As much as adding new kernel interfaces "to rule them all" is fun, it has a real cost.