From patchwork Thu Feb 13 18:00:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13973818 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 F2711C021A6 for ; Thu, 13 Feb 2025 18:03:04 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tidWZ-0007rJ-OS; Thu, 13 Feb 2025 13:01:21 -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 1tidWE-0007fw-To for qemu-devel@nongnu.org; Thu, 13 Feb 2025 13:00:59 -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 1tidWC-0006Pf-V4 for qemu-devel@nongnu.org; Thu, 13 Feb 2025 13:00:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1739469653; 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=7bpxq8mz8Sv+m+s38czM6zURIi0j+FKNnxHbgG6JYKU=; b=RIQXt2cIW+QiddqI5nmM4WpbgHcFoTRn1prE7NS/N3AxgU6hymdXHs1K3tcOpZjlr0SCEu 7thBQAt33bclr1Wta8oVu5hOJ5NpLShUJzrnEX0ikzbCWEf9cshJ8N7F1PJrSJXANgTo0C /nInwdb72C4A5mVxRo1nSRLCRVqVrkc= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-435-UpybSlBeN0qtdZN6tJzgvQ-1; Thu, 13 Feb 2025 13:00:49 -0500 X-MC-Unique: UpybSlBeN0qtdZN6tJzgvQ-1 X-Mimecast-MFC-AGG-ID: UpybSlBeN0qtdZN6tJzgvQ Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (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 mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2B0D01800878; Thu, 13 Feb 2025 18:00:47 +0000 (UTC) Received: from localhost (unknown [10.2.16.157]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 69E721955DCE; Thu, 13 Feb 2025 18:00:45 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Paolo Bonzini , John Snow , Fam Zheng , Peter Xu , =?utf-8?q?Philipp?= =?utf-8?q?e_Mathieu-Daud=C3=A9?= , "Michael S. Tsirkin" , qemu-block@nongnu.org, Stefan Hajnoczi , Kevin Wolf , David Hildenbrand , pkrempa@redhat.com, Hanna Reitz Subject: [PATCH 00/12] virtio-scsi: add iothread-vq-mapping parameter Date: Thu, 13 Feb 2025 13:00:31 -0500 Message-ID: <20250213180043.713434-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 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: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.495, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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 Implement --device virtio-scsi-pci,iothread-vq-mapping= support so that virtqueues can be assigned to different IOThreads. This improves SMP guest scalability where I/O-intensive applications can become bottlenecked on a single IOThread. The following benchmark results show the effect of iothread-vq-mapping. fio randread 4k iodepth=64 results from a 4 vCPU guest with an Intel P4800X SSD: iothreads IOPS ------------------------------ 1 189576 2 312698 4 346744 The virtio-scsi device model and core SCSI emulation currently assume that requests are processed in a single AioContext. This patch series goes about modifying this as follows: scsi-disk: drop unused SCSIDiskState->bh field dma: use current AioContext for dma_blk_io() Make dma-helpers.c support the QEMU multi-queue block layer by using qemu_get_current_aio_context(). scsi: track per-SCSIRequest AioContext scsi: introduce requests_lock Make the core SCSI emulation code support processing requests in multiple AioContexts by protecting the per-SCSIDevice requests list. virtio-scsi: introduce event and ctrl virtqueue locks virtio-scsi: protect events_dropped field virtio-scsi: perform TMFs in appropriate AioContexts Make the virtio-scsi emulation code support processing requests in multiple AioContexts. The event and ctrl virtqueues can interact with multiple AioContexts. Especially the SCSI Task Management Functions (TMFs) handled by the ctrl virtqueue need to be made thread-safe. virtio-blk: extract cleanup_iothread_vq_mapping() function virtio-blk: tidy up iothread_vq_mapping functions virtio: extract iothread-vq-mapping.h API virtio-scsi: add iothread-vq-mapping parameter Port over the iothread-vq-mapping qdev property from virtio-blk to virtio-scsi. virtio-scsi: handle ctrl virtqueue in main loop Simplify TMF handling now that there is no longer a single AioContext where all requests are processed. Stefan Hajnoczi (12): scsi-disk: drop unused SCSIDiskState->bh field dma: use current AioContext for dma_blk_io() scsi: track per-SCSIRequest AioContext scsi: introduce requests_lock virtio-scsi: introduce event and ctrl virtqueue locks virtio-scsi: protect events_dropped field virtio-scsi: perform TMFs in appropriate AioContexts virtio-blk: extract cleanup_iothread_vq_mapping() function virtio-blk: tidy up iothread_vq_mapping functions virtio: extract iothread-vq-mapping.h API virtio-scsi: add iothread-vq-mapping parameter virtio-scsi: handle ctrl virtqueue in main loop include/hw/scsi/scsi.h | 8 +- include/hw/virtio/iothread-vq-mapping.h | 45 ++ include/hw/virtio/virtio-scsi.h | 15 +- include/system/dma.h | 3 +- hw/block/virtio-blk.c | 132 +----- hw/ide/core.c | 3 +- hw/ide/macio.c | 3 +- hw/scsi/scsi-bus.c | 121 ++++-- hw/scsi/scsi-disk.c | 24 +- hw/scsi/virtio-scsi-dataplane.c | 96 +++-- hw/scsi/virtio-scsi.c | 534 ++++++++++++++---------- hw/virtio/iothread-vq-mapping.c | 131 ++++++ system/dma-helpers.c | 8 +- hw/virtio/meson.build | 1 + 14 files changed, 672 insertions(+), 452 deletions(-) create mode 100644 include/hw/virtio/iothread-vq-mapping.h create mode 100644 hw/virtio/iothread-vq-mapping.c Tested-by: Peter Krempa