From patchwork Tue Mar 12 11:36:41 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 13589866 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 0F0CDC54E58 for ; Tue, 12 Mar 2024 11:38:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rk0Rz-0007a1-Q0; Tue, 12 Mar 2024 07:37:45 -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 1rk0RV-0007Im-BQ for qemu-devel@nongnu.org; Tue, 12 Mar 2024 07:37:14 -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 1rk0RS-0003Dj-AM for qemu-devel@nongnu.org; Tue, 12 Mar 2024 07:37:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710243427; 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=rTtijyupYiiTV5NIPOZ/TQjw6REJpyYtK3TlVNAoSkg=; b=BbQnBqwMEhNo23Tv80Ym3T5aspV9MdDtdhrmbxFj2BJd3TVHnynvLhLDubKWqOcCM9kqgY MlmezkZ59oSQtQ5VOeTvhlNVhORQd0MF3GVbxvTP+K0yJIBvvxs4zOaSGZ2r00MTL28/1z God5M9by4wAExkpGHaCn55iI132r6+s= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-568-KYbJ8U10MPugjQsVagJPNw-1; Tue, 12 Mar 2024 07:37:05 -0400 X-MC-Unique: KYbJ8U10MPugjQsVagJPNw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BCD09101A56C; Tue, 12 Mar 2024 11:37:04 +0000 (UTC) Received: from localhost.localdomain (unknown [10.72.112.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id A4F86492BC6; Tue, 12 Mar 2024 11:37:02 +0000 (UTC) From: Jason Wang To: qemu-devel@nongnu.org, peter.maydell@linaro.org Cc: Andrew Melnychenko , Jason Wang Subject: [PULL 7/8] qmp: Added new command to retrieve eBPF blob. Date: Tue, 12 Mar 2024 19:36:41 +0800 Message-ID: <20240312113642.36862-8-jasowang@redhat.com> In-Reply-To: <20240312113642.36862-1-jasowang@redhat.com> References: <20240312113642.36862-1-jasowang@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 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: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.687, 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, T_SCC_BODY_TEXT_LINE=-0.01 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 | 69 +++++++++++++++++++++++++++++++++++++++++++ ebpf/ebpf.h | 29 ++++++++++++++++++ ebpf/ebpf_rss.c | 11 ++++--- ebpf/meson.build | 2 +- ebpf/trace.h | 1 - qapi/ebpf.json | 66 +++++++++++++++++++++++++++++++++++++++++ qapi/meson.build | 1 + qapi/qapi-schema.json | 1 + 8 files changed, 172 insertions(+), 8 deletions(-) create mode 100644 ebpf/ebpf.c create mode 100644 ebpf/ebpf.h delete mode 100644 ebpf/trace.h create mode 100644 qapi/ebpf.json diff --git a/ebpf/ebpf.c b/ebpf/ebpf.c new file mode 100644 index 0000000000..2d73beb479 --- /dev/null +++ b/ebpf/ebpf.c @@ -0,0 +1,69 @@ +/* + * QEMU eBPF binary declaration routine. + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Andrew Melnychenko + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "qemu/queue.h" +#include "qapi/error.h" +#include "qapi/qapi-commands-ebpf.h" +#include "ebpf/ebpf.h" + +typedef struct ElfBinaryDataEntry { + int id; + const void *data; + size_t datalen; + + QSLIST_ENTRY(ElfBinaryDataEntry) node; +} ElfBinaryDataEntry; + +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 0000000000..378d4e9c70 --- /dev/null +++ b/ebpf/ebpf.h @@ -0,0 +1,29 @@ +/* + * QEMU eBPF binary declaration routine. + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Andrew Melnychenko + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef EBPF_H +#define EBPF_H + + +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 150aa40813..2e506f9743 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 @@ -21,7 +23,7 @@ #include "ebpf/ebpf_rss.h" #include "ebpf/rss.bpf.skeleton.h" -#include "trace.h" +#include "ebpf/ebpf.h" void ebpf_rss_init(struct EBPFRSSContext *ctx) { @@ -53,21 +55,18 @@ static bool ebpf_rss_mmap(struct EBPFRSSContext *ctx) PROT_READ | PROT_WRITE, MAP_SHARED, ctx->map_configuration, 0); if (ctx->mmap_configuration == MAP_FAILED) { - trace_ebpf_error("eBPF RSS", "can not mmap eBPF configuration array"); return false; } ctx->mmap_toeplitz_key = mmap(NULL, qemu_real_host_page_size(), PROT_READ | PROT_WRITE, MAP_SHARED, ctx->map_toeplitz_key, 0); if (ctx->mmap_toeplitz_key == MAP_FAILED) { - trace_ebpf_error("eBPF RSS", "can not mmap eBPF toeplitz key"); goto toeplitz_fail; } ctx->mmap_indirections_table = mmap(NULL, qemu_real_host_page_size(), PROT_READ | PROT_WRITE, MAP_SHARED, ctx->map_indirections_table, 0); if (ctx->mmap_indirections_table == MAP_FAILED) { - trace_ebpf_error("eBPF RSS", "can not mmap eBPF indirection table"); goto indirection_fail; } @@ -109,14 +108,12 @@ bool ebpf_rss_load(struct EBPFRSSContext *ctx) rss_bpf_ctx = rss_bpf__open(); if (rss_bpf_ctx == NULL) { - trace_ebpf_error("eBPF RSS", "can not open eBPF RSS object"); goto error; } bpf_program__set_type(rss_bpf_ctx->progs.tun_rss_steering_prog, BPF_PROG_TYPE_SOCKET_FILTER); if (rss_bpf__load(rss_bpf_ctx)) { - trace_ebpf_error("eBPF RSS", "can not load RSS program"); goto error; } @@ -261,3 +258,5 @@ 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 2f627d6c7d..c5bf9295a2 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/ebpf/trace.h b/ebpf/trace.h deleted file mode 100644 index abefc46ab1..0000000000 --- a/ebpf/trace.h +++ /dev/null @@ -1 +0,0 @@ -#include "trace/trace-ebpf.h" diff --git a/qapi/ebpf.json b/qapi/ebpf.json new file mode 100644 index 0000000000..f413d00154 --- /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: 9.0 +## +{ '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: 9.0 +## +{ '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: 9.0 +## +{ 'command': 'request-ebpf', + 'data': { 'id': 'EbpfProgramID' }, + 'returns': 'EbpfObject', + 'if': 'CONFIG_EBPF' } diff --git a/qapi/meson.build b/qapi/meson.build index f81a37565c..375d564277 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 c01ec335e6..8304d45625 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' }