From patchwork Tue Dec 6 08:18:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhijian Li (Fujitsu)\" via" X-Patchwork-Id: 13065508 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 E7A5AC352A1 for ; Tue, 6 Dec 2022 08:19:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p2TAs-0007UO-NK; Tue, 06 Dec 2022 03:19:34 -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 1p2TAj-0007OT-Ef for qemu-devel@nongnu.org; Tue, 06 Dec 2022 03:19:27 -0500 Received: from szxga01-in.huawei.com ([45.249.212.187]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2TAg-0005Ds-LZ for qemu-devel@nongnu.org; Tue, 06 Dec 2022 03:19:25 -0500 Received: from kwepemi100025.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NRCwh39NKzmWQF; Tue, 6 Dec 2022 16:18:28 +0800 (CST) Received: from DESKTOP-27KDQMV.china.huawei.com (10.174.148.223) by kwepemi100025.china.huawei.com (7.221.188.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 6 Dec 2022 16:18:45 +0800 To: , , , CC: , , , , , , Longpeng Subject: [PATCH v2 2/2] vdpa: commit all host notifier MRs in a single MR transaction Date: Tue, 6 Dec 2022 16:18:41 +0800 Message-ID: <20221206081841.2458-3-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 In-Reply-To: <20221206081841.2458-1-longpeng2@huawei.com> References: <20221206081841.2458-1-longpeng2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.148.223] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemi100025.china.huawei.com (7.221.188.158) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.187; envelope-from=longpeng2@huawei.com; helo=szxga01-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: , Reply-to: "Longpeng(Mike)" X-Patchwork-Original-From: "Longpeng(Mike)" via From: "Zhijian Li (Fujitsu)\" via" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Longpeng This allows the vhost-vdpa device to batch the setup of all its MRs of host notifiers. This significantly reduces the device starting time, e.g. the time spend on setup the host notifier MRs reduce from 423ms to 32ms for a VM with 64 vCPUs and 3 vhost-vDPA generic devices[1] (64vq per device). [1] https://www.mail-archive.com/qemu-devel@nongnu.org/msg921541.html Signed-off-by: Longpeng --- hw/virtio/vhost-vdpa.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index 7468e44b87..eb233cf08a 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -547,9 +547,18 @@ static void vhost_vdpa_host_notifiers_uninit(struct vhost_dev *dev, int n) { int i; + /* + * Pack all the changes to the memory regions in a single + * transaction to avoid a few updating of the address space + * topology. + */ + memory_region_transaction_begin(); + for (i = dev->vq_index; i < dev->vq_index + n; i++) { vhost_vdpa_host_notifier_uninit(dev, i); } + + memory_region_transaction_commit(); } static void vhost_vdpa_host_notifiers_init(struct vhost_dev *dev) @@ -562,16 +571,25 @@ static void vhost_vdpa_host_notifiers_init(struct vhost_dev *dev) return; } + /* + * Pack all the changes to the memory regions in a single + * transaction to avoid a few updating of the address space + * topology. + */ + memory_region_transaction_begin(); + for (i = dev->vq_index; i < dev->vq_index + dev->nvqs; i++) { if (vhost_vdpa_host_notifier_init(dev, i)) { goto err; } } + memory_region_transaction_commit(); return; err: vhost_vdpa_host_notifiers_uninit(dev, i - dev->vq_index); + memory_region_transaction_commit(); return; }