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 99FBDC4167B for ; Mon, 11 Dec 2023 13:30:57 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rCgMh-0007MK-69; Mon, 11 Dec 2023 08:30:31 -0500 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 1rCgMe-0007KT-3q for qemu-devel@nongnu.org; Mon, 11 Dec 2023 08:30:28 -0500 Received: from mail-pl1-x631.google.com ([2607:f8b0:4864:20::631]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1rCgMR-0001zH-QY for qemu-devel@nongnu.org; Mon, 11 Dec 2023 08:30:27 -0500 Received: by mail-pl1-x631.google.com with SMTP id d9443c01a7336-1d06d4d685aso24784925ad.3 for ; Mon, 11 Dec 2023 05:30:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702301410; x=1702906210; darn=nongnu.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=w5lk0S4MKk7kTfOoLt53+VBp8ju+IsHlYguOVxO1EDI=; b=GiRzx7rPEEbVDZMluSYtdE0smk4vio46pH75f2+PHDxElDECcOHfOyKI4N2btWzT+x SaTrXZXg2+xex1FRSwS4kX4rGZ7Q0XgQdp4eqaM7TZlQKMRQwQk8VeGZwvwxX5GUzo7d ootBC4MrzkwUU1U3uM3ZJKS9ug7dppKcNIfToqLhn+ZDG2PzOaqGu8fTNddreb6ubqn5 uZjDO3BXNcPj9DtAPKijAfdAKLkA3+SSlU8YVokfbBBmKTuMi8lhnfH/hqojmX0+cLRg /PNN45J9Iz4fCFzXgcVI1EalfkpevpZnvGU9DtAYSuI/aU/v224+OR0VzZRt9RhgHhfl EBWA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702301410; x=1702906210; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=w5lk0S4MKk7kTfOoLt53+VBp8ju+IsHlYguOVxO1EDI=; b=PGgnnnmu744CGb0YyfGq+MKkiMsYkHFseWvMzBoypOerqtB64lppbv808X7FN6uXM9 6JWJPgCAdBsLlQdCX4gYIY6E9FLA5VrJ0cgHL3sR82pZKijEKj6Rp2RD4oWFtZ2+jUxd xiMsKQcNtbXoF/qh0lgE3WD7hebl+7YX9zKpwNJ6xQwLT2Ja20VZdJV7w0yeqXNGB6oB WigJdFhtd9Yqf8UqJwIjir7zYpVwIvCT/1gI1nzRvrz2jiKw17cvjZAGGc8ceAHFjl+9 87KuZe3QiRGc4+MePxjZvARNmg7tQVDSwA2LJYdJV6GXRb8EW4YMyMl2D0qLh+bIeMH2 Lekw== X-Gm-Message-State: AOJu0YxiZMgDTf7W8M+sLAXXBzhnLRJkmsMJiMo6zyOwS0HeUC17E0vG AAaCBWrxmIdQLvX4Ziva85g= X-Google-Smtp-Source: AGHT+IH7f9dMbrWKKHGtFn0wixUPmi92es8e9nKvgfoDM7cj2AaxpCAE29rN3hvCZNHSox3fFT7iuQ== X-Received: by 2002:a17:902:8301:b0:1d0:bcb2:4b8a with SMTP id bd1-20020a170902830100b001d0bcb24b8amr1553463plb.131.1702301410354; Mon, 11 Dec 2023 05:30:10 -0800 (PST) Received: from ?IPV6:2400:4050:a840:1e00:78d2:b862:10a7:d486? ([2400:4050:a840:1e00:78d2:b862:10a7:d486]) by smtp.gmail.com with ESMTPSA id p12-20020a170902e74c00b001d077da4ac4sm6543212plf.212.2023.12.11.05.30.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 11 Dec 2023 05:30:09 -0800 (PST) Message-ID: <44d8d424-33f4-4472-89f6-19b5fd2f359d@gmail.com> Date: Mon, 11 Dec 2023 22:30:06 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 4/5] qmp: Added new command to retrieve eBPF blob. Content-Language: en-US To: Andrew Melnychenko , jasowang@redhat.com, mst@redhat.com, armbru@redhat.com, eblake@redhat.com, qemu-devel@nongnu.org, berrange@redhat.com Cc: yuri.benditovich@daynix.com, yan@daynix.com References: <20230831065140.496485-1-andrew@daynix.com> <20230831065140.496485-5-andrew@daynix.com> From: Akihiko Odaki In-Reply-To: <20230831065140.496485-5-andrew@daynix.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::631; envelope-from=akihiko.odaki@gmail.com; helo=mail-pl1-x631.google.com X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_XBL=0.375, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no 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 On 2023/08/31 15:51, Andrew Melnychenko wrote: > 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 > --- > 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 0000000000..ea97c0403e > --- /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. > + */ Use SPDX License Identifier. I had been asked the same thing but unfortunately it's not documented in docs/devel/style.rst. > + > +#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; > +}; Add typedef. See docs/devel/style.rst. > + > +static QSLIST_HEAD(, ElfBinaryDataEntry) ebpf_elf_obj_list = > + QSLIST_HEAD_INITIALIZER(); Why don't you use GHashTable? > + > +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..b6266b28b8 > --- /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; Why do you need this? > + > +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 24bc6cc409..8679dc452d 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 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/qapi/ebpf.json b/qapi/ebpf.json > new file mode 100644 > index 0000000000..ba78407148 > --- /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 These need to be updated; we missed 8.2.