From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD918345754 for ; Wed, 29 Oct 2025 16:07:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=67.231.153.30 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761754077; cv=fail; b=n6t0WzuuF8z/kzsPeZrZgD+lQR4TFfGG+dv2CO+D23pW1TG7Bc34ULMpfiThCIpI4I/0/11HVeqpEPBRE5Tfr1RBrkeNsY36QrOFtEXkmjw6xE3+c3SPWKn6DQ3l7D6oPTBvgf51JnY85qfmlHakbTLj2FVtsn/mgji7ycHJ9Oc= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761754077; c=relaxed/simple; bh=KiKnOAybF7KlHotASNUQqLyiBvJqY6+GonhfcociQqs=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=UDO0LXCuik9pxzkDzXFREmIWXQUMMuYWjBXVLR2wwZC9nXHNyB3JcH9ZJX6/3pnZF3C2mShxelJsRz+ipcnvNqMlReNIXIoUN+wwTIZUs3qzF1ibtTPu6mUyEnJ020paIIlAks+xs8UgwF1C05tjBFXItY9nsXeSJj09U0iN5nA= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com; spf=pass smtp.mailfrom=meta.com; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b=PoTHz7Da; arc=fail smtp.client-ip=67.231.153.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=meta.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="PoTHz7Da" Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 59T9geiL2010276; Wed, 29 Oct 2025 09:06:44 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=s2048-2025-q2; bh=pEJgbpoLwjeryNYDwuCRyLWcGF/WQIlbs2qVOXSSYCc=; b=PoTHz7DalUcn KNebVGqyFrlGWMUM2viCO2jBeh9gwwK9AdQchwy6e1EnVM1XCpnshceeEZNLjupL Ti3LA8WvGC90mc6+tQA4KbV6pSKzhuwGMd9PytmS9VQDKZK8t004Wz0Zd9EJRXpZ swjr3ciZRw1mUp0042zosb8FwU4yA79xjtNgV82/l54Gv/Zl22s0LyDM111q6qr4 SAzAVtskjYnNgs1JQWlt8UtXbVUrlViN9VhHvR9plyxQsLP8+liok02/Jvj+6JMA Sx5Kv+RYyJKaYSNFekm6q3eu1rUnNGHu+HcaQtoGHtbTUxFi5B1i8x0mAUz+fnEK 9T3OKyvVGQ== Received: from sj2pr03cu001.outbound.protection.outlook.com (mail-westusazon11012034.outbound.protection.outlook.com [52.101.43.34]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 4a3ghkaqrq-1 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 29 Oct 2025 09:06:44 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=RzBcW6dDYU/AtRdAt4vF/P2rL4z7IZRJLlBAh7GpUCCcawhddLlYdHRkrV3WktB98t7f0A/tLCS04OcH/2/mw5n0+Mlbqo6PqbErJ4o6o3fg4qLdqt603WfON0TjDV4U12pp+qy4henhkemkr8A4VSWm+RdlcAfxMLBvIPLhELhQ2qSg0b9TXW1us5ANcIu8ThYS8QjjuJ43Y8if1fpO9VHm8VlJoJdE+3kc6+2uoH/qLkPRlfjRHeAJru/BswziO96ErvOHZQ8q8E1Rgpuc+GtSeO0UBUkdaN+iZWL7Y+Q0TrH+d0WyI3b2FFypdIS0KMKvThjiumcZysrkCnlkBQ== 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=pEJgbpoLwjeryNYDwuCRyLWcGF/WQIlbs2qVOXSSYCc=; b=vZ2LKBLlRzHPgZrQcn8M9OD00bOKzrTALnAVA9mP1X8Q1sfkpoMOaPhJAPGCR3r0eRFHu7eeGU9C8c4LnlHHrawIXTiJUxxJg5f8Sg3fJ2dI3ussKpb4VG766FxujnlnnVNWViIh3Jiq5rJIk89p7Hhz4A+A1Y8Kubj9+uprVljiM0YApvd2Vq8KGPN/8L5XwodufsRmrUIt8sT1NNkZ7bRkarWANj5AYu/hpX5HxDG/rY2PTWuG7qyzwCs650utgnfHU8x1SB71aZWo99awNtoME/N6QRxVLvNKJbc3LvDgs8Mje3xRX8bmtTaZTYnnDnwDea5frrMNH8ax770fOQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=meta.com; dmarc=pass