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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6AB5ED6AAFA for ; Fri, 3 Apr 2026 02:06:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0E57D10E081; Fri, 3 Apr 2026 02:06:24 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Y/hbBaxc"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) by gabe.freedesktop.org (Postfix) with ESMTPS id E33FF10E081 for ; Fri, 3 Apr 2026 02:06:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1775181983; x=1806717983; h=date:from:to:cc:subject:message-id:references: content-transfer-encoding:in-reply-to:mime-version; bh=p0Eurj4p6I0f9ECefD6klnXUKi7NIrEqbMPiv6W17vk=; b=Y/hbBaxcasC6ya6pW15Fu8q4PlTHu2kjYQu2pKqTxN9STNXoQWUhH5B7 ayAyEalCBpNY4SHqGJe6ArVfYJUs3eadeCS3O5PLktHHM2X2EnoEuQHir sbSADsPvhK4ZaW1DqeACYVGc3Ddvjjgr8qq/qU+DONBjD59nN/bcBniNr UREa24C9OiteraS+LSsYbJsIv9OK1vDA5qhZwgoj6pi0sfrfSbdZlMA23 6TL4es7+EBhpN313mwQb+7R4gyf5IpU6LwasKeHjxU9/uDfrlffAJq3KX xpICiLkdlgLHJEhjObl0tda9p6v8x77AbSz3cnUNiktOtlR3NBXu0X5/T w==; X-CSE-ConnectionGUID: LRq1tfBTTRiv9evdG25/Lw== X-CSE-MsgGUID: 0yjr4sROS1KoVaria0tUsg== X-IronPort-AV: E=McAfee;i="6800,10657,11747"; a="76141535" X-IronPort-AV: E=Sophos;i="6.23,156,1770624000"; d="scan'208";a="76141535" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Apr 2026 19:06:22 -0700 X-CSE-ConnectionGUID: NyVadHv3RrGnoa3lVqGcVg== X-CSE-MsgGUID: fbMw0p92RIybLXQUnfB53Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,156,1770624000"; d="scan'208";a="265070702" Received: from fmsmsx901.amr.corp.intel.com ([10.18.126.90]) by orviesa001.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Apr 2026 19:06:22 -0700 Received: from FMSMSX903.amr.corp.intel.com (10.18.126.92) by fmsmsx901.amr.corp.intel.com (10.18.126.90) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Thu, 2 Apr 2026 19:06:21 -0700 Received: from fmsedg902.ED.cps.intel.com (10.1.192.144) by FMSMSX903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37 via Frontend Transport; Thu, 2 Apr 2026 19:06:21 -0700 Received: from SN4PR2101CU001.outbound.protection.outlook.com (40.93.195.6) by edgegateway.intel.com (192.55.55.82) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Thu, 2 Apr 2026 19:06:20 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=dU4hw+B/D0z1uAbqPdahU20odTSE+ViVGTO8o9RX50B1ppaYZis/hWC0A+p2ujYaA1WmDkYKymg7gNcHgmj3TPe1bm6G+1tZsPz+qU0dLIINVL/60n4L1fEjlknXLETmg6MH4bfGMIrG9RfN1aNrU3KmQpP1qoXqw0pCJ7I9mNOawO2Zl8RP+ESHyTqvmExpTR175X6rLMAIwyt4iCNnSUOIsTwHv4+YcNaQktggrBtPRaorYzwsV1PcwdGu1sFN1aWXae8V1T9gFXE9rQzlwSa17GEBYsezHrT/YEr6Mfk35PZJF/zU2eKOf9J5UzvIWOI6iTEVuc7OZ/BoyJxE0A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=eFKSip45LXZyCxGPXL3EZumnPjLLKJlYfyyB5DcLrNs=; b=FRXkSD3HSRUtpx6hkd4cUQu+AKO3WERpfu+NrwGRxO5H/WZEZ/fwyBmR/8zCH+bMavhuGN0sgA6/1Y+yhAX0FNmsYyY8isM2ElvxDUBBC0yYHvvek3JTKGxB846nfmAcwx9+Bd4sSmu+nHpKURSnK6wS7fPf8/NigQ4tEEqg4dQ7/pZhhQmhqZbn/E1xAr5r+vvC8fBvDFf8A3z13zoua4vPUJXyq0aCxK5NfSZgBUIpN4vnqSJcs76Lq+w5o/QnhfsTXokdvSg5+8JWCQiL+bFbk9I2k9FQ/mp0IhyiB+fhwqMN8l27wlPDep2EG52nDqf7z08mtypcVP6BxM6cdw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from