From nobody Fri Dec 19 19:01:30 2025 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 BC2E330E84E for ; Mon, 13 Oct 2025 22:34:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760394861; cv=none; b=lNWQcQiWbgrPqBoGEBnXfKpZz/q4eVexyWbxBql9NPaJgooveCfTNGspEeYiklKIKF+fxwcTPePSsnlqIZDZVLkYcT7J8cX239C5Xuc0JX6/AUM3b+tvCa7T8fqqzACwwZLDSDEAcxTcCHoVhMGGtR2OELGkHmalHnE9GdBNlho= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760394861; c=relaxed/simple; bh=30XH7Z/Zz5NjCV5G3ZhrejvVkWxbn154b/BrJEoERCk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WcdJzmXBC/Ki6CJRrIURM0MBzLC+q5v1mRpP0MUTSko+V9P6wVz19VdN8PkZzUBjERB2H9MOenhxvqfjsqk/NfGUDnhKdq04ZBj8Htkv4VmoFe1Pykb45goRiyu2WGd3i8igSNhx91sqss3q25OOGWoGz8F0znMHyTQJmpwXoks= 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=P0+Rb6at; arc=none smtp.client-ip=198.175.65.9 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="P0+Rb6at" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760394859; x=1791930859; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=30XH7Z/Zz5NjCV5G3ZhrejvVkWxbn154b/BrJEoERCk=; b=P0+Rb6ateC0t3aSIpEwJsjnEUqKERrJF/4BqVU9mQ3YAPNI4yI74S8Oc +ttZH5uVvft8H9fVvjA/TePCUTC419goop1lNeMK4NB9qXUCblVGw5mVY Sf2Th13IikNaHgURGPioZSMbmWVUMk10c/hW26lrz5yC7ccL6JLgfk+A+ 1BezkdooYvNjf/sznAxrnDnybij4KeOqPtSsF2XTafNq5inMMvJ3E/JNU TpqNeZIPYgCpCUANlKCV3waRviGogVWoCSG33pFlWvVbD5bSjnbE6SkqI ua3cOsF3twQhjVc5MzHOWrAeFuy2pqBBKDyC/LREjr9HGIY+o7zVxwAwq g==; X-CSE-ConnectionGUID: jOIan8LvRFWeELXwmu57TA== X-CSE-MsgGUID: LCUyCXCaRjWsuic826j70w== X-IronPort-AV: E=McAfee;i="6800,10657,11581"; a="85168947" X-IronPort-AV: E=Sophos;i="6.19,226,1754982000"; d="scan'208";a="85168947" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2025 15:34:04 -0700 X-CSE-ConnectionGUID: WP2MIzcmQfCtz2t+YAFWdg== X-CSE-MsgGUID: qIhNLSXEQvO4djOJNlYLZw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,226,1754982000"; d="scan'208";a="182145335" Received: from sramkris-mobl1.amr.corp.intel.com (HELO agluck-desk3.intel.com) ([10.124.222.79]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2025 15:34:03 -0700 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Maciej Wieczor-Retman , Peter Newman , James Morse , Babu Moger , Drew Fustini , Dave Martin , Chen Yu Cc: x86@kernel.org, linux-kernel@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH v12 27/31] fs/resctrl: Move RMID initialization to first mount Date: Mon, 13 Oct 2025 15:33:41 -0700 Message-ID: <20251013223348.103390-28-tony.luck@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251013223348.103390-1-tony.luck@intel.com> References: <20251013223348.103390-1-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: quoted-printable Content-Type: text/plain; charset="utf-8" L3 monitor features are enumerated during resctrl initialization and rmid_ptrs[] that tracks all