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: <865abcff-9f52-dca4-df38-b11189c739ff@amd.com>
Date:   Thu, 17 Mar 2022 17:04:48 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.5.0
Subject: Re: [PATCH 2/3] drm/msm/gpu: Park scheduler threads for system
 suspend
Content-Language: en-US
To:     Rob Clark <robdclark@gmail.com>
Cc:     Andrey Grodzovsky <andrey.grodzovsky@amd.com>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        freedreno <freedreno@lists.freedesktop.org>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        Rob Clark <robdclark@chromium.org>,
        Sean Paul <sean@poorly.run>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        David Airlie <airlied@linux.ie>,
        Akhil P Oommen <quic_akhilpo@quicinc.com>,
        Jonathan Marek <jonathan@marek.ca>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Vladimir Lypak <vladimir.lypak@gmail.com>,
        open list <linux-kernel@vger.kernel.org>
References: <20220310234611.424743-1-robdclark@gmail.com>
 <20220310234611.424743-3-robdclark@gmail.com>
 <YjMGac4Hnjmg1wE8@phenom.ffwll.local>
 <3945551d-47d2-1974-f637-1dbc61e14702@amd.com>
 <CAF6AEGv36V8bLoDn5O1SW3iTUtzd3O1XeuT5gJxyLMxd1E-o3Q@mail.gmail.com>
From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
In-Reply-To: <CAF6AEGv36V8bLoDn5O1SW3iTUtzd3O1XeuT5gJxyLMxd1E-o3Q@mail.gmail.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?TS9CajNDNVVaTThxZTRtOVliOENCeEp3TXltdFRsWEQzMmZVRHZ0TG5CR3c0?=
 =?utf-8?B?elZYUExKZ0RLeHFERzhPTnI3QlJRMEQ4TnpvU25pcmNHV05ZdzR4cE5XeTNV?=
 =?utf-8?B?Y1N6RlBxQnNjUTlzcWVKWS9QbC9UeWhNM0pucVlteCt6OFJCdWV1M0h0QnJV?=
 =?utf-8?B?eUREaDZEeWxTU3dMejhzQ0ZCSGxqNmV6TDFqUHpEaGhDSHFlall5ZUVSOW5v?=
 =?utf-8?B?QXdXdENUVzNnMEJZMnJPUFZGSmJMSklnWUJEQW9HTFd2R09wZTBGWnZWUjVO?=
 =?utf-8?B?WlJpYjdvaUJCYnRNUGlnSXVkTXhSMUh4bGtlZDRVNkt4REVBWDF0anZyRTJ6?=
 =?utf-8?B?ZGJYQTJFWDVJTWtHSVB3MVdCNHpDdVZFQ2hBUTFKRWpmTXordjdyNUNaTlo5?=
 =?utf-8?B?SENTd056R3RlY3dnSEd5NG05QTZFelJCek1BbDUyODE5UUw1TjQwU1VXc25m?=
 =?utf-8?B?YkpDUWdQL1EwUlhBTGJ1WVQySmlrRmxFZ1FtZERpTW1BNUFVSTBEVDArMlMy?=
 =?utf-8?B?eHdPNnhvYkQyRXFEM0gwd2pzMWtaU3RBUHB5U2lUWS9pbU96MGY5czdxRC9s?=
 =?utf-8?B?MDBCZXREaU9RSVgwRWpHZVR1N1pHZ3NkcTl2Y0h5QWxRczRqc1hvUzN5R2RW?=
 =?utf-8?B?QWM1c2ZxelZsR2Y5Tko5SS9seDZaNE9zNlc4NU82OWpCVWtqc1F0WDMwVFRN?=
 =?utf-8?B?SUpsaDh5dHBRaXVuYmgrV1ZGbFRIdFJaVkcwdUpNQjQ0SnF5UTA5NG5oVzRL?=
 =?utf-8?B?QVN1dHJ3a0lZRFp5K2p6bmpzdVZPUzg2blpFZ3VKSm5XNlIydHkyTkptU0h3?=
 =?utf-8?B?cHFxNkY4ci9Femp5OFc2TnpoaG1Pdm8zODdoV3ovRjFPUG4yWG42U3dBN3lZ?=
 =?utf-8?B?V0MzeitqN1FNQWF0Ykw2VUN5a0VvQmY0SVVPL21adWJZNDYySGlRNS9WaTlT?=
 =?utf-8?B?azJxcE1vWUNJczFRUjBVWHhzL3orcXlFV2dObTNtZWFDL2s1WlJlb3NNbHBG?=