action=none header.from=meta.com; dkim=pass header.d=meta.com; arc=none Received: from LV3PR15MB6455.namprd15.prod.outlook.com (2603:10b6:408:1ad::10) by IA3PR15MB6581.namprd15.prod.outlook.com (2603:10b6:208:526::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9275.13; Wed, 29 Oct 2025 16:06:39 +0000 Received: from LV3PR15MB6455.namprd15.prod.outlook.com ([fe80::8102:bfca:2805:316e]) by LV3PR15MB6455.namprd15.prod.outlook.com ([fe80::8102:bfca:2805:316e%5]) with mapi id 15.20.9275.013; Wed, 29 Oct 2025 16:06:39 +0000 Message-ID: <09f7013d-b096-4828-a2f8-629c0a054176@meta.com> Date: Wed, 29 Oct 2025 12:06:29 -0400 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC 02/19] slab: handle pfmemalloc slabs properly with sheaves To: Vlastimil Babka Cc: Andrew Morton , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Uladzislau Rezki , "Liam R. Howlett" , Suren Baghdasaryan , Sebastian Andrzej Siewior , Alexei Starovoitov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, bpf@vger.kernel.org, kasan-dev@googlegroups.com References: <20251024142137.739555-1-clm@meta.com> <51cfb267-f4f4-42b2-b0ea-d29d62bb1151@suse.cz> Content-Language: en-US From: Chris Mason In-Reply-To: <51cfb267-f4f4-42b2-b0ea-d29d62bb1151@suse.cz> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BN0PR04CA0138.namprd04.prod.outlook.com (2603:10b6:408:ed::23) To LV3PR15MB6455.namprd15.prod.outlook.com (2603:10b6:408:1ad::10) Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV3PR15MB6455:EE_|IA3PR15MB6581:EE_ X-MS-Office365-Filtering-Correlation-Id: f4c28d8f-1b46-4e32-2355-08de17052465 X-FB-Source: Internal X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|7416014|376014|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?UmpIbWYzSHBDcDFzTVBmVzYwL2JMOVNBcmVkS295V1dPQmlDUm1jMThSQjh5?= =?utf-8?B?OGVxVXNrVkN0RHp2VitUWXZWMm8zTWdhL25HUnRabFpFRHAxQlFkbys1VDhh?= =?utf-8?B?VjZ6TjVNb01VcFo0dFdHbWRhUFBxMFRsamJvQWxaRkpPVCthZWRGc21RNkI5?= =?utf-8?B?T0RCQUYvWHNBY3l1RGlYNWt3b1ZJWVRHSVlVUm1sei9ETlJ6cHZnd3o2dlo3?= =?utf-8?B?RFlNZHV3Z0FVcmJZa3BZOGw1Vmk2TnE1NjZvcXdzNW9UL0ZYNjR2cHRRb3g2?= =?utf-8?B?ZUhwSCt0c2tqQU9JaHF3RjV3T1JFczVtRnRtV1AxTXMvWktiV1FGc0ZTdzZw?= =?utf-8?B?VCtad3NVUldvTm1FdU5DbGs5NnFlMmNIUTVGUXY1SlJJOU43bnFMaFl6dFFv?= =?utf-8?B?UW16WGhBZUs1cGJOVTVvZUFBUUkzbnUreEpZczNkT1NPWmdzdDNSOU5vM2U0?