BL3PR11MB6508.namprd11.prod.outlook.com (2603:10b6:208:38f::5) by SA0PR11MB7159.namprd11.prod.outlook.com (2603:10b6:806:24b::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9769.21; Fri, 3 Apr 2026 02:06:15 +0000 Received: from BL3PR11MB6508.namprd11.prod.outlook.com ([fe80::53c9:f6c2:ffa5:3cb5]) by BL3PR11MB6508.namprd11.prod.outlook.com ([fe80::53c9:f6c2:ffa5:3cb5%7]) with mapi id 15.20.9769.016; Fri, 3 Apr 2026 02:06:15 +0000 Date: Thu, 2 Apr 2026 19:06:11 -0700 From: Matthew Brost To: Himal Prasad Ghimiray CC: , , , , Subject: Re: [RFC 05/15] drm/xe: Implement xe_access_counter_handler Message-ID: References: <20260318074456.2839499-1-himal.prasad.ghimiray@intel.com> <20260318074456.2839499-6-himal.prasad.ghimiray@intel.com> Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260318074456.2839499-6-himal.prasad.ghimiray@intel.com> X-ClientProxiedBy: MW4PR03CA0093.namprd03.prod.outlook.com (2603:10b6:303:b7::8) To BL3PR11MB6508.namprd11.prod.outlook.com (2603:10b6:208:38f::5) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL3PR11MB6508:EE_|SA0PR11MB7159:EE_ X-MS-Office365-Filtering-Correlation-Id: a370acad-c522-4f4a-abd3-08de9125963b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; ARA:13230040|366016|1800799024|376014|22082099003|18002099003|56012099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:BL3PR11MB6508.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(366016)(1800799024)(376014)(22082099003)(18002099003)(56012099003); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?dHdvSG04YkpqWVlWYzNRUFIwTDVwU3NuLzl5QVNqbzhvaWt0UjlXTTVNcmdm?= =?utf-8?B?Y3dWcTFEUHJGMzdoSWxxcXFYQVU2QmczRU8ydFpNZjhQczh2a2VDZlcwTW1y?= =?utf-8?B?c2tiUDR5YS9yc0RBTzlldjFySnBiUGF4WUc4clBNVDdEZEVCeDlnbWdWZmhi?= =?utf-8?B?bGhqMFAvb3pIVUdvK1h2NlZBTFFtTmJ2MDhleUtUQ2lqN1lLUlFxdmFHMEhI?= =?utf-8?B?NHh5TktoUmYrbzZFYmJaOUVtRjM4dGErQlBkQjhuYzBwRkpPcjAveHYxbVgv?= =?utf-8?B?dEtwem02aC9ITkkwK1l0T0RDTFBXeVZWVGcxZ3IwWERQYlFCSDNwVDJnRElk?= =?utf-8?B?c2RpWkQwdE9FOElzZFdKdklTZHFwWGU2TzhYMldsQ1hSbGkrdDhBRG9vTW05?= =?utf-8?B?bVVsMDJoYVVEb1ZsUlFIS2hKZi9SbDBqZDBSbTdndnNVdkw0bnRvMkc3OC9n?= =?utf-8?B?dmNkbzNHRFpIVFlJd2VxWG9CcnN4V1Vxd2ZHdk5NV05meVExNmNXa05ubjIw?= =?utf-8?B?WG5KQ3EzMlppYzYwMGVocW03ZVNzZm9yYTNmQlV3b2FBRkNRRWlsTko1N1VK?= =?utf-8?B?WlBGYmRuQmcwb2hJVmkrSFdpaUpUNFVlNzR2WkFtUUN1TDdhYWZ2S1NBTHBs?