Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <3edf5f82-bc4a-9fda-93c2-a2d4b4b8e973@intel.com>
Date:   Tue, 1 Aug 2023 14:30:23 +0300
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.13.0
Subject: Re: [PATCH v4 10/29] drm/i915/gvt: Drop unused helper
 intel_vgpu_reset_gtt()
Content-Language: en-US
To:     Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Zhenyu Wang <zhenyuw@linux.intel.com>
CC:     <kvm@vger.kernel.org>, <intel-gvt-dev@lists.freedesktop.org>,
        <intel-gfx@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>,
        Yan Zhao <yan.y.zhao@intel.com>,
        Yongwei Ma <yongwei.ma@intel.com>,
        Ben Gardon <bgardon@google.com>
References: <20230729013535.1070024-1-seanjc@google.com>
 <20230729013535.1070024-11-seanjc@google.com>
From:   "Wang, Zhi A" <zhi.a.wang@intel.com>
In-Reply-To: <20230729013535.1070024-11-seanjc@google.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?SjBRdlZJa2hhaGExNnplQlZRNEN3WHFEY1J6UGV0LzM4Rlo1cXZKVnNlV2hj?=
 =?utf-8?B?SHl1cnNWWU0yVzV4N2hWQ1luRE94NDFZM0VVOXhBckpvRVhyVWNpR3JTd1R3?=
 =?utf-8?B?NkNYKzdjTTQ1dldQYjVzRnRrb2NZMTZKazFpWXp6cHJBV3hFTHpHWEx1NFJ1?=
 =?utf-8?B?RlNHUHh3RHkwbno5YnJEdWhIeXZWZkNqcjVoR2JickFBa0FhWUIwbXBQU29z?=
 =?utf-8?B?K0E2UVJ6QXdTSVphSFlKVlI3dWtSd1kraGNvNzZqQnprekRQa0svcEZhVkxV?=
 =?utf-8?B?R2VtMWJ4cXo4KzZsZVp6OXo0NXlBdjFqQjNEUE9aWHVreXZ0dE5FOUw2WDZt?=
 =?utf-8?B?NUJDU0E1NW8yR2dNaS9ZbkNkeVdYMjQzYkRMdWFyRzR6SlNsRm04VWpuRG8x?=
 =?utf-8?B?YTB4MkczelJlTzMxWmxYNnpuc3J5cGhjUUJUMXFRZDIxWGszK0p0THo2NFNk?=
 =?utf-8?B?Tng4cUFMRjB5dWp5Kys5NjJkcTNON1J0akRVdzk5Q0EwR0FsSFpTZC9nWWVr?=
 =?utf-8?B?dDJxN29QOEh6MFNpME02ZW9tTTFOTkZGZTBEM3lNOXVZS0lhOWZueGRDWk1H?=
 =?utf-8?B?YzBYN0dpMHBmTVVqcVpsNGVGaTFHMkRxc2hHdWdrK0g1SnBuUUZFVkgyN2Ni?=
 =?utf-8?B?aldOZ2V1SGJXeGxOTDBSNUxqL1VtaWVNT1lucWFUOFdxVFdUdUFIQUpnY0ZX?=
 =?utf-8?B?ZGpKNnFkYVFyam9xYzFtSnY2MUlyZmNqdkwyNDhjTHRSbjVIZXZFeVMyWnh2?=
 =?utf-8?B?bUdtTzd6SzhFQlJDbFl2Z1I1Tm85QWx1dmczei9jNUQwQlVnZU9MYTh1NUNP?=
 =?utf-8?B?NUVCakVDamlmYTNXK2tNWXVkU1EydXVWNWpvZXRqSDNmNng4YW5UaUdja1do?=
 =?utf-8?B?NW9HUDBzL21hZWlpcW1ZMWtLdkFEdkhNNkl1Nlk2U1M3b3FESmk5Qy9venM4?=
 =?utf-8?B?UllBbDhIL0xkZE8waU5LS1Ntd05kZ3ozQ0NDQVg3SlRBOXVYL3ZpbjFXaVNi?=
 =?utf-8?B?Vjh0RTdaSm9uTmFLalVxRENVMlFJWUZydWxPdGk5Y0FTT082RmpnM3dQZ1R5?=
 =?utf-8?B?M09CNFFLZjgwazAzb28vMTh2elplbGtCWkhNdjNEbHZqaDlMN0NIVmRGRVV3?=
 =?utf-8?B?c01yaWZCM0FIZ0tGUysxNDY3clJwdEdiaDQrQVg2UW15eDVhTnBSUGxuUFRM?=
 =?utf-8?B?QWZiNDVobnVGU3BWcFRQc1pOS1NhbWU5ZFVYOG9mSjBKN2htNWxNSWdlL3Iy?=
 =?utf-8?B?eHJxYllNSUVtWDRzS1pIcUFrSE55NjlDMW11M0VVaktWbUQvOEVKcjJIdlln?=
 =?utf-8?B?a1hzMlZ4NGZiaDVIdktCTndzZDdKbzQ3ZW1aeGRoRDZQS1lnTGVYeEI1M25Z?=
 =?utf-8?B?OG1VdGtLeFBJUmRCMHk0UmhlN1lPdzhOc3RXUjltME5xRXFVSWdQbnVRT24z?=
 =?utf-8?B?RHJMQnFDUEQxZ3BkelZoVUEwMHRVWDlTRWxZdldoOVMvSHUrOEpMWkluTCtZ?=
 =?utf-8?B?cVFGRHZRS2lOOVo0UWdnUERFZG13QVJlcktKeDNCVHRCSkF0SEpXY1BkQ2NC?=
 =?utf-8?B?YVIyVVoyWGYxZ0ErVndKcm1CM1NwWjd1YkUrc0txdTNPRDVXNGNLcDNoNlhu?=
 =?utf-8?B?SFJvMnVHSW1yOHNEc0pVZVNoWklWYTNvallUbjR1SERUemE1VjRwZllZL3Br?=
 =?utf-8?B?NkY1OFNvbzFVQkRHcmNWb3YwRVFTSHFaK0d1aXFMYzZ1UjVXUkNDQnRDanZx?=
 =?utf-8?B?cWt2a1FFVkpDNFdQeGkrTXVHdUsvdUQ0bW83WWNhZG1IVFh1NWwvT2VjaUZD?=
 =?utf-8?B?WHMrT0FJekxXOStXQUFFZ1VkSmN4QkJyK3J3QUpBZlV5RHNZb2xVa2JHcVVC?=
 =?utf-8?B?MHBtMXRsb3pOVElVN0NidmN3bGRJb1pZc2NKRkJkSXdtakEvVkF3aWRQVVQv?=
 =?utf-8?B?YlgyQ3RHMjVwbEdhK3RNRTlRWndGeHpxRE83am96bHpBbWlMR3NaaTdVQlAr?=
