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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=ham 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 A7511C38A24 for ; Thu, 7 May 2020 16:41:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8102A20838 for ; Thu, 7 May 2020 16:41:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726807AbgEGQlB (ORCPT ); Thu, 7 May 2020 12:41:01 -0400 Received: from mga18.intel.com ([134.134.136.126]:21292 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726074AbgEGQlB (ORCPT ); Thu, 7 May 2020 12:41:01 -0400 IronPort-SDR: V+EVhH54npwUFooFSyBXESkwVRG1IV/ZUbtx9PuskHbq5ySbJf3W9vTlFNTzY0wYYsad+tWjz4 PiHm4gSFQPoA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 May 2020 09:41:00 -0700 IronPort-SDR: y/fdpHUpuRWavjaCIWw/VG9lnFOMSx4/mDNd/RiY3KqeeUtX9aU7JBbcyzHWw5kNUzNIfcmL29 7V3gnCOklWRA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,364,1583222400"; d="scan'208";a="407699732" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by orsmga004.jf.intel.com with ESMTP; 07 May 2020 09:40:59 -0700 Date: Thu, 7 May 2020 09:47:06 -0700 From: Jacob Pan To: Lu Baolu Cc: Joerg Roedel , ashok.raj@intel.com, Liu Yi L , kevin.tian@intel.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, jacob.jun.pan@linux.intel.com Subject: Re: [PATCH v4 2/5] iommu/vt-d: debugfs: Add support to show inv queue internals Message-ID: <20200507094706.6f6a605f@jacob-builder> In-Reply-To: <20200507005534.3080-3-baolu.lu@linux.intel.com> References: <20200507005534.3080-1-baolu.lu@linux.intel.com> <20200507005534.3080-3-baolu.lu@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Baolu, Very helpful feature, thanks for doing this. Just a small suggestion. On Thu, 7 May 2020 08:55:31 +0800 Lu Baolu wrote: > Export invalidation queue internals of each iommu device through the > debugfs. > > Example of such dump on a Skylake machine: > > $ sudo cat /sys/kernel/debug/iommu/intel/invalidation_queue > Invalidation queue on IOMMU: dmar1 > Base: 0x1672c9000 Head: 80 Tail: 80 > Index qw0 qw1 status > 0 0000000000000004 0000000000000000 > 0000000000000000 1 0000000200000025 00000001672be804 > 0000000000000000 2 0000000000000011 0000000000000000 > 0000000000000000 3 0000000200000025 00000001672be80c > 0000000000000000 4 00000000000000d2 0000000000000000 > 0000000000000000 5 0000000200000025 00000001672be814 > 0000000000000000 6 0000000000000014 0000000000000000 > 0000000000000000 7 0000000200000025 00000001672be81c > 0000000000000000 8 0000000000000014 0000000000000000 > 0000000000000000 9 0000000200000025 00000001672be824 > 0000000000000000 > Head and Tail shows the offset, and queue is dump with index. Would it be nice to mark where the Head and Tail is in the list? In your example, the queue is empty (H=T), would be nice to see where the previous entry is if there were any faults. > Signed-off-by: Lu Baolu > --- > drivers/iommu/intel-iommu-debugfs.c | 62 > +++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) > > diff --git a/drivers/iommu/intel-iommu-debugfs.c > b/drivers/iommu/intel-iommu-debugfs.c index > 3eb1fe240fb0..e3089865b8f3 100644 --- > a/drivers/iommu/intel-iommu-debugfs.c +++ > b/drivers/iommu/intel-iommu-debugfs.c @@ -372,6 +372,66 @@ static int > domain_translation_struct_show(struct seq_file *m, void *unused) } > DEFINE_SHOW_ATTRIBUTE(domain_translation_struct); > > +static void invalidation_queue_entry_show(struct seq_file *m, > + struct intel_iommu *iommu) > +{ > + int index, shift = qi_shift(iommu); > + struct qi_desc *desc; > + int offset; > + > + if (ecap_smts(iommu->ecap)) > + seq_puts(m, > "Index\t\tqw0\t\t\tqw1\t\t\tqw2\t\t\tqw3\t\t\tstatus\n"); > + else > + seq_puts(m, "Index\t\tqw0\t\t\tqw1\t\t\tstatus\n"); > + > + for (index = 0; index < QI_LENGTH; index++) { > + offset = index << shift; > + desc = iommu->qi->desc + offset; > + if (ecap_smts(iommu->ecap)) > + seq_printf(m, > "%5d\t%016llx\t%016llx\t%016llx\t%016llx\t%016x\n", > + index, desc->qw0, desc->qw1, > + desc->qw2, desc->qw3, > + iommu->qi->desc_status[index]); > + else > + seq_printf(m, > "%5d\t%016llx\t%016llx\t%016x\n", > + index, desc->qw0, desc->qw1, > + iommu->qi->desc_status[index]); > + } > +} > + > +static int invalidation_queue_show(struct seq_file *m, void *unused) > +{ > + struct dmar_drhd_unit *drhd; > + struct intel_iommu *iommu; > + unsigned long flags; > + struct q_inval *qi; > + int shift; > + > + rcu_read_lock(); > + for_each_active_iommu(iommu, drhd) { > + qi = iommu->qi; > + shift = qi_shift(iommu); > + > + if (!qi || !ecap_qis(iommu->ecap)) > + continue; > + > + seq_printf(m, "Invalidation queue on IOMMU: %s\n", > iommu->name); + > + raw_spin_lock_irqsave(&qi->q_lock, flags); > + seq_printf(m, " Base: 0x%llx\tHead: %lld\tTail: > %lld\n", > + virt_to_phys(qi->desc), > + dmar_readq(iommu->reg + DMAR_IQH_REG) >> > shift, > + dmar_readq(iommu->reg + DMAR_IQT_REG) >> > shift); > + invalidation_queue_entry_show(m, iommu); > + raw_spin_unlock_irqrestore(&qi->q_lock, flags); > + seq_putc(m, '\n'); > + } > + rcu_read_unlock(); > + > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(invalidation_queue); > + > #ifdef CONFIG_IRQ_REMAP > static void ir_tbl_remap_entry_show(struct seq_file *m, > struct intel_iommu *iommu) > @@ -490,6 +550,8 @@ void __init intel_iommu_debugfs_init(void) > debugfs_create_file("domain_translation_struct", 0444, > intel_iommu_debug, NULL, > &domain_translation_struct_fops); > + debugfs_create_file("invalidation_queue", 0444, > intel_iommu_debug, > + NULL, &invalidation_queue_fops); > #ifdef CONFIG_IRQ_REMAP > debugfs_create_file("ir_translation_struct", 0444, > intel_iommu_debug, NULL, &ir_translation_struct_fops); [Jacob Pan]