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McKenney" , Metin Kaya , Xuewen Yan , Thomas Gleixner , Daniel Lezcano , Suleiman Souhlal , kuyo chang , hupu , References: <33e60181-1809-44e1-bc4c-8ac7f79d49d6@amd.com> <20260327160017.GK3738010@noisy.programming.kicks-ass.net> <1515d405-62fc-4952-842f-b69e2bf192c0@amd.com> <20260402155055.GV3738010@noisy.programming.kicks-ass.net> <20260403095225.GY3738010@noisy.programming.kicks-ass.net> <1d2d4596-93d6-4d87-babc-084b8d6c2d98@amd.com> <20260403112810.GG3738786@noisy.programming.kicks-ass.net> <5e2337e7-24d8-4cc7-a86d-b8f5a19fb3ce@amd.com> <20260403143819.GC2872@noisy.programming.kicks-ass.net> <0f5b0dd9-ef6e-462b-ac89-6f37c4261241@amd.com> Content-Language: en-US From: K Prateek Nayak In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF00012E7E:EE_|IA0PR12MB7507:EE_ X-MS-Office365-Filtering-Correlation-Id: 8663f3cc-231d-4cde-cc03-08de920df56d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700016|7416014|376014|82310400026|1800799024|18002099003|22082099003|56012099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb08.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(36860700016)(7416014)(376014)(82310400026)(1800799024)(18002099003)(22082099003)(56012099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: UkwR+vE/1tSj6v6Y9/F7PZ2yNe8GllbRynAgpUwTx7ZCpVTZGUkcOHF+fOZOnipr0ADOjXmROvkMjAQ/vgPabW8ii2eV3g3LqmRyPoRIiAC/RKXfh2hBajV/8LmyALhzVpXuEvV1VbDebZ9WTzZOvrVgt8HjK0qJVGP21oe8XcYHqv+Bx+bJVZJOkO6CrZbxwt9m6kzPPK6w20JQ6/IBx4WemVzaDoscicAoFguzeDpPUVWeUq/EGD9Hp0lmLZVxIqr5fsc44i6W034+nsLAhQYkxHzRH2anLM7vEVhX80mot8h1lYPXFq0bCgzxNVUizu0OgGmwTBSXGq/AgLCPqQkBUklOqxo0MpoVgentuOyH6WeU12k/LFVASO3I8asFmLudYN4hSBOK4QThQ5zXYDb/uBjF7Abn8RvYtYhB+dljMmOzonKRUCxyWZJl+mB/ X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Apr 2026 05:49:38.2296 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 8663f3cc-231d-4cde-cc03-08de920df56d X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF00012E7E.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB7507 Hello John, On 4/4/2026 5:56 AM, John Stultz wrote: > I'm currently testing with my best guess of the combined suggestions > you've both tossed into this thread. Unfortunately I still trip over > state == TASK_RUNNING in proxy_deactivate(), so I'm trying to debug > that now. > (I think the issue is we hit the ttwu_queue_wakelist() case without > clearing PROXY_WAKING, so we need to clear_task_blocked_on() earlier > in ttwu, likely right after setting TASK_WAKING - that's looking ok so > far). That makes sense! I forgot we had that path for "p->on_cpu". Thank you for chasing that. Also looking at proxy-exec-v27-WIP, I think that: set_task_blocked_on_waking(p, NULL) in try_to_wake_up() can be moved after ttwu_state_match() since otherwise, we skip waking the task but ttwu() will end up marking it PROXY_WAKING for a spurious wakeup. I don't think there is any harm in keeping it that way but during the next pick, __schedule() will end up seeing PROXY_WAKING and will block the task. Until it receives a genuine wakeup, it cannot participate in proxy which is a missed opportunity. > > After I get this into a stable state, I'll try to polish it up a bit > and then re-layer the rest of the proxy-exec series on top (I do fret > the sleeping owner enqueueing will be more complicated). Ack! Let me go stare at it for a while but since you say it hasn't outright crashed your system, you may have taken care of everything already ;-) -- Thanks and Regards, Prateek