From patchwork Wed Nov 3 08:16:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Longpeng(Mike)" X-Patchwork-Id: 12600337 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 79A09C4332F for ; Wed, 3 Nov 2021 08:17:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F0B660F90 for ; Wed, 3 Nov 2021 08:17:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231702AbhKCITs (ORCPT ); Wed, 3 Nov 2021 04:19:48 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:14708 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230025AbhKCITp (ORCPT ); Wed, 3 Nov 2021 04:19:45 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4HkfhP4RvMzW259; Wed, 3 Nov 2021 16:15:01 +0800 (CST) Received: from dggpeml100016.china.huawei.com (7.185.36.216) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Wed, 3 Nov 2021 16:17:06 +0800 Received: from DESKTOP-27KDQMV.china.huawei.com (10.174.148.223) by dggpeml100016.china.huawei.com (7.185.36.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Wed, 3 Nov 2021 16:17:06 +0800 From: "Longpeng(Mike)" To: , CC: , , , "Longpeng(Mike)" Subject: [PATCH v5 0/6] optimize the downtime for vfio migration Date: Wed, 3 Nov 2021 16:16:51 +0800 Message-ID: <20211103081657.1945-1-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 MIME-Version: 1.0 X-Originating-IP: [10.174.148.223] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpeml100016.china.huawei.com (7.185.36.216) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi guys, In vfio migration resume phase, the cost would increase if the vfio device has more unmasked vectors. We try to optimize it in this series. You can see the commit message in PATCH 6 for details. Patch 1-3 are simple cleanups and fixup. Patch 4-5 are the preparations for the optimization. Patch 6 optimizes the vfio msix setup path. Changes v4->v5: - setup the notifier and irqfd in the same function to makes the code neater. [Alex] Changes v3->v4: - fix several typos and grammatical errors [Alex] - remove the patches that fix and clean the MSIX common part from this series [Alex] - Patch 6: - use vector->use directly and fill it with -1 on error paths [Alex] - add comment before enable deferring to commit [Alex] - move the code that do_use/release on vector 0 into an "else" branch [Alex] - introduce vfio_prepare_kvm_msi_virq_batch() that enables the 'defer_kvm_irq_routing' flag [Alex] - introduce vfio_commit_kvm_msi_virq_batch() that clears the 'defer_kvm_irq_routing' flag and does further work [Alex] Changes v2->v3: - fix two errors [Longpeng] Changes v1->v2: - fix several typos and grammatical errors [Alex, Philippe] - split fixups and cleanups into separate patches [Alex, Philippe] - introduce kvm_irqchip_add_deferred_msi_route to minimize code changes [Alex] - enable the optimization in msi setup path [Alex] Longpeng (Mike) (6): vfio: simplify the conditional statements in vfio_msi_enable vfio: move re-enabling INTX out of the common helper vfio: simplify the failure path in vfio_msi_enable kvm: irqchip: extract kvm_irqchip_add_deferred_msi_route Revert "vfio: Avoid disabling and enabling vectors repeatedly in VFIO migration" vfio: defer to commit kvm irq routing when enable msi/msix accel/kvm/kvm-all.c | 15 ++++- hw/vfio/pci.c | 176 ++++++++++++++++++++++++++++++++------------------- hw/vfio/pci.h | 1 + include/sysemu/kvm.h | 6 ++ 4 files changed, 130 insertions(+), 68 deletions(-)