From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04D7BC433FF for ; Mon, 12 Aug 2019 08:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CDE052070C for ; Mon, 12 Aug 2019 08:52:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727241AbfHLIwU (ORCPT ); Mon, 12 Aug 2019 04:52:20 -0400 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:48127 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbfHLIwU (ORCPT ); Mon, 12 Aug 2019 04:52:20 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04391;MF=luoben@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0TZGPiR-_1565599926; Received: from localhost(mailfrom:luoben@linux.alibaba.com fp:SMTPD_---0TZGPiR-_1565599926) by smtp.aliyun-inc.com(127.0.0.1); Mon, 12 Aug 2019 16:52:14 +0800 From: Ben Luo To: tglx@linutronix.de, alex.williamson@redhat.com, linux-kernel@vger.kernel.org Cc: tao.ma@linux.alibaba.com, gerry@linux.alibaba.com, nanhai.zou@linux.alibaba.com, linyunsheng@huawei.com Subject: [PATCH v2 0/3] introduce update_irq_devid and optimize VFIO irq ops Date: Mon, 12 Aug 2019 16:52:03 +0800 Message-Id: X-Mailer: git-send-email 1.8.3.1 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, VFIO takes a lot of free-then-request-irq actions whenever a VM (with device passthru via VFIO) sets irq affinity or mask/unmask irq. Those actions only change the cookie data of irqaction or even change nothing. The free-then-request-irq not only add more latency, but also increases the risk of losing interrupt, this may lead to a VM hung forever in waiting IO completion This patchset solved this issue by: Patch 2 introduces update_irq_devid to only update dev_id of irqaction Patch 3 make use of update_irq_devid and optimize irq operations in VFIO changes from v1: - add Patch 1 to enhance error recovery etc. in free irq per tglx's comments - enhance error recovery code and debugging info in update_irq_devid - use __must_check in external referencing of update_irq_devid - use EXPORT_SYMBOL_GPL for update_irq_devid - reformat code of patch 3 for better readability Ben Luo (3): genirq: enhance error recovery code in free irq genirq: introduce update_irq_devid() vfio_pci: make use of update_irq_devid and optimize irq ops drivers/vfio/pci/vfio_pci_intrs.c | 99 +++++++++++++++++++++------------- include/linux/interrupt.h | 3 ++ kernel/irq/manage.c | 111 +++++++++++++++++++++++++++++++++----- 3 files changed, 163 insertions(+), 50 deletions(-) -- 1.8.3.1