From patchwork Thu Jun 1 06:33:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Duan, Zhenzhong" X-Patchwork-Id: 13263085 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 7EECCC7EE23 for ; Thu, 1 Jun 2023 06:47:28 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q4c50-0004KQ-GR; Thu, 01 Jun 2023 02:46:38 -0400 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 1q4c4y-0004KI-2G for qemu-devel@nongnu.org; Thu, 01 Jun 2023 02:46:36 -0400 Received: from mga07.intel.com ([134.134.136.100]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q4c4w-00077p-74 for qemu-devel@nongnu.org; Thu, 01 Jun 2023 02:46:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685601993; x=1717137993; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=d1VixyNubrvQo5Vj6XTAaxOQt/YjrCUWfhpDJ8Iv61U=; b=kVV11IhlFINIvzSQjIquFm6rR8cNwF0szDBZTZXK9ZdruPvEnoY55lZD 4x27a4hq2AN0LwOO1n0ekB44fNIR8bEEunuHvuvrykUsHVMYkRo1jQ7cp GyGb1T91J0SpA8O87gLRxCc31KfRPO+JPqHiLiCHoXLdp5HFDP8kyiRY6 0COafhfVyWLVWKOaGajwSk7RUU5AXRU004ZIETJwBCZtxVZ6dOgWBa+WI q7kkMp/xE/oVjks1oFaNWnZh9aiF0lgYcPxmQ6gdjLb/UtX7UvrFJFfuP Cf2IpwMS/zLssmiA8/zIWs9DSWQ/ATk88IpigkLc97t/4t0TLRymeI6N+ w==; X-IronPort-AV: E=McAfee;i="6600,9927,10727"; a="421249381" X-IronPort-AV: E=Sophos;i="6.00,209,1681196400"; d="scan'208";a="421249381" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2023 23:46:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10727"; a="953953100" X-IronPort-AV: E=Sophos;i="6.00,209,1681196400"; d="scan'208";a="953953100" Received: from duan-server-s2600bt.bj.intel.com ([10.240.192.147]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2023 23:46:29 -0700 From: Zhenzhong Duan To: qemu-devel@nongnu.org Cc: mst@redhat.com, peterx@redhat.com, jasowang@redhat.com, pbonzini@redhat.com, richard.henderson@linaro.org, eduardo@habkost.net, marcel.apfelbaum@gmail.com, alex.williamson@redhat.com, clg@redhat.com, david@redhat.com, philmd@linaro.org, kwankhede@nvidia.com, cjia@nvidia.com, yi.l.liu@intel.com, chao.p.peng@intel.com Subject: [PATCH v2 4/4] intel_iommu: Optimize out some unnecessary UNMAP calls Date: Thu, 1 Jun 2023 14:33:20 +0800 Message-Id: <20230601063320.139308-5-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230601063320.139308-1-zhenzhong.duan@intel.com> References: <20230601063320.139308-1-zhenzhong.duan@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=134.134.136.100; envelope-from=zhenzhong.duan@intel.com; helo=mga07.intel.com X-Spam_score_int: -45 X-Spam_score: -4.6 X-Spam_bar: ---- X-Spam_report: (-4.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.163, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Commit 63b88968f1 ("intel-iommu: rework the page walk logic") adds IOVA tree to cache mapped ranges so we only need to send MAP or UNMAP when there are changes. But there is still a corner case of unnecessary UNMAP. During invalidation, either domain or device selective, we only need to unmap when there are recorded mapped IOVA ranges, presuming most of OSes allocating IOVA range continuously, e.g. on x86, linux sets up mapping from 0xffffffff downwards. Strace shows UNMAP ioctl taking 0.000014us and we have 28 such ioctl() in one invalidation, as two notifiers in x86 are split into power of 2 pieces. ioctl(48, VFIO_IOMMU_UNMAP_DMA, 0x7ffffd5c42f0) = 0 <0.000014> The other purpose of this patch is to eliminate noisy error log when we work with IOMMUFD. It looks the duplicate UNMAP call will fail with IOMMUFD while always succeed with legacy container. This behavior difference leads to below error log for IOMMUFD: IOMMU_IOAS_UNMAP failed: No such file or directory vfio_container_dma_unmap(0x562012d6b6d0, 0x0, 0x80000000) = -2 (No such file or directory) IOMMU_IOAS_UNMAP failed: No such file or directory vfio_container_dma_unmap(0x562012d6b6d0, 0x80000000, 0x40000000) = -2 (No such file or directory) ... Signed-off-by: Zhenzhong Duan --- hw/i386/intel_iommu.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 061fcded0dfb..a5fd144aa246 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -3743,6 +3743,7 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) hwaddr start = n->start; hwaddr end = n->end; IntelIOMMUState *s = as->iommu_state; + IOMMUTLBEvent event; DMAMap map; /* @@ -3762,22 +3763,25 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) assert(start <= end); size = remain = end - start + 1; + event.type = IOMMU_NOTIFIER_UNMAP; + event.entry.target_as = &address_space_memory; + event.entry.perm = IOMMU_NONE; + /* This field is meaningless for unmap */ + event.entry.translated_addr = 0; + while (remain >= VTD_PAGE_SIZE) { - IOMMUTLBEvent event; uint64_t mask = dma_aligned_pow2_mask(start, end, s->aw_bits); uint64_t size = mask + 1; assert(size); - event.type = IOMMU_NOTIFIER_UNMAP; - event.entry.iova = start; - event.entry.addr_mask = mask; - event.entry.target_as = &address_space_memory; - event.entry.perm = IOMMU_NONE; - /* This field is meaningless for unmap */ - event.entry.translated_addr = 0; - - memory_region_notify_iommu_one(n, &event); + map.iova = start; + map.size = mask; + if (iova_tree_find(as->iova_tree, &map)) { + event.entry.iova = start; + event.entry.addr_mask = mask; + memory_region_notify_iommu_one(n, &event); + } start += size; remain -= size; @@ -3791,7 +3795,7 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) n->start, size); map.iova = n->start; - map.size = size; + map.size = size - 1; /* Inclusive */ iova_tree_remove(as->iova_tree, map); }