 =?utf-8?B?eWlvN3lEREpLWjhHd28waE5sTWtWcmhCTVIvNWUxWkhOdlZLNHBFcXJBMWxy?=
 =?utf-8?B?aU1wMDNZVnFvd21DZFJPQkxnd1RUMnlrNEU1VDYxdWlOVWxLUFlVUFdReEJn?=
 =?utf-8?B?RVZkQ2MzOFN5QmFlK29iOGtBZjZaMFBUMmdvdnN0M2hweGpYb2pGaytuc1Zt?=
 =?utf-8?B?VmpYb3ZadVd4b0xQL1haYWNUTUdyb1JrbHp6VnFkUjFzR3ZuRUNJSkt3RzMy?=
 =?utf-8?B?U2FaOVZsd1J2NDNHdTNWOWhnVzdsT2JFektyUzIzaDdtbTYvU1paTVZhejk3?=
 =?utf-8?B?Um0zZEJra2tHbWd5VmpMaTFLZmgzQ1RPVWMwN0hDTGtIRWFva0lESTkzWTNY?=
 =?utf-8?B?cFF0NzRlSmgrT1p0dU5JWExSTThiYkczRVVrTzF4Z2RqQ0hNMG5XNEdpTmtX?=
 =?utf-8?B?a2kxSGtNTnVSMUwzejJicmFIc3hrTStUd1JHUE1veW1Nbm5RR0cwb0dIQW9P?=
 =?utf-8?B?V1RRVWRRZllFNkFrdGFJdTFjNDdhSnZST2ZCTmxaZ1ZBY2MrRHhwWUtvSTFR?=
 =?utf-8?B?YnMwQUZBM3VJaTBOSlMyQXNITWk3bDNUZ3Q2dFEyY0dQMmo3QjNsbnBxeDBK?=
 =?utf-8?B?ckQzalpvZUpQM3hJUmlNUVNMT010QXZISTZuKy9UdmdFWm9uY0h3T2h2OHAz?=
 =?utf-8?B?RElOb2NwRCt6em9EVGhsYVdybFh2bGJ1S1NXMjNxQUdBWFlCRHdJYlNsR2dZ?=
 =?utf-8?B?dHgyRzl5eFdvNTVRYS9DQ3lxVVVoNURJWGs2ci9vK0dmaGZnL1dYOEdibmVI?=
 =?utf-8?B?RTdNd2wwSGVDNTl3YnRDaXFuY2JEMm9iU080aDFnWTl0aUtPWi9HbkFIeVZN?=
 =?utf-8?B?MExiWlBLZzVnTUJ0UFQvajdPdCtleXIyZ1lmcG5DTlBKY2s5ZU9MVW9nMlNY?=
 =?utf-8?B?b0l6WmRnbFNxaVNOR2RXbW9lRU5VQnQ2QUY5RHVxZ2pnZU1lMVFkVGN6RmUw?=
 =?utf-8?B?d1RiRFhaR2o0ZUEzazV3ekhuV21HR0tGV1VobU5yNTVZQkd4ZVZocXE1U3lX?=
 =?utf-8?Q?EwftNK?=
X-OriginatorOrg: amd.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 32b1bf08-6c38-4f00-dccf-08da082fe12f
X-MS-Exchange-CrossTenant-AuthSource: BN8PR12MB3587.namprd12.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Mar 2022 16:04:56.5841
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: Q70awWQXDJ7wLkyQTy3VP53ZW1k7cmopUZDuxsJom1Gv11VP9Vb2r4N7jgg9MwZv
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4748
X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_NONE,
        RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS,T_SCC_BODY_TEXT_LINE
        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

Am 17.03.22 um 16:10 schrieb Rob Clark:
> [SNIP]
> userspace frozen != kthread frozen .. that is what this patch is
> trying to address, so we aren't racing between shutting down the hw
> and the scheduler shoveling more jobs at us.

Well exactly that's the problem. The scheduler is supposed to shoveling 
more jobs at us until it is empty.

Thinking more about it we will then keep some dma_fence instance 
unsignaled and that is and extremely bad idea since it can lead to 
deadlocks during suspend.

So this patch here is an absolute clear NAK from my side. If amdgpu is 
doing something similar that is a severe bug and needs to be addressed 
somehow.

Regards,
Christian.

>
> BR,
> -R
>