 =?utf-8?B?RGhTVTV1UGRuaFZleFFQVFptK3pKQU5GUUhTNmsvbitvNEhvM25QbGxHdXZi?=
 =?utf-8?B?WTBlVTE5ZXVtdGdyR0pBckJkUFBva1lib3ozcGw4NU5aVkR1SFJ5Q3g3Z3kw?=
 =?utf-8?Q?FxbdbfIC7FdzrRnOLBTiIpMt2?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 42725d84-1995-4dd5-15cf-08db9282b504
X-MS-Exchange-CrossTenant-AuthSource: DM4PR11MB5549.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Aug 2023 11:30:28.5832
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: BJ8HWuVLBgf91zMtt3GEKwm7qG/K1vFP5qmfoyE/8UCMUnQRrrio184cWqsNQWkQ73zB9gsmi9VqdpApedDTnQ==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR11MB6695
X-OriginatorOrg: intel.com
X-Spam-Status: No, score=-2.2 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,
        RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE,
        URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 7/29/2023 4:35 AM, Sean Christopherson wrote:
> Drop intel_vgpu_reset_gtt() as it no longer has any callers.  In addition
> to eliminating dead code, this eliminates the last possible scenario where
> __kvmgt_protect_table_find() can be reached without holding vgpu_lock.
> Requiring vgpu_lock to be held when calling __kvmgt_protect_table_find()
> will allow a protecting the gfn hash with vgpu_lock without too much fuss.
>
> No functional change intended.
>
> Fixes: ba25d977571e ("drm/i915/gvt: Do not destroy ppgtt_mm during vGPU D3->D0.")
> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
> Tested-by: Yongwei Ma <yongwei.ma@intel.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---
>   drivers/gpu/drm/i915/gvt/gtt.c | 18 ------------------
>   drivers/gpu/drm/i915/gvt/gtt.h |  1 -
>   2 files changed, 19 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
> index f505be9e647a..c3c623b929ce 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.c
> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
> @@ -2817,24 +2817,6 @@ void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu, bool invalidate_old)
>   	ggtt_invalidate(gvt->gt);
>   }
>   
> -/**
> - * intel_vgpu_reset_gtt - reset the all GTT related status
> - * @vgpu: a vGPU
> - *
> - * This function is called from vfio core to reset reset all
> - * GTT related status, including GGTT, PPGTT, scratch page.
> - *
> - */
> -void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu)
> -{
> -	/* Shadow pages are only created when there is no page
> -	 * table tracking data, so remove page tracking data after
> -	 * removing the shadow pages.
> -	 */
> -	intel_vgpu_destroy_all_ppgtt_mm(vgpu);
> -	intel_vgpu_reset_ggtt(vgpu, true);
> -}
> -
>   /**
>    * intel_gvt_restore_ggtt - restore all vGPU's ggtt entries
>    * @gvt: intel gvt device
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
> index a3b0f59ec8bd..4cb183e06e95 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.h
> +++ b/drivers/gpu/drm/i915/gvt/gtt.h
> @@ -224,7 +224,6 @@ void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu, bool invalidate_old);
>   void intel_vgpu_invalidate_ppgtt(struct intel_vgpu *vgpu);
>   
>   int intel_gvt_init_gtt(struct intel_gvt *gvt);
> -void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu);
>   void intel_gvt_clean_gtt(struct intel_gvt *gvt);
>   
>   struct intel_vgpu_mm *intel_gvt_find_ppgtt_mm(struct intel_vgpu *vgpu,

Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>