From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (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 527F25013CC for ; Mon, 28 Sep 2026 22:15:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790633729; cv=none; b=Jkl73UVp2/MJUjYshoMw8ZWIuLiBW8lGz5+y8Xuk1dsSotzVFg3bq+Dtwo4+8JoFcMO5g3i85VObGeRCkPtVGAajMCE4IeERp9WOAy5/iF5IMpGf5q1OPzkKuHTncwWlect8W8EUrn7bFiJ6VllhtBbagktAup5WqOG7NmLun+8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790633729; c=relaxed/simple; bh=k5h8jG51D1LCqCkTgG/UlLgltohB8PGNOuyQuSnwDBk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qj3qJwePrKpGPSB9Y3YAxHPKki/ZBPXpw9N3MA1hrSSqh1tDoYdFk6M08LwOOxUJ+COUET4//5oq5P3YqEJIKqSBHdy8GwzRL8esmRj3IPgksapr36TUspcyz+K390fX+r2vb/OlQ0axz0cG3bxRNSrCdYZxUNqKn7lipuZc+zk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=PGg8LC+G; arc=none smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="PGg8LC+G" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790633726; x=1822169726; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=k5h8jG51D1LCqCkTgG/UlLgltohB8PGNOuyQuSnwDBk=; b=PGg8LC+GUWIoGu/+k2jJVW2qY0DvSK1yIlQk0E5JX94o8XuFiJ3YASXM XP6nppaXr8pKRA1kOcE0/3WCPEYrxmjr77MkvFyvDmc820E34q7c9xL8D SJbagsqRfKW1GTZd0v5mjA2r5slHZfZeRZfxfL2mFD4BE/lJjTs+PkiaX m7Nuim5R5yRfI5rxC93imX6+Y4y8OREifNtul7OZcS6HSExEiRfBqty5E D5u8cSYbSfGKxadrkAM845QMrYfXRwwcHEVgKYRzGtSvBxZzX8LTt4iCQ JC2omzfq8WB/uZ+tEtfNyQmc2fTwPdtpfzXJOzOytZOgCjaQtc7jGEKnU Q==; X-CSE-ConnectionGUID: uCpT7ZzRQJ6QqDCbOCKwRQ== X-CSE-MsgGUID: zFC/ZyHKR8KXbGCZxb778g== X-IronPort-AV: E=McAfee;i="6800,10657,11919"; a="90387197" X-IronPort-AV: E=Sophos;i="6.27,129,1787036400"; d="scan'208";a="90387197" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Sep 2026 15:15:18 -0700 X-CSE-ConnectionGUID: u5h8xWo5Td+aMB6lJ4SKng== X-CSE-MsgGUID: Fx8uazNhThi0nRYGxuprbw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,129,1787036400"; d="scan'208";a="274685475" Received: from lstrano-mobl6.amr.corp.intel.com (HELO agluck-desk3.intel.com) ([10.124.222.143]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Sep 2026 15:15:17 -0700 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Maciej Wieczor-Retman , Peter Newman , James Morse , Babu Moger , Drew Fustini , Dave Martin , Chen Yu , David E Box , x86@kernel.org Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH v13 05/25] x86/resctrl: Apply Intel MBM quirk from rdt_get_l3_mon_config() Date: Mon, 28 Sep 2026 15:14:49 -0700 Message-ID: <20260928221509.68002-6-tony.luck@intel.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260928221509.68002-1-tony.luck@intel.com> References: <20260928221509.68002-1-tony.luck@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The Intel quirk to adjust Memory Bandwidth Monitoring (MBM) values on certain CPUs is applied early, before discovering if MBM is supported. Move the call into rdt_get_l3_mon_config(), but keep the decision on whether it is needed in __check_quirks_intel() with all the other model specific tests. Signed-off-by: Tony Luck --- v13: Babu: s/intel_rdt_mbm_apply_quirk(r->mon.num_rmid)/intel_rdt_mbm_apply_quirk(num_rmid)/ Reinette: Add comment to code describing model specific details of quirk. --- arch/x86/kernel/cpu/resctrl/internal.h | 4 +-- arch/x86/kernel/cpu/resctrl/core.c | 2 +- arch/x86/kernel/cpu/resctrl/monitor.c | 40 ++++++++++++++++---------- 3 files changed, 28 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index e3cfa0c10e92..086282a82fca 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -151,6 +151,8 @@ static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r extern struct rdt_hw_resource rdt_resources_all[]; +extern bool intel_rdt_mbm_need_quirk; + void arch_mon_domain_online(struct rdt_resource *r, struct rdt_l3_mon_domain *d); /* CPUID.