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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 63546C83002 for ; Tue, 28 Apr 2020 01:47:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35FED2070B for ; Tue, 28 Apr 2020 01:47:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726348AbgD1BrM (ORCPT ); Mon, 27 Apr 2020 21:47:12 -0400 Received: from mga06.intel.com ([134.134.136.31]:30711 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726264AbgD1BrM (ORCPT ); Mon, 27 Apr 2020 21:47:12 -0400 IronPort-SDR: 3k1w4RYi2o+1b8HmbTiH1yXkJvKfpKCGr7Fxwl8qR+kejPu/MDbxkhWs5enP7qr58Y8U5x4f6n QM1+0AWaijig== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Apr 2020 18:47:11 -0700 IronPort-SDR: HHrSf2zNwP3Z3RdFg6IPqorcVVnRcv8CQUZlxIpElwsFxEhIW4hgKIVeSHPlUpIKgKgfaU1bzD H6EaVfMXZcxA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,325,1583222400"; d="scan'208";a="367345195" Received: from blu2-mobl3.ccr.corp.intel.com (HELO [10.254.212.128]) ([10.254.212.128]) by fmsmga001.fm.intel.com with ESMTP; 27 Apr 2020 18:47:09 -0700 Cc: Joerg Roedel , baolu.lu@linux.intel.com, ashok.raj@intel.com, jacob.jun.pan@linux.intel.com, Liu Yi L , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/4] iommu/vt-d: Add page request draining support To: kevin.tian@intel.com References: <20200422080611.15689-1-baolu.lu@linux.intel.com> From: Lu Baolu Message-ID: <714e0552-ae31-fa4a-76fe-d3c38e064e0a@linux.intel.com> Date: Tue, 28 Apr 2020 09:47:08 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200422080611.15689-1-baolu.lu@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kevin, On 2020/4/22 16:06, Lu Baolu wrote: > When a PASID is stopped or terminated, there can be pending PRQs > (requests that haven't received responses) in the software and > remapping hardware. The pending page requests must be drained > so that the pasid could be reused. The chapter 7.10 in the VT-d > specification specifies the software steps to drain pending page > requests and responses. > > This includes two parts: > - PATCH 1/4 ~ 2/4: refactor the qi_submit_sync() to support multiple > descriptors per submission which will be used in the following > patch. > - PATCH 3/4 ~ 4/4: add page request drain support after a pasid entry > is torn down. > > Please help to review. > > Best regards, > baolu > > Change log: > v2->v3: > - Address Kevin's review comments > - Squash the first 2 patches together; > - The prq thread is serialized, no need to consider reentrance; > - Ensure no new-coming prq before drain prq in queue; > - Handle page request overflow case. Very appreciated for your review comments. How about these changes? Any comments? Best regards, baolu