= =?utf-8?B?M09WdWMvdzR3eWNGZC9ZZThMU2NvR3VoVVNhcFdWaDJneXNTelNpUjZhTkkz?= =?utf-8?B?RFB1cGxDcUxER3lxSDRvZFVZK2E4TEF1SUhrNE1wVlRnUllyZlBXZGtoaTN1?= =?utf-8?B?YytXWkphM0xnYnlzNnY2dWNuWldKRmdRK2ZpMVFIMVAyUFF1ZEZBa29NNktI?= =?utf-8?B?bW95MlJGWnpEM095UThmY2paalBrU1BPTHluSDB2UUNVVjF6SkJ1a1BRSUZq?= =?utf-8?B?UVVtRVhQUWF1QmRHczNNdVJjV0xKQnErd1E2enZGUGNMN1ZUc1JsbDdRdUdu?= =?utf-8?B?cjhUM3NmK3V1YjliUXVDd1RaMWlXM1JhV3B6eHRJM0E0S0JCUlZyL0k3ZUJx?= =?utf-8?B?aHNCL3FSU2ZEN1NCdGloMzV1S3MvdjFKbDlDTXhXVkUzR21JYmhlMlk0YkdJ?= =?utf-8?B?b3krTWdEM1pDaHBMaVZuRkZKeVJoeWRtaTgvNlVZcHNSQ2hIMVZ4MmtrYXB5?= =?utf-8?B?NU5OS3hHRXA1bGgvc0tHRlZCbFBTdzRKS3JnM3ZFazBZNlNVQUVwOXp3U0hI?= =?utf-8?B?NzlINmgwV0VZNXJrSnBWNm5WU3YxanBwbG1iRFZYY2lHazFoUzB5c3hsbGlq?= =?utf-8?B?OXFkOG82RnZ1RGhTU1FRR3padlMrMUh0WkYzR3BNOFZwT0RmQVNwUWtmOUlP?= =?utf-8?B?Z1dRbFdzTm45dC9JbHY0dm1OWlNvbHdMakxYaWV3N1JKWDRvenNLYk1KNFgx?= =?utf-8?B?RHNCa3FCUzVocndaUnVFTnNOVGVLNzVWcnZ0eHc2aVEwbmdSWXhnbkcyRDI2?= =?utf-8?B?WGR6OCtHZWV0eUdlYXZrOU9WQ2NsQWpJN2Fvbk56MmpLMEJsWFVDZWpVU2Zu?= =?utf-8?B?OVBEbkZLN2dWaXNrdHZTS1V6SlEzeThPakhvV29jdUVyaWhpU1J1MG5mSnly?= =?utf-8?B?QVJVa0ROdW80bnhLZTA0a3paYTN5UEpuVjdzN0FiWEx0WGVZdW5NQ3VVbzAv?= =?utf-8?B?Y0VJMDdiZUxhK0lOaHU0dXJzWUYyV3VmaU82ZXU4aHc2VWJydUZpYXdlQjFi?= =?utf-8?B?TnQzcHd2YWdZTnZMVVlTVFZqWTBvUTFIeWJ5TXJUTk93MkhaOVBlaUNCYkF3?= =?utf-8?B?R096b1dXT3czMDUwTlJlZkJOTG1BNEhtYkNqUjdEVDlwanpOMDJYZTZwTExY?= =?utf-8?B?TklpQ25jL0x6aTN0ZnBVNjJqZ1k3S3FyYjFHQUtqT2xPZUJ6eXg1MktURVdU?= =?utf-8?B?SEdSRVpZNS9LcFVGRnl6aXNQQ3F2S2tpcU1oV1FiUEYySGpFVmVSMmZkZlp5?= =?utf-8?B?SWZiaTQvbkJnNVhiaU1OTnNTSGlpVWJCczJnOTBJTG03Q1ZSdnQ0MjFJay9k?= =?utf-8?B?MzZmOGR3V3Qva29vRXE0UUR4Z2xPck9YMzdzcUtEZXlNTEozODh3SVNHMStY?= =?utf-8?B?LzIyVHZxUTdOMjZFcFhYV1NuSVREY1E3Q0NIT2oza2x3WnZiRzAyaUkrbnRz?= =?utf-8?Q?zG3RZfPbR2lTDAgbi3NTmMvUoCS/cIyH?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV3PR15MB6455.namprd15.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(7416014)(376014)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?YzVIWHNZVTFnWHI2NWhrbUtQYU5qY1RldnpZc1FEaUhDcjNZdnZROUpJYTFV?= =?utf-8?B?SUt6TWxBQjFHOVJvV09yTkJUT1NTbFppNkwwTFJpZDFQRFd1alZVQTduTm9l?= =?utf-8?B?YlhzL0MrU0ZiQjV2UDRyZkowS2RXY25LcUZNM2g1Qi82NDA3VjZibUJ6V2hh?= =?utf-8?B?a252SCtiayt2V2FKUXpDS3RVTGtQUy9WMEVkdkh2SUxJWnQ1djdZL2IwcFpH?= =?utf-8?B?SzQraXBpNUpxYlluUkhRZ3Q0MFNlQWl3ZGxRODloR0lNdWRjRmdhNWxidWlk?= =?utf-8?B?c1lkNGtUWUhQRTRlTE1OWk50SWVqWEE0M2huOGUwZC9QTEVNMFJPS0NaMjhP?= =?utf-8?B?eDcvVUJ1dGxOTlc1c1l3ZVlKS0hVUk1vYmdQd0phWnZCc3lINTd4ODFtYWh3?= =?utf-8?B?V29qVTA3ZlV1OWF5Yk9nS0VWY1AwakZJZ3l4OWxHazEzWEF2ZkNmZHFYNS9v?= =?utf-8?B?WEo1cUdLVWw5Vm1zVjVhS3NNQm5jYnpTbG53d3ZiNWlFbWlBYXg1a0VBb2dD?