= =?utf-8?B?NFBRYzVXdmRDMkVsa05jcUN6NDhVUVk2b0xFMG56NGxrUUNSY3pqc0Z6Q25t?= =?utf-8?B?N0VtR29WdUlOVWdkVU5zZVE0bVpNUjVpNHNLaFptUEd2T3duL0dVM1F1NzZy?= =?utf-8?B?S241TW9aLzg0bjFpNGdWdWgrbkthNHRyYjhnNTA2aEFraTZBWWJvODFhRUlP?= =?utf-8?B?WEIrZnZTdnFlQXJxWDhUMVRBbllnZHhuN1Z2aCtlS1ZHTUVqZXBTL3pVb216?= =?utf-8?B?WU51czJIT3prRldXTXlrSytVUHJ3VE1xVWNOMmNoYlZSZzI2WGZ5VmpTdlYx?= =?utf-8?B?WnRWd0cwZUU0YkcwTGszSkkxck90VnRNdnB1cncxMDh5RDFjNVlNbEtFNUpB?= =?utf-8?B?Z2lEWmx2ZWFhNUQzdHE4V2xzc1ZiYWZvMU15NldCYld6N1NGalFkSytuMnZh?= =?utf-8?B?d3cvRFZaaGp0TzBEMXRhY2pEbVY3TWpuUWRQUWRDaHFkVGo5emxBRjQ1am9l?= =?utf-8?B?R2J3SnljVzdzbjhFOGs0c3FaNzM3eFdqWlpxcXBSNE44ZDFhdVk0L010Rm1v?= =?utf-8?B?aCsxcUkzUWFhTDFOVmJNN0tPYmlrUjZkZEVBMnRtR2hHMGlTQkpnZngyUWNp?= =?utf-8?B?dWdVQWdJcGhkL1lOYmVUcXc4b2VOUTF6YytSdXltTG9qSVlhaStUQ29IWDdV?= =?utf-8?B?d0ViajFZMlU5dU9yM0MvSEJERldiRFFUc1RQQ0ZrZE1xL0NtMXZ6RWYvdjdt?= =?utf-8?B?NlJRMUVBSmc4WTZGV0NWdE5LbWpuK1BXN3Ird3g4czlGbWd2UGcwWG1tcFNM?= =?utf-8?B?Ym9leWVIMFY0RkZxcVYxVEVLeHlWYm1sellCRnMwdG11d3JVRFVBSTU3ckdS?= =?utf-8?B?SnNoYzhJTHZ2K2d5T1JHdExmYkNuWUZBYmJucHNpbjJnaTRYTGlPT3dGc3VO?= =?utf-8?B?bmxkYit4NHhjWHEzTjVDQTgvZGcydTdOQXovVmlpa2NOd3Y3dnMyYVByRStq?= =?utf-8?B?a0tOZnBNSFhSbGtoaEdFMTFSVjNyQ1hDVDdGYytwaThDZjIzaVU4ZkRtRU1z?= =?utf-8?B?T3o0WWVMbzhmbTBTYnFRQWoxelI5SThGb3B2ZlZuQThZb2c3bVFGSHNiVGl0?= =?utf-8?B?TE5RTE9uMVhobmFsaDQ1YUcrREZ5NStKL1JNYUx4ckFvVWlSOXcwanhHRGZP?= =?utf-8?B?dWxyeE13dEdVNFlnU25NQ2l5U3BTaTJYUXgrUm5xTEUwMDhEVkc3bjRwNFJL?= =?utf-8?B?RmVNM2FxZS9nWi9XRDcwdzZwL3ROTExubU5XdXJGOHc1MjUyWCtkSytJV3BW?= =?utf-8?B?OEhWR2FqeTg0MmxqK1NSalpmRFdpdExPQjZJSHM1dTlqdVk2eUpWVWF6amRH?= =?utf-8?B?QmM1cC85TXJUczdWM3NWYXVuY3Ira0o2ZVBjRFdKNFJhVm9mcnovaDlBc3g0?= =?utf-8?B?MTRYVHNMZlNPU2hqeVRJVFY3dzNVYnFSdG50SnhRSHZvNEJHbTRNM1JOWTlz?= =?utf-8?B?QVpXdXg4ZFA4TnVpOGtUOHJTdFIrUjNoWEJ0TVZVOTErdXJWcldwdXM4R2Vl?= =?utf-8?B?U0t5dm00Mi9VRitDd3FRN0FvSUg3alJkMlU5YVRRNVVLakdSNnd1VHkwT3dj?= =?utf-8?B?bFBVWGJNMW1FTG4xNGIrSk1XZGVSd2d1UCtOSzZvamVMTmkvOFdzcUZXSW1U?= =?utf-8?B?U2lDZDJsRXFGN0Nubjl6aktuV0JsZ1FkMy9EbjJ5Zi81by9xUGJJOS9RQVN4?= =?utf-8?Q?dhjY/X53m4MCy4Zg=3D?= X-Exchange-RoutingPolicyChecked: X0e3uIvTVEEMqLDCqI8FsmEFwyyNK5ZJOYejOlgWYBF9+JgK37fsSDq5oppeR2Enf5FG7MkRbS2Ce76SASFhytmkucPwDXDua5Hc8ba6de5X3VQmqnEIqGkxsNyE8hQgxsNM8p92qdigSJAIjOG9D6uURnFlJQ4SICGP+H+sDxB/TWT/hBn7+oCA0AUUi4WEZVxgbCkw/MaE8/iwy5x7PvdA48890fSyWXAvQa0UtZG0pbYYZtIr/IjsA0aZKK1z/SUYTDLkZCMzknNf4ZRnEATglm+qvbipXv2TbA9lbquhNtklwsZ7SFKNUHFOcGMoN7NhuYW11tkjoJopPEKt+Q== X-MS-Exchange-CrossTenant-Network-Message-Id: a370acad-c522-4f4a-abd3-08de9125963b X-MS-Exchange-CrossTenant-AuthSource: BL3PR11MB6508.