From patchwork Tue Dec 19 15:15:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13498437 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 E9FB3C41535 for ; Tue, 19 Dec 2023 15:16:59 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rFbpU-0006O0-Ah; Tue, 19 Dec 2023 10:16:20 -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 1rFbpM-0006AE-9G for qemu-devel@nongnu.org; Tue, 19 Dec 2023 10:16:15 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rFbpH-0002B0-Hi for qemu-devel@nongnu.org; Tue, 19 Dec 2023 10:16:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1702998958; 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; bh=5xw7A1XKMUjdmB/9WndsfiguXhlbtnJE7+pJRM9nELs=; b=ewyXA1rHqDnQc7eW9eLVTn/xOMtxRostqDyxTMX6GSBpB/2YioJUD0VVpmIIFfyQdpKETp U/aRc+enc0WY27QTxWZHY5KVpKi+xw5pBCO4JQ/pZfw1a+gtbM9XCm9B52QPyF3cKanNtT TFTBmmAScJO7uP6Kxj4L8Q8AdhRkIJk= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-83-SAUPi0xiNaGf4qdi3wST1w-1; Tue, 19 Dec 2023 10:15:53 -0500 X-MC-Unique: SAUPi0xiNaGf4qdi3wST1w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (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 4481A29AA39A; Tue, 19 Dec 2023 15:15:53 +0000 (UTC) Received: from localhost (unknown [10.39.194.138]) by smtp.corp.redhat.com (Postfix) with ESMTP id B93271C060AF; Tue, 19 Dec 2023 15:15:52 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Michal Privoznik , Kevin Wolf , Stefan Hajnoczi , "Michael S. Tsirkin" , Michael Roth , Eduardo Habkost , Eric Blake , Paolo Bonzini , Markus Armbruster , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , qemu-block@nongnu.org, Hanna Reitz Subject: [PATCH v3 0/4] virtio-blk: add iothread-vq-mapping parameter Date: Tue, 19 Dec 2023 10:15:46 -0500 Message-ID: <20231219151550.223303-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.066, 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=unavailable 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 v3: - Rebased onto Kevin's block branch - Add StringOutputVisitor "" patch to fix "info qtree" crash - Fix QAPI schema formatting [Markus] - Eliminate unnecessary local variable in get_iothread_vq_mapping_list() [Markus] virtio-blk and virtio-scsi devices need a way to specify the mapping between IOThreads and virtqueues. At the moment all virtqueues are assigned to a single IOThread or the main loop. This single thread can be a CPU bottleneck, so it is necessary to allow finer-grained assignment to spread the load. With this series applied, "pidstat -t 1" shows that guests with -smp 2 or higher are able to exploit multiple IOThreads. This series introduces command-line syntax for the new iothread-vq-mapping property is as follows: --device '{"driver":"virtio-blk-pci","iothread-vq-mapping":[{"iothread":"iothread0","vqs":[0,1,2]},...]},...' IOThreads are specified by name and virtqueues are specified by 0-based index. It will be common to simply assign virtqueues round-robin across a set of IOThreads. A convenient syntax that does not require specifying individual virtqueue indices is available: --device '{"driver":"virtio-blk-pci","iothread-vq-mapping":[{"iothread":"iothread0"},{"iothread":"iothread1"},...]},...' There is no way to reassign virtqueues at runtime and I expect that to be a very rare requirement. Note that JSON --device syntax is required for the iothread-vq-mapping parameter because it's non-scalar. Based-on: 81e69329d6a4018f4b37d15b6fc845fbe585a93b (https://repo.or.cz/qemu/kevin.git block) Stefan Hajnoczi (4): qdev-properties: alias all object class properties string-output-visitor: show structs as "" qdev: add IOThreadVirtQueueMappingList property type virtio-blk: add iothread-vq-mapping parameter qapi/virtio.json | 30 ++++++ hw/block/dataplane/virtio-blk.h | 3 + include/hw/qdev-properties-system.h | 5 + include/hw/virtio/virtio-blk.h | 2 + include/qapi/string-output-visitor.h | 6 +- hw/block/dataplane/virtio-blk.c | 155 ++++++++++++++++++++------- hw/block/virtio-blk.c | 92 +++++++++++++--- hw/core/qdev-properties-system.c | 46 ++++++++ hw/core/qdev-properties.c | 18 ++-- qapi/string-output-visitor.c | 16 +++ 10 files changed, 312 insertions(+), 61 deletions(-)