From patchwork Wed Sep 13 20:00:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13383733 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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 18775EE020A for ; Wed, 13 Sep 2023 20:01:12 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.601544.937565 (Exim 4.92) (envelope-from ) id 1qgW2h-0006RW-5O; Wed, 13 Sep 2023 20:00:55 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 601544.937565; Wed, 13 Sep 2023 20:00:55 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qgW2h-0006RP-2s; Wed, 13 Sep 2023 20:00:55 +0000 Received: by outflank-mailman (input) for mailman id 601544; Wed, 13 Sep 2023 20:00:53 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qgW2f-0006RI-PN for xen-devel@lists.xenproject.org; Wed, 13 Sep 2023 20:00:53 +0000 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 3cd519d6-5270-11ee-9b0d-b553b5be7939; Wed, 13 Sep 2023 22:00:51 +0200 (CEST) Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-581-1gwriteAPry7x7A5OQM54w-1; Wed, 13 Sep 2023 16:00:48 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AC275805B29; Wed, 13 Sep 2023 20:00:47 +0000 (UTC) Received: from localhost (unknown [10.39.192.13]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2074A2156721; Wed, 13 Sep 2023 20:00:46 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 3cd519d6-5270-11ee-9b0d-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694635250; 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=nD7AyJZmmyRxiB9nG0IYAzAL7ZwFQ3Xa6S9su6nyaIc=; b=cH38GwRvBahH8OF9o5wQco8JAbqxLxIcHnrBH5np0/eue6GNmz5lHWCFHfIEyTsfkE3aQo NkTjSKJRjThQ3+4ueKSMKOWI6jSN9KIa0x3cYO2uHVT8XFsIegQN9PoLS1zaagzkdBdFLc uy14Lbk2n0KthbA2Z9m1nt18ics/gQk= X-MC-Unique: 1gwriteAPry7x7A5OQM54w-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Stefano Stabellini , Ilya Maximets , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Kevin Wolf , xen-devel@lists.xenproject.org, Anthony Perard , Paolo Bonzini , Stefan Hajnoczi , , Julia Suvorova , Aarushi Mehta , Paul Durrant , "Michael S. Tsirkin" , Fam Zheng , Stefano Garzarella , Hanna Reitz Subject: [PATCH v3 0/4] virtio-blk: use blk_io_plug_call() instead of notification BH Date: Wed, 13 Sep 2023 16:00:41 -0400 Message-ID: <20230913200045.1024233-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 v3: - Add comment pointing to API documentation in .c file [Philippe] - Add virtio_notify_irqfd_deferred_fn trace event [Ilya] - Remove outdated #include [Ilya] v2: - Rename blk_io_plug() to defer_call() and move it to util/ so the net subsystem can use it [Ilya] - Add defer_call_begin()/end() to thread_pool_completion_bh() to match Linux AIO and io_uring completion batching Replace the seldom-used virtio-blk notification BH mechanism with blk_io_plug(). This is part of an effort to enable the multi-queue block layer in virtio-blk. The notification BH was not multi-queue friendly. The blk_io_plug() mechanism improves fio rw=randread bs=4k iodepth=64 numjobs=8 IOPS by ~9% with a single IOThread and 8 vCPUs (this is not even a multi-queue block layer configuration) compared to no completion batching. iodepth=1 decreases by ~1% but this could be noise. Benchmark details are available here: https://gitlab.com/stefanha/virt-playbooks/-/tree/blk_io_plug-irqfd Stefan Hajnoczi (4): block: rename blk_io_plug_call() API to defer_call() util/defer-call: move defer_call() to util/ virtio: use defer_call() in virtio_irqfd_notify() virtio-blk: remove batch notification BH MAINTAINERS | 3 +- include/qemu/defer-call.h | 16 +++ include/sysemu/block-backend-io.h | 4 - block/blkio.c | 9 +- block/io_uring.c | 11 ++- block/linux-aio.c | 9 +- block/nvme.c | 5 +- block/plug.c | 159 ------------------------------ hw/block/dataplane/virtio-blk.c | 48 +-------- hw/block/dataplane/xen-block.c | 11 ++- hw/block/virtio-blk.c | 5 +- hw/scsi/virtio-scsi.c | 7 +- hw/virtio/virtio.c | 13 ++- util/defer-call.c | 156 +++++++++++++++++++++++++++++ util/thread-pool.c | 5 + block/meson.build | 1 - hw/virtio/trace-events | 1 + util/meson.build | 1 + 18 files changed, 231 insertions(+), 233 deletions(-) create mode 100644 include/qemu/defer-call.h delete mode 100644 block/plug.c create mode 100644 util/defer-call.c Reviewed-by: Michael S. Tsirkin