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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D0429EE4993 for ; Mon, 21 Aug 2023 17:16:51 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qY8Vc-0000mu-0D; Mon, 21 Aug 2023 13:16:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qY8VU-0000mh-4r for qemu-devel@nongnu.org; Mon, 21 Aug 2023 13:16:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qY8VR-00005w-Jd for qemu-devel@nongnu.org; Mon, 21 Aug 2023 13:15:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1692638156; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8olqO7ZvdKc07kSyKxloCofZ5Rm+dvTQOxgwYQqHB2M=; b=SXsmD9LiLXz59MeMTwFdm2Bo2BsE7D47TuykxwLucmFlWDNR1VvJ7C+tmCUqN6hRzHgzVA 0UC2g1svUM/Bb/zK41cRbTn7ld6pm0GEdJOL2YIUd4BZzmrJN60+OmkWzZE35C2AtrHOMj uSdLRX4RS3EOoQZNLRFUwJoZD8kqkzE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-260-CgHAJ1AjNRK-89BBv0-Zrw-1; Mon, 21 Aug 2023 13:15:54 -0400 X-MC-Unique: CgHAJ1AjNRK-89BBv0-Zrw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1E78D8D40A2; Mon, 21 Aug 2023 17:15:54 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.86]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F10CD492C14; Mon, 21 Aug 2023 17:15:53 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id E58DB21E690D; Mon, 21 Aug 2023 19:15:52 +0200 (CEST) From: Markus Armbruster To: Andrew Melnichenko Cc: Markus Armbruster , jasowang@redhat.com, mst@redhat.com, eblake@redhat.com, berrange@redhat.com, qemu-devel@nongnu.org, yuri.benditovich@daynix.com, yan@daynix.com Subject: Re: [PATCH v5 4/5] qmp: Added new command to retrieve eBPF blob. References: <20230802204125.33688-1-andrew@daynix.com> <20230802204125.33688-5-andrew@daynix.com> <87sf8yx7qa.fsf@pond.sub.org> Date: Mon, 21 Aug 2023 19:15:52 +0200 In-Reply-To: (Andrew Melnichenko's message of "Tue, 8 Aug 2023 20:43:36 +0300") Message-ID: <87pm3g8gfr.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Andrew Melnichenko writes: > Hi all, > Thanks for the comments - I'll update and send new patches. > > On Sat, Aug 5, 2023 at 10:34=E2=80=AFAM Markus Armbruster wrote: >> >> Andrew Melnychenko writes: >> >> > Now, the binary objects may be retrieved by id. >> > It would require for future qmp commands that may require specific >> > eBPF blob. >> > >> > Added command "request-ebpf". This command returns >> > eBPF program encoded base64. The program taken from the >> > skeleton and essentially is an ELF object that can be >> > loaded in the future with libbpf. >> > >> > The reason to use the command to provide the eBPF object >> > instead of a separate artifact was to avoid issues related >> > to finding the eBPF itself. eBPF object is an ELF binary >> > that contains the eBPF program and eBPF map description(BTF). >> > Overall, eBPF object should contain the program and enough >> > metadata to create/load eBPF with libbpf. As the eBPF >> > maps/program should correspond to QEMU, the eBPF can't >> > be used from different QEMU build. >> > >> > The first solution was a helper that comes with QEMU >> > and loads appropriate eBPF objects. And the issue is >> > to find a proper helper if the system has several >> > different QEMUs installed and/or built from the source, >> > which helpers may not be compatible. >> > >> > Another issue is QEMU updating while there is a running >> > QEMU instance. With an updated helper, it may not be >> > possible to hotplug virtio-net device to the already >> > running QEMU. Overall, requesting the eBPF object from >> > QEMU itself solves possible failures with acceptable effort. >> > >> > Links: >> > [PATCH 3/5] qmp: Added the helper stamp check. >> > https://lore.kernel.org/all/20230219162100.174318-4-andrew@daynix.com/ >> > >> > Signed-off-by: Andrew Melnychenko >> > --- >> >> [...] >> >> > diff --git a/qapi/ebpf.json b/qapi/ebpf.json >> > new file mode 100644 >> > index 00000000000..40851f8c177 >> > --- /dev/null >> > +++ b/qapi/ebpf.json [...] >> > +## >> > +# @request-ebpf: >> > +# >> > +# Returns eBPF object that can be loaded with libbpf. >> > +# Management applications (g.e. libvirt) may load it and pass file >> > +# descriptors to QEMU. Which allows running QEMU without BPF capabili= ties. >> > +# It's crucial that eBPF program/map is compatible with QEMU, so it's >> > +# provided through QMP. >> > +# >> > +# Returns: RSS eBPF object encoded in base64. >> >> What does "RSS" mean? > > RSS - Receive-side Scaling. Suggest to use something like "receive-side scaling (RSS)" the first time. You could also put a general introduction right below the header, like ## # =3D eBPF Objects # # Text goes here ## This is not a demand. [...]