From patchwork Fri Sep 8 06:45:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 13377151 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 1EE86EE57CA for ; Fri, 8 Sep 2023 06:46:36 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qeVG6-00068U-0v; Fri, 08 Sep 2023 02:46:26 -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 1qeVFq-0005Qb-4F for qemu-devel@nongnu.org; Fri, 08 Sep 2023 02:46:17 -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 1qeVFj-0003MO-IX for qemu-devel@nongnu.org; Fri, 08 Sep 2023 02:46:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694155562; 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=IQ4XP+Fso3JXRi0IK0smd/SrAOvXF67SrW0kHlSD1iY=; b=dpYuMP1a0dlRNij4QJye6s4LDXO67kxibP+zrhVpjv4v+KoNPzDuY3ycQvF1oX223ui72c vLYfhjhneaZ11a/ylb6JwHZHPqkUTrZsc8dpeiHcKEyjG6VPeZPURhQiYKXTOuPbVwLrk5 eRk0CoNOIPwjdlm2FTc7bPU0UkkYUmw= 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-154-FguFC4yrMk6tkomVATa_fg-1; Fri, 08 Sep 2023 02:45:56 -0400 X-MC-Unique: FguFC4yrMk6tkomVATa_fg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id ABECC8030B1; Fri, 8 Sep 2023 06:45:55 +0000 (UTC) Received: from localhost.localdomain (unknown [10.72.113.80]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0A7D71121314; Fri, 8 Sep 2023 06:45:53 +0000 (UTC) From: Jason Wang To: qemu-devel@nongnu.org Cc: Andrew Melnychenko , Jason Wang Subject: [PULL 16/17] qmp: Added new command to retrieve eBPF blob. Date: Fri, 8 Sep 2023 14:45:06 +0800 Message-Id: <20230908064507.14596-17-jasowang@redhat.com> In-Reply-To: <20230908064507.14596-1-jasowang@redhat.com> References: <20230908064507.14596-1-jasowang@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.133.124; envelope-from=jasowang@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_H3=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 From: Andrew Melnychenko 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 Signed-off-by: Jason Wang --- ebpf/ebpf.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++ ebpf/ebpf.h | 31 +++++++++++++++++++++++ ebpf/ebpf_rss.c | 6 +++++ ebpf/meson.build | 2 +- qapi/ebpf.json | 66 ++++++++++++++++++++++++++++++++++++++++++++++++ qapi/meson.build | 1 + qapi/qapi-schema.json | 1 + 7 files changed, 176 insertions(+), 1 deletion(-) create mode 100644 ebpf/ebpf.c create mode 100644 ebpf/ebpf.h create mode 100644 qapi/ebpf.json diff --git a/ebpf/ebpf.c b/ebpf/ebpf.c new file mode 100644 index 0000000..ea97c04 --- /dev/null +++ b/ebpf/ebpf.c @@ -0,0 +1,70 @@ +/* + * QEMU eBPF binary declaration routine. + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Andrew Melnychenko + * + * This work is licensed under the terms of the GNU GPL, version 2 or + * later. See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include "qemu/queue.h" +#include "qapi/error.h" +#include "qapi/qapi-commands-ebpf.h" +#include "ebpf/ebpf.h" + +struct ElfBinaryDataEntry { + int id; + const void *data; + size_t datalen; + + QSLIST_ENTRY(ElfBinaryDataEntry) node; +}; + +static QSLIST_HEAD(, ElfBinaryDataEntry) ebpf_elf_obj_list = + QSLIST_HEAD_INITIALIZER(); + +void ebpf_register_binary_data(int id, const void *data, size_t datalen) +{ + struct ElfBinaryDataEntry *dataentry = NULL; + + dataentry = g_new0(struct ElfBinaryDataEntry, 1); + dataentry->data = data; + dataentry->datalen = datalen; + dataentry->id = id; + + QSLIST_INSERT_HEAD(&ebpf_elf_obj_list, dataentry, node); +} + +const void *ebpf_find_binary_by_id(int id, size_t *sz, Error **errp) +{ + struct ElfBinaryDataEntry *it = NULL; + QSLIST_FOREACH(it, &ebpf_elf_obj_list, node) { + if (id == it->id) { + *sz = it->datalen; + return it->data; + } + } + + error_setg(errp, "can't find eBPF object with id: %d", id); + + return NULL; +} + +EbpfObject *qmp_request_ebpf(EbpfProgramID id, Error **errp) +{ + EbpfObject *ret = NULL; + size_t size = 0; + const void *data = ebpf_find_binary_by_id(id, &size, errp); + if (!data) { + return NULL; + } + + ret = g_new0(EbpfObject, 1); + ret->object = g_base64_encode(data, size); + + return ret; +} diff --git a/ebpf/ebpf.h b/ebpf/ebpf.h new file mode 100644 index 0000000..b6266b2 --- /dev/null +++ b/ebpf/ebpf.h @@ -0,0 +1,31 @@ +/* + * QEMU eBPF binary declaration routine. + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Andrew Melnychenko + * + * This work is licensed under the terms of the GNU GPL, version 2 or + * later. See the COPYING file in the top-level directory. + */ + +#ifndef EBPF_H +#define EBPF_H + +struct Error; + +void ebpf_register_binary_data(int id, const void *data, + size_t datalen); +const void *ebpf_find_binary_by_id(int id, size_t *sz, + struct Error **errp); + +#define ebpf_binary_init(id, fn) \ +static void __attribute__((constructor)) ebpf_binary_init_ ## fn(void) \ +{ \ + size_t datalen = 0; \ + const void *data = fn(&datalen); \ + ebpf_register_binary_data(id, data, datalen); \ +} + +#endif /* EBPF_H */ diff --git a/ebpf/ebpf_rss.c b/ebpf/ebpf_rss.c index 24bc6cc..8679dc4 100644 --- a/ebpf/ebpf_rss.c +++ b/ebpf/ebpf_rss.c @@ -13,6 +13,8 @@ #include "qemu/osdep.h" #include "qemu/error-report.h" +#include "qapi/qapi-types-misc.h" +#include "qapi/qapi-commands-ebpf.h" #include #include @@ -21,6 +23,8 @@ #include "ebpf/ebpf_rss.h" #include "ebpf/rss.bpf.skeleton.h" +#include "ebpf/ebpf.h" + #include "trace.h" void ebpf_rss_init(struct EBPFRSSContext *ctx) @@ -261,3 +265,5 @@ void ebpf_rss_unload(struct EBPFRSSContext *ctx) ctx->map_toeplitz_key = -1; ctx->map_indirections_table = -1; } + +ebpf_binary_init(EBPF_PROGRAMID_RSS, rss_bpf__elf_bytes) diff --git a/ebpf/meson.build b/ebpf/meson.build index 2f627d6..c5bf929 100644 --- a/ebpf/meson.build +++ b/ebpf/meson.build @@ -1 +1 @@ -system_ss.add(when: libbpf, if_true: files('ebpf_rss.c'), if_false: files('ebpf_rss-stub.c')) +common_ss.add(when: libbpf, if_true: files('ebpf.c', 'ebpf_rss.c'), if_false: files('ebpf_rss-stub.c')) diff --git a/qapi/ebpf.json b/qapi/ebpf.json new file mode 100644 index 0000000..ba78407 --- /dev/null +++ b/qapi/ebpf.json @@ -0,0 +1,66 @@ +# -*- Mode: Python -*- +# vim: filetype=python +# +# This work is licensed under the terms of the GNU GPL, version 2 or later. +# See the COPYING file in the top-level directory. + +## +# = eBPF Objects +# +# 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. +# +# Currently, there is a possible eBPF for receive-side scaling (RSS). +# +## + +## +# @EbpfObject: +# +# An eBPF ELF object. +# +# @object: the eBPF object encoded in base64 +# +# Since: 8.2 +## +{ 'struct': 'EbpfObject', + 'data': {'object': 'str'}, + 'if': 'CONFIG_EBPF' } + +## +# @EbpfProgramID: +# +# The eBPF programs that can be gotten with request-ebpf. +# +# @rss: Receive side scaling, technology that allows steering traffic +# between queues by calculation hash. Users may set up +# indirection table and hash/packet types configurations. Used +# with virtio-net. +# +# Since: 8.2 +## +{ 'enum': 'EbpfProgramID', + 'if': 'CONFIG_EBPF', + 'data': [ { 'name': 'rss' } ] } + +## +# @request-ebpf: +# +# Retrieve an eBPF object that can be loaded with libbpf. Management +# applications (g.e. libvirt) may load it and pass file descriptors to +# QEMU, so they can run running QEMU without BPF capabilities. +# +# @id: The ID of the program to return. +# +# Returns: eBPF object encoded in base64. +# +# Since: 8.2 +## +{ 'command': 'request-ebpf', + 'data': { 'id': 'EbpfProgramID' }, + 'returns': 'EbpfObject', + 'if': 'CONFIG_EBPF' } diff --git a/qapi/meson.build b/qapi/meson.build index 60a668b..90047da 100644 --- a/qapi/meson.build +++ b/qapi/meson.build @@ -33,6 +33,7 @@ qapi_all_modules = [ 'crypto', 'cxl', 'dump', + 'ebpf', 'error', 'introspect', 'job', diff --git a/qapi/qapi-schema.json b/qapi/qapi-schema.json index 6594afb..2c82a49 100644 --- a/qapi/qapi-schema.json +++ b/qapi/qapi-schema.json @@ -53,6 +53,7 @@ { 'include': 'char.json' } { 'include': 'dump.json' } { 'include': 'net.json' } +{ 'include': 'ebpf.json' } { 'include': 'rdma.json' } { 'include': 'rocker.json' } { 'include': 'tpm.json' }