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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6099C433EF for ; Wed, 29 Sep 2021 07:35:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6020861406 for ; Wed, 29 Sep 2021 07:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244620AbhI2Hgk (ORCPT ); Wed, 29 Sep 2021 03:36:40 -0400 Received: from mga18.intel.com ([134.134.136.126]:47668 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243249AbhI2Hgi (ORCPT ); Wed, 29 Sep 2021 03:36:38 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10121"; a="211965594" X-IronPort-AV: E=Sophos;i="5.85,331,1624345200"; d="scan'208";a="211965594" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2021 00:34:58 -0700 X-IronPort-AV: E=Sophos;i="5.85,331,1624345200"; d="scan'208";a="563039522" Received: from blu2-mobl3.ccr.corp.intel.com (HELO [10.254.210.53]) ([10.254.210.53]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2021 00:34:53 -0700 Cc: baolu.lu@linux.intel.com, iommu@lists.linux-foundation.org, x86 , linux-kernel Subject: Re: [PATCH 1/8] iommu/vt-d: Clean up unused PASID updating functions To: Fenghua Yu , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Peter Zijlstra , Andy Lutomirski , Dave Hansen , Tony Luck , Joerg Roedel , Josh Poimboeuf , Dave Jiang , Jacob Jun Pan , Ashok Raj , Ravi V Shankar References: <20210920192349.2602141-1-fenghua.yu@intel.com> <20210920192349.2602141-2-fenghua.yu@intel.com> From: Lu Baolu Message-ID: <2f2ab378-9967-ff84-18f1-c48ddeb0ceb6@linux.intel.com> Date: Wed, 29 Sep 2021 15:34:51 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <20210920192349.2602141-2-fenghua.yu@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Fenghua, On 2021/9/21 3:23, Fenghua Yu wrote: > update_pasid() and its call chain are currently unused in the tree because > Thomas disabled the ENQCMD feature. The feature will be re-enabled shortly > using a different approach and update_pasid() and its call chain will not > be used in the new approach. > > Remove the useless functions. > > Signed-off-by: Fenghua Yu > Reviewed-by: Tony Luck Thanks for this cleanup. I have queued it for v5.16. Best regards, baolu > --- > arch/x86/include/asm/fpu/api.h | 2 -- > drivers/iommu/intel/svm.c | 24 +----------------------- > 2 files changed, 1 insertion(+), 25 deletions(-) > > diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h > index 23bef08a8388..ca4d0dee1ecd 100644 > --- a/arch/x86/include/asm/fpu/api.h > +++ b/arch/x86/include/asm/fpu/api.h > @@ -106,6 +106,4 @@ extern int cpu_has_xfeatures(u64 xfeatures_mask, const char **feature_name); > */ > #define PASID_DISABLED 0 > > -static inline void update_pasid(void) { } > - > #endif /* _ASM_X86_FPU_API_H */ > diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c > index 0c228787704f..5b5d69b04fcc 100644 > --- a/drivers/iommu/intel/svm.c > +++ b/drivers/iommu/intel/svm.c > @@ -505,21 +505,6 @@ int intel_svm_unbind_gpasid(struct device *dev, u32 pasid) > return ret; > } > > -static void _load_pasid(void *unused) > -{ > - update_pasid(); > -} > - > -static void load_pasid(struct mm_struct *mm, u32 pasid) > -{ > - mutex_lock(&mm->context.lock); > - > - /* Update PASID MSR on all CPUs running the mm's tasks. */ > - on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true); > - > - mutex_unlock(&mm->context.lock); > -} > - > static int intel_svm_alloc_pasid(struct device *dev, struct mm_struct *mm, > unsigned int flags) > { > @@ -614,10 +599,6 @@ static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu, > if (ret) > goto free_sdev; > > - /* The newly allocated pasid is loaded to the mm. */ > - if (!(flags & SVM_FLAG_SUPERVISOR_MODE) && list_empty(&svm->devs)) > - load_pasid(mm, svm->pasid); > - > list_add_rcu(&sdev->list, &svm->devs); > success: > return &sdev->sva; > @@ -670,11 +651,8 @@ static int intel_svm_unbind_mm(struct device *dev, u32 pasid) > kfree_rcu(sdev, rcu); > > if (list_empty(&svm->devs)) { > - if (svm->notifier.ops) { > + if (svm->notifier.ops) > mmu_notifier_unregister(&svm->notifier, mm); > - /* Clear mm's pasid. */ > - load_pasid(mm, PASID_DISABLED); > - } > pasid_private_remove(svm->pasid); > /* We mandate that no page faults may be outstanding > * for the PASID when intel_svm_unbind_mm() is called. >