= =?utf-8?B?L2Q2MTBJZE5ZOU92NnlCYUFPa2Z5N3hrSE9wZDA4bHNZU1lWTU9nODdZYWhU?= =?utf-8?B?eDJKUDUvV3VFVHJVTGJZVW81ZzduOXFpUFZ5eUpDcDlIZURhRUcyRE5WRHNS?= =?utf-8?B?c2pBR0NWS0hiT0sxWld5WXJOelArNFNSZ3Q2eVcrS3lOSSsvR203d0RmTnpP?= =?utf-8?B?RURZeE0rd3E0SG1qOEZlVzJycnVaa2NpbmtxbmRydFNxY2xRTGtWanpUVldX?= =?utf-8?B?UHRRWnNldjFtRXM5QUlreXVId2owZm0wY0RCR2NtQnZxM0ZzSWlyRzRiOGhN?= =?utf-8?B?UWw0Z3Fhb01TZFI2eWRjSWcvNTJRK1J2UkVUcDMwOG9yVVJYcG9WT3owTHEz?= =?utf-8?B?N1V0aTdIMDBMNXduSHlONzV1bmczN2Q5WWNiOERaQk9RSzJodDJKaDlmSE9v?= =?utf-8?B?Zm1WaVFNQUdhOUFqZjdybCtEUFdUOHpON2F4Nld2YXkza1NpUForaXRhR2wz?= =?utf-8?B?bjVlSFBjMTFVVlBoendjc0ZnQjVENGVjR080NW5TSkxKUUxpOUhrRTdKMHYz?= =?utf-8?B?Yi9RdC9nVGRLUjgxVW9wUGIzc05vNWNzUFBkdkhNMmZqaDE3Z2U3VmF6dnY3?= =?utf-8?B?bjRmeVZLRklockJXZFJrMDZzQ0x4MEMrUVpzZnA3UjhNRXUyZW1yZTZqZitJ?= =?utf-8?B?b2pjUTJWS2czRXIzR3hJZ01iZ0Z6a3RWQjJQOTlSKytPUnhxYUxuNFZVdGE0?= =?utf-8?B?MXBDWHhFYVlOYkRieXAyN1djbldjSHJvMnFUMlBQM1JEYlVzWG00L2Z4clQ1?= =?utf-8?B?cEJUaDVGb3BTRk1NZWp4bW1uR1FrUm80UUlTWUM2OUhXYVNjZ2M3T1ZvU2ha?= =?utf-8?B?bTFWZlA0YXVLNGF0bGNDSEl3REhqRlN6eHlJRExhOVd4TlJvU3c4STMvQjJs?= =?utf-8?B?YmdjcktCNFB1TnM0MDFBeENtdTJYeEZLMTV4Rm04NXZZNGxYSEZBZDU1YWZh?= =?utf-8?B?ZTAvMGw1NjJ5MGwzTUl5b1NuR25scllVdCs5NTdKRGFod0VJZW9KK2NSNE9h?= =?utf-8?B?cS9nb1c0d3BwMk1ZdGxMV2lXVEh0cTZLaFh6T2pKQTZUZ0VJTWtGUDdWRVdN?= =?utf-8?B?dHdsdFZTYUlKU2ZFUzd6ckUxWE9Pakd0UTVCazJUa281bElzeXJ1ZDJLK1ZW?= =?utf-8?B?TVFBa3N0c3BRM3VEZjhCdXVFSGNZck1QY2s5cE9XMzIyOEc0TXBwamlRUElz?= =?utf-8?B?TUhlVUJzRTNPaVo2R3Zxem0xREtqblUvaG9ZaDdKMXRuemdUajlzRXRTTTNz?= =?utf-8?B?ZWFmTkpwdkhCUjJPdmxnaW9VRU1WMmVlZzFzb0RVdFBBMkllS3JzbzFrdGdR?= =?utf-8?B?YzU1TGRvQlU1M2lkckFicEJZTHlNcmVFNUFUNVdWMGVkS0l5aE54ZVpNc21x?= =?utf-8?B?U29jWlU1S2hzT1N4WmNuVGFwU2FtSlZmZzV4RXlUVXN5RXRYUDVZdXRsUkUz?= =?utf-8?B?NzltMERnUWxJdmc5N3k5T0hMWHM3TFp4YUZEYTVwZzNGRmFzY0o3T2ZMMEpE?= =?utf-8?B?d3M5L1ZuMmkrd0JwYnhMVnBqL2czd1dFc3F5MWhReEExd3RieEhDeXNWUGUy?= =?utf-8?Q?WDK0=3D?= X-OriginatorOrg: meta.com X-MS-Exchange-CrossTenant-Network-Message-Id: f4c28d8f-1b46-4e32-2355-08de17052465 X-MS-Exchange-CrossTenant-AuthSource: LV3PR15MB6455.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Oct 2025 16:06:38.8855 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: D9JUd9xYg2t76Sg4tAFand1YgkshhcJlg/6K+7pFdsR6Ju/4d10nGpbtaiAWzSBy X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA3PR15MB6581 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMDI5MDEyNiBTYWx0ZWRfX5ZxpCrSXLjUk 3v6vR3HgPiG2CUBPCPD03Z25v2DVGvl+LQvyvBzFblOXOln/9ukz46GdvMWQQRvi/159FzRAql4 GuIUVxyUhH/wy+JwAjNqHyd/Rb8bPSoEblfzRENpZX/YvpNhjMDrQC2P5rHsHCiEDipDooVdo2d 