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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 1216DC4338F for ; Sat, 7 Aug 2021 12:56:07 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 63A2260EBC for ; Sat, 7 Aug 2021 12:56:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 63A2260EBC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:49138 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mCLrx-0001aT-6E for qemu-devel@archiver.kernel.org; Sat, 07 Aug 2021 08:56:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52478) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mCLqe-0000tR-0m for qemu-devel@nongnu.org; Sat, 07 Aug 2021 08:54:44 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42432) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mCLqc-00008e-8c for qemu-devel@nongnu.org; Sat, 07 Aug 2021 08:54:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628340881; 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=qlf1CxCABtK+0PWlbOiWO0C3oeizPXzfhL0bczRuSpI=; b=K4CPVSwVF11tov3iBl3GayZtilB0ZkobenZKNn5mZQ6W+xnBET/mYehk41Bz9Ey7u0WofS hY8tLus1uFsx06HrKr8DKv7T0BwE/T3tdKZC2sdfg4L5YcScvM/uoJA6HqWdAJbP/GBLvL Tc+HY33sBNQTTC/TspdE3cSPnaqJQz8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-135-4bPBXFHsMcSL2pw7brIW6A-1; Sat, 07 Aug 2021 08:54:40 -0400 X-MC-Unique: 4bPBXFHsMcSL2pw7brIW6A-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0BE55107ACF5; Sat, 7 Aug 2021 12:54:39 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-112-12.ams2.redhat.com [10.36.112.12]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 263CA5B826; Sat, 7 Aug 2021 12:54:35 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id AA25011380A0; Sat, 7 Aug 2021 14:54:33 +0200 (CEST) From: Markus Armbruster To: Andrew Melnychenko Subject: Re: [PATCH 5/5] qmp: Added qemu-ebpf-rss-path command. References: <20210713153758.323614-1-andrew@daynix.com> <20210713153758.323614-6-andrew@daynix.com> Date: Sat, 07 Aug 2021 14:54:33 +0200 In-Reply-To: <20210713153758.323614-6-andrew@daynix.com> (Andrew Melnychenko's message of "Tue, 13 Jul 2021 18:37:58 +0300") Message-ID: <87y29dct4m.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=armbru@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Received-SPF: pass client-ip=216.205.24.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.7, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: berrange@redhat.com, mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org, yuri.benditovich@daynix.com, yan@daynix.com, eblake@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Andrew Melnychenko writes: > New qmp command to query ebpf helper. > It's crucial that qemu and helper are in sync and in touch. > Technically helper should pass eBPF fds that qemu may accept. > And different qemu's builds may have different eBPF programs and helpers. > Qemu returns helper that should "fit" to virtio-net. > > Signed-off-by: Andrew Melnychenko [...] > diff --git a/qapi/misc.json b/qapi/misc.json > index 156f98203e..9aaf8fbcca 100644 > --- a/qapi/misc.json > +++ b/qapi/misc.json > @@ -519,3 +519,36 @@ > 'data': { '*option': 'str' }, > 'returns': ['CommandLineOptionInfo'], > 'allow-preconfig': true } > + > +## > +# @HelperPath: > +# > +# Name of the helper and binary location. > +## > +{ 'struct': 'HelperPath', > + 'data': {'name': 'str', 'path': 'str'} } > + > +## > +# @query-helper-paths: > +# > +# Query helper paths. Initially, this command was added for > +# qemu-ebpf-rss-helper. The qemu would check "the stamp" and > +# returns proper helper. > +# > +# Returns: list of object that contains name and path for helper. > +# > +# Since: 6.1 > +# > +# Example: > +# > +# -> { "execute": "query-helper-paths" } > +# <- { "return": [ > +# { > +# "name": "qemu-ebpf-rss-helper", > +# "path": "/usr/local/libexec/qemu-ebpf-rss-helper" > +# } > +# ] > +# } > +# > +## > +{ 'command': 'query-helper-paths', 'returns': ['HelperPath'] } Hmm. I understand the desire to help management applications to use the right helper. But I'm not sure this command is actually useful. The helper may or may not be installed at the path compiled into QEMU. What happens when you use the wrong helper? Even if we conclude this is the right approach for this helper, we still need to review the other helpers to see which of them we should have query-helper-paths cover.