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Apr 2026 02:06:15.5546 (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: KRYVxcmOdtAnFAVlPMxu5HKmxLU9p/q1MHMul0s+cfJ1BNQ3bHHxuEEfXtDo7yKPEDuYGS7OZCls9Dyqhq5AYA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR11MB7159 X-OriginatorOrg: intel.com X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Wed, Mar 18, 2026 at 01:14:46PM +0530, Himal Prasad Ghimiray wrote: > Enqueue access counter notifications to the appropriate queue based on > ASID and schedule worker to process them. > > Signed-off-by: Himal Prasad Ghimiray > --- > drivers/gpu/drm/xe/xe_access_counter.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/xe/xe_access_counter.c b/drivers/gpu/drm/xe/xe_access_counter.c > index cafcc42897f8..a2ce9dc45d05 100644 > --- a/drivers/gpu/drm/xe/xe_access_counter.c > +++ b/drivers/gpu/drm/xe/xe_access_counter.c > @@ -87,12 +87,29 @@ int xe_access_counter_init(struct xe_device *xe) > * @xe: xe device > * @ac: access counter notification > * > - * Process an access counter notification from the producer layer. > + * Sink the access counter notification to a queue (i.e., a memory buffer) and > + * queue a worker to service it. > * > * Return: 0 on success, negative error code on error > */ > int xe_access_counter_handler(struct xe_device *xe, struct xe_access_counter *ac) > { > - /* Stub implementation - to be filled in */ > - return 0; > + struct xe_usm_queue *ac_queue = xe->usm.ac_queue + > + (ac->consumer.xe3.asid % XE_ACCESS_COUNTER_QUEUE_COUNT); So again, let’s go with a single-queue [1], multiple-worker design. Also, do not pick a worker based on ASID hashing, because once we move to fine-grained locking [2], we can service access counters using vm->lock in read mode. Yes, BO-based migrations still need the VM dma-resv lock, so we would serialize there, but given how BO migrations and binds are pipelined, this ends up being a relatively small window unless we wait on the migration under VM's dma-resv lock, which we don't need to do. SVM or userptr (assuming we implement this eventually) access-counter migration would remain pretty much fully parallel on the same VM. Matt [1] https://patchwork.freedesktop.org/patch/712591/?series=163429&rev=1#comment_1317960 [2] https://patchwork.freedesktop.org/patch/707294/?series=162167&rev=4 > + unsigned long flags; > + bool full; > + > + spin_lock_irqsave(&ac_queue->lock, flags); > + full = xe_usm_queue_full(ac_queue, sizeof(struct xe_access_counter)); > + if (!full) { > + xe_usm_queue_push(ac_queue, ac, xe_access_counter_entry_size()); > + queue_work(xe->usm.pf_wq, &ac_queue->worker); > + } else { > + drm_warn(&xe->drm, > + "AccessCounter Queue (%d) full, shouldn't be possible\n", > + ac->consumer.xe3.asid % XE_ACCESS_COUNTER_QUEUE_COUNT); > + } > + spin_unlock_irqrestore(&ac_queue->lock, flags); > + > + return full ? -ENOSPC : 0; > } > -- > 2.34.1 >