From patchwork Tue Mar 11 10:11:32 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 14011452 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 B0434C282EC for ; Tue, 11 Mar 2025 10:16:44 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1trwai-0006Iz-RJ; Tue, 11 Mar 2025 06:12:04 -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 1trwah-0006Ib-8b for qemu-devel@nongnu.org; Tue, 11 Mar 2025 06:12:03 -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 1trwac-0005bc-Iq for qemu-devel@nongnu.org; Tue, 11 Mar 2025 06:12:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741687916; 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=dcOmmX2L1DEmKgX+XZoA+6XRrAywzxnBS2dxh9QUWoA=; b=L3fTAouKUEXB1HEnioECWcSZMPfcSXk0crt1+yAai36Tjp+VZW9pXEdXKlxskK0N9FWOMT DJTFZ445o4EL66aLt23LDx422nRx6UitJ1VzywgnrYlFFcRY7qwJVUABNPIm+jl0ma4vnx KSQBLrBOvrFN7WwJC6PjOijmJIpJDqw= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-310-8uj2nQcCPIuGfnbvRnvJsw-1; Tue, 11 Mar 2025 06:11:53 -0400 X-MC-Unique: 8uj2nQcCPIuGfnbvRnvJsw-1 X-Mimecast-MFC-AGG-ID: 8uj2nQcCPIuGfnbvRnvJsw_1741687912 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-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id F371619560B4; Tue, 11 Mar 2025 10:11:49 +0000 (UTC) Received: from localhost (unknown [10.2.16.75]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 4453819560AD; Tue, 11 Mar 2025 10:11:47 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Paolo Bonzini , David Hildenbrand , , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Peter Xu , Kevin Wolf , Fam Zheng , "Michael S. Tsirkin" , Stefan Hajnoczi , Hanna Reitz , pkrempa@redhat.com, John Snow Subject: [PATCH v2 00/13] virtio-scsi: add iothread-vq-mapping parameter Date: Tue, 11 Mar 2025 18:11:32 +0800 Message-ID: <20250311101145.1037388-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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_H2=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_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 v2: - Only expose cmd vqs via iothread-vq-mapping [Kevin, Peter] 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. virtio-scsi: only expose cmd vqs via iothread-vq-mapping Make the user interface more intuitive. Stefan Hajnoczi (13): 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 virtio-scsi: only expose cmd vqs via iothread-vq-mapping 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 | 103 +++-- hw/scsi/virtio-scsi.c | 542 ++++++++++++++---------- hw/virtio/iothread-vq-mapping.c | 131 ++++++ system/dma-helpers.c | 8 +- hw/virtio/meson.build | 1 + 14 files changed, 683 insertions(+), 456 deletions(-) create mode 100644 include/hw/virtio/iothread-vq-mapping.h create mode 100644 hw/virtio/iothread-vq-mapping.c