365Uz0A0jWt4kaD792L529PQwHRjZRR44BFL5NHDOw28KG7cyp5+sj8PC/xWvb7G2csFUsV/BI+ 4iNzCEZ/C/bI3GRuLewPCYdmyE78+yhkjO8AoAJYo63P2q6vwRq5kOkbR+gQkhtHm++xMLJ7nYY 2t32aD+XFdglA65EWWjkiHmTKFf9Sw/G3S2k9jlz9ctQ2XJTS75bVOkqhscoTvj41nIZw60pUfo xUeDop3j/WDWyyXQigu7DVwBz5+Pmg== X-Authority-Analysis: v=2.4 cv=CaUFJbrl c=1 sm=1 tr=0 ts=69023b94 cx=c_pps a=e7UpQLGcWimQYEoqUdNrWw==:117 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=x6icFKpwvdMA:10 a=VkNPw1HP01LnGYTKEx00:22 a=zvOSfKsmGlIUmWq8E-oA:9 a=QEXdDO2ut3YA:10 a=cPQSjfK2_nFv0Q5t_7PE:22 X-Proofpoint-GUID: JW0Ww1s4YXaKu6JnEh-jZp0ioF1AAnoe X-Proofpoint-ORIG-GUID: JW0Ww1s4YXaKu6JnEh-jZp0ioF1AAnoe X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-10-29_06,2025-10-29_03,2025-10-01_01 On 10/29/25 11:00 AM, Vlastimil Babka wrote: > On 10/24/25 16:21, Chris Mason wrote: >> On Thu, 23 Oct 2025 15:52:24 +0200 Vlastimil Babka wrote: >>> @@ -5497,7 +5528,7 @@ int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp, >>> >>> if (likely(sheaf->capacity >= size)) { >>> if (likely(sheaf->capacity == s->sheaf_capacity)) >>> - return refill_sheaf(s, sheaf, gfp); >>> + return __prefill_sheaf_pfmemalloc(s, sheaf, gfp); >>> >>> if (!__kmem_cache_alloc_bulk(s, gfp, sheaf->capacity - sheaf->size, >>> &sheaf->objects[sheaf->size])) { >> ^^^ >> >> In kmem_cache_refill_sheaf(), does the oversize sheaf path (when >> sheaf->capacity != s->sheaf_capacity) need __GFP_NOMEMALLOC too? >> >> The commit message says "When refilling sheaves, use __GFP_NOMEMALLOC >> to override any pfmemalloc context", and the normal capacity path now >> calls __prefill_sheaf_pfmemalloc() which adds __GFP_NOMEMALLOC. >> >> But this oversize path still calls __kmem_cache_alloc_bulk() with the >> raw gfp flags. If the calling context is pfmemalloc-enabled (e.g., >> during swap or network operations), could pfmemalloc objects be >> allocated into the sheaf? Those objects would then be returned via > > Yes. > >> kmem_cache_alloc_from_sheaf() to potentially non-pfmemalloc callers. > > The assumption is the caller will use the prefilled sheaf for its purposes > and not pass it to other callers. The reason for caring about pfmemalloc and > setting sheaf->pfmemalloc is only to recognize them when the prefilled sheaf > is returned - so that it's flushed+freed and not attached as pcs->spare - > that would then be available to other non-pfmemalloc callers. > > But we always flush oversize sheaves when those are returned, so it's not > necessary to also track pfmemalloc for them. I'll add a comment about it. Oh I see, this makes sense. Thanks! -chris