(EAX=10H, ECX=ResID=1).EAX */ @@ -228,8 +230,6 @@ int rdt_get_l3_mon_config(struct rdt_resource *r); bool rdt_cpu_has(int flag); -void __init intel_rdt_mbm_apply_quirk(void); - void rdt_domain_reconfigure_cdp(struct rdt_resource *r); void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r); diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 34ca3c7cc046..82b27a0157ae 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -1011,7 +1011,7 @@ static __init void __check_quirks_intel(void) set_rdt_options("!l3cat"); fallthrough; case INTEL_BROADWELL_X: - intel_rdt_mbm_apply_quirk(); + intel_rdt_mbm_need_quirk = true; break; } } diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c index 89b83cc7e800..468e9821f35a 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -37,6 +37,8 @@ bool rdt_mon_capable; */ unsigned int __ro_after_init rdt_l3_mon_scale; +bool __initdata intel_rdt_mbm_need_quirk; + #define CF(cf) ((unsigned long)(1048576 * (cf) + 0.5)) static int snc_nodes_per_l3_cache = 1; @@ -51,7 +53,7 @@ static int snc_nodes_per_l3_cache = 1; * 1. The threshold 0 is changed to rmid count - 1 so don't do correction * for the case. * 2. MBM total and local correction table indexed by core counter which is - * equal to (x86_cache_max_rmid + 1) / 8 - 1 and is from 0 up to 27. + * equal to num_rmid / 8 - 1 and is from 0 up to 27. * 3. The correction factor is normalized to 2^20 (1048576) so it's faster * to calculate corrected value by shifting: * corrected_value = (original_value * correction_factor) >> 20 @@ -421,6 +423,20 @@ static __init int snc_get_config(void) return ret; } +static void __init intel_rdt_mbm_apply_quirk(u32 num_rmid) +{ + unsigned int cf_index; + + cf_index = num_rmid / 8 - 1; + if (cf_index >= ARRAY_SIZE(mbm_cf_table)) { + pr_info("No MBM correction factor available\n"); + return; + } + + mbm_cf_rmidthreshold = mbm_cf_table[cf_index].rmidthreshold; + mbm_cf = mbm_cf_table[cf_index].cf; +} + int __init rdt_get_l3_mon_config(struct rdt_resource *r) { struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r); @@ -500,25 +516,19 @@ int __init rdt_get_l3_mon_config(struct rdt_resource *r) hw_res->mbm_cntr_assign_enabled = true; } + /* + * This quirk only applies to Intel Skylake and Broadwell + * CPUs. These don't support Sub-NUMA Cluster. Pass the + * raw number of RMIDs enumerated by CPUID(0xF,0x1).ECX. + */ + if (intel_rdt_mbm_need_quirk) + intel_rdt_mbm_apply_quirk(num_rmid); + r->mon_capable = true; return 0; } -void __init intel_rdt_mbm_apply_quirk(void) -{ - int cf_index; - - cf_index = (boot_cpu_data.x86_cache_max_rmid + 1) / 8 - 1; - if (cf_index >= ARRAY_SIZE(mbm_cf_table)) { - pr_info("No MBM correction factor available\n"); - return; - } - - mbm_cf_rmidthreshold = mbm_cf_table[cf_index].rmidthreshold; - mbm_cf = mbm_cf_table[cf_index].cf; -} - static void resctrl_abmc_set_one_amd(void *arg) { bool *enable = arg; -- 2.55.0