From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from CY3PR05CU001.outbound.protection.outlook.com (mail-westcentralusazon11013058.outbound.protection.outlook.com [40.93.201.58]) (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 7B2F63C9ED0; Thu, 30 Apr 2026 23:26:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.93.201.58 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777591580; cv=fail; b=XVTANDvO7IfsMuyrT+8You2vY1HpMY9m+SsVDouGO3YjcJ2JpAA6VgzXES9YlmQS6IFOucO2eCXAooi2q2lYKTRWgabne/Bes2OVXnQofYR9P/iCmWagGMty+4hHwiNWBQBEOaXPQXqkAdsouNrogUBYLQx6VD0NhakWVyVpfkI= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777591580; c=relaxed/simple; bh=bSoUgZ098PNxTQofRZp6F1LQnAKWrK+fuCqJp3SCRZ0=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=fGgODaNHA7uY4GBpbsH8kaD4rhSL+AiXqiSOdVawdY/+UN/FaTe9HKsRaVIdPmlSanTny5HI9DjkocgOUCO9lySK4rVRb953N+ICAAV1caaae9qJTzKDTRu4/7twVdcIevVykHlfi2HiDorpj/OGPkOevx0GNanOdhn3QbxB2LQ= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=mUgFVv8D; arc=fail smtp.client-ip=40.93.201.58 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="mUgFVv8D" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=RywbYPhbmRRDlgNgg/gC8l1Q7oH1Oc0aGJbG780PfACUN/EqPolrwSZOmTrTX39YJMmFZExmoZKIKkC2jei4hMH1lbfFu5e738wxFu3zLunXIRErcUjWp0Lw32MzPfAJfc/gicIGkVW2aZk2RYOMMoAHYt4huWWaZDUZhJzIzaBMYPpRxPdXXh4zyOaGRWYv7dpwTgNDVkSRk4N131dDgq09hiQcy/HIs/H5gnt3uSBhm564VeZFIMcd4xdUavfPSQfmiXsg6S3V0bPWyxSM+RDSdDwOpj56zNmxxro9O6d03DlrY1d0Da7aFOlr/YNZWDOC/FkiDpq8F319GHst9A== 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=AVGMM5t4fS15YuQmxzd267AwJX0SSYcKCeBPlcpUmto=; b=nB5KaQktIPrRS74kXyEQ5ZE5RpzdxCNzR/soyMnye1DgJOdzFsFRA+fMvRZbzm83uSZw6+ri/CQ305Tg+gKcnP5feg4Ae7f6FHZDOH3hp/8iHnRvYdel99zdT5XRoq4vpJzjZVhl8UOOT8fYopFBnGsUeuF2YUqrxEv4rn4qWa0zTXIV9V17JnWuC2P7FhZKmo9PwQXHXTPad5aridgP1cba/etb/KapLOPXj56hNxQB0uh00KUw3gGJ+CQI10pduQPAJ8I6kIRoemEUM73XNOgqXAXd8rNDOEflAk4ZNrDMkn3tRel/GA8NkI+T5crslt727iwWTZTVKCKoBtwbEg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=lwn.net smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=AVGMM5t4fS15YuQmxzd267AwJX0SSYcKCeBPlcpUmto=; b=mUgFVv8DEGK+fgOyFxojhDAi/BIQHVh8w3DBLE95dP2yNSRcS3YCbBAftyQkoqY09SE1SwU2zODj8lHfo6cu0EuDn3vTyHXLoHW46h0Eex+r9piX9XDNm/UbgwHeS1DPPdOHoL2n3Dw/R8iSq6mb85CpnwH0vVWTZoxIGG/qUVM= Received: from SA0PR11CA0124.namprd11.prod.outlook.com (2603:10b6:806:131::9) by BY5PR12MB4050.namprd12.prod.outlook.com (2603:10b6:a03:207::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9870.20; Thu, 30 Apr 2026 23:26:13 +0000 Received: from SA2PEPF00001508.namprd04.prod.outlook.com (2603:10b6:806:131:cafe::f8) by SA0PR11CA0124.outlook.office365.com (2603:10b6:806:131::9) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9846.31 via Frontend Transport; Thu, 30 Apr 2026 23:26:13 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by SA2PEPF00001508.mail.protection.outlook.com (10.167.242.40) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9870.22 via Frontend Transport; Thu, 30 Apr 2026 23:26:13 +0000 Received: from bmoger-ubuntu.amd.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Thu, 30 Apr 2026 18:26:11 -0500 From: Babu Moger To: , , , , , , , CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v3 07/12] fs/resctrl: Add info/kernel_mode for kernel-mode policy introspection Date: Thu, 30 Apr 2026 18:24:52 -0500 Message-ID: <549bf0fadf1cedb5938599be58e53b7464c939b5.1777591497.git.babu.moger@amd.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: satlexmb07.amd.com (10.181.42.216) To satlexmb07.amd.com (10.181.42.216) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA2PEPF00001508:EE_|BY5PR12MB4050:EE_ X-MS-Office365-Filtering-Correlation-Id: 4c2eec4c-fb5b-4e34-c239-08dea70fde83 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|1800799024|36860700016|7416014|376014|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:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(82310400026)(1800799024)(36860700016)(7416014)(376014)(18002099003)(22082099003)(56012099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 37UNPuGp53pGXh/sQtc9QCAfbmM2MH0cRz78sScKlYAFKRZAC2a1AFKoRg0f9z65x69p4umBwPw+CnioYcQC5eEW+nF8vPNsZIhsnWAbpiNhRZdL9WGM0aP623N81Hi7Lc1DQCKJrYem9f99kheGPqqbEQVvZ1IhVzJxB4f8tTYYFB9NxN3PvY4I1ZZld6HJm0PRgBhY1yXaycdGLNM8jZxc/ZR3A14ioeVTRiX8tQgeN/mwqvneKiPL7kZVXGj/MQdIb5nLuUSR7g0y+sDg/EC606SsEI4HHCGU8yBsBPVsmRU1T4GOHQDM0qn9yPVMV0c+NfdTZ7k4sIZKOjFlk5IkGiA2sdfitOlhcpst1UW90oG5QPGvPnNocGK20IOeioJLGTZJNhGwrd9K19OJWZTg6R8g18a7V/FnG1dVF59tn5vpXnIKsBgA/AN1UNYP X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Apr 2026 23:26:13.2052 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 4c2eec4c-fb5b-4e34-c239-08dea70fde83 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=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SA2PEPF00001508.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4050 There is no user-visible way today to see which kernel-mode CLOSID/RMID policies the running kernel supports, which one is active, or which resctrl group currently owns the kernel CLOSID/RMID. Add a read-only top-level sysfs file, info/kernel_mode. It emits one line per mode advertised in resctrl_kcfg.kmode, in stable lowercase spelling derived from enum resctrl_kernel_modes, e.g.: [inherit_ctrl_and_mon:group=//] global_assign_ctrl_inherit_mon_per_cpu:group=none global_assign_ctrl_assign_mon_per_cpu:group=none The effective policy (resctrl_kcfg.kmode_cur) is wrapped in square brackets and its :group= suffix names the resctrl group currently bound to the kernel CLOSID/RMID (resctrl_kcfg.k_rdtgrp), formatted as // with empty components left blank. Inactive modes are reported as :group=none. rdtgroup_mutex is held while printing, matching other info/ show paths. Signed-off-by: Babu Moger --- v3: New patch to handle the changed interface file info/kernel_mode. Changed the group name to "none" if kmode binding is not done. Reinette suggested "uninitialized". "none" seemed more relevent. --- fs/resctrl/rdtgroup.c | 74 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c index a7bfc74897cc..9cdcfa64c4a2 100644 --- a/fs/resctrl/rdtgroup.c +++ b/fs/resctrl/rdtgroup.c @@ -988,6 +988,73 @@ static int rdt_last_cmd_status_show(struct kernfs_open_file *of, return 0; } +/* Sysfs lines for info/kernel_mode; indexed by &enum resctrl_kernel_modes */ +static const char * const resctrl_mode_str[] = { + [INHERIT_CTRL_AND_MON] = "inherit_ctrl_and_mon", + [GLOBAL_ASSIGN_CTRL_INHERIT_MON_PER_CPU] = "global_assign_ctrl_inherit_mon_per_cpu", + [GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU] = "global_assign_ctrl_assign_mon_per_cpu", +}; + +static_assert(ARRAY_SIZE(resctrl_mode_str) == RESCTRL_NUM_KERNEL_MODES); + +/** + * resctrl_kernel_mode_show() - Enumerate supported and effective kernel-mode policies + * @of: kernfs open file + * @seq: output seq_file + * @v: unused + * + * Emits one line per mode advertised in resctrl_kcfg.kmode (each mode is one + * BIT(index) per &enum resctrl_kernel_modes). Every line carries a + * ":group=" suffix: + * + * - The effective policy (whose BIT matches resctrl_kcfg.kmode_cur) is + * wrapped in square brackets and is the resctrl group that + * currently owns the kernel CLOSID/RMID (resctrl_kcfg.k_rdtgrp), + * formatted as "//". A component is left empty when it + * does not apply: an RDTCTRL_GROUP emits "//", an RDTMON_GROUP + * under the default control group emits "//", and an RDTMON_GROUP + * under a named control group emits "//". + * + * - Other supported but inactive modes are emitted without brackets and + * is reported as "none". + * + * Context: Called under rdtgroup_mutex like other resctrl sysfs show paths. + */ +static int resctrl_kernel_mode_show(struct kernfs_open_file *of, + struct seq_file *seq, void *v) +{ + struct rdtgroup *rdtgrp; + const char *ctrl, *mon; + int i; + + mutex_lock(&rdtgroup_mutex); + for (i = 0; i < RESCTRL_NUM_KERNEL_MODES; i++) { + if (!(resctrl_kcfg.kmode & BIT(i))) + continue; + + if (resctrl_kcfg.kmode_cur != BIT(i)) { + seq_printf(seq, "%s:group=none\n", + resctrl_mode_str[i]); + continue; + } + + rdtgrp = resctrl_kcfg.k_rdtgrp; + ctrl = ""; + mon = ""; + if (rdtgrp->type == RDTMON_GROUP) { + if (rdtgrp->mon.parent != &rdtgroup_default) + ctrl = rdtgrp->mon.parent->kn->name; + mon = rdtgrp->kn->name; + } else { + ctrl = rdtgrp->kn->name; + } + seq_printf(seq, "[%s:group=%s/%s/]\n", + resctrl_mode_str[i], ctrl, mon); + } + mutex_unlock(&rdtgroup_mutex); + return 0; +} + void *rdt_kn_parent_priv(struct kernfs_node *kn) { /* @@ -1891,6 +1958,13 @@ static struct rftype res_common_files[] = { .seq_show = rdt_last_cmd_status_show, .fflags = RFTYPE_TOP_INFO, }, + { + .name = "kernel_mode", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = resctrl_kernel_mode_show, + .fflags = RFTYPE_TOP_INFO, + }, { .name = "mbm_assign_on_mkdir", .mode = 0644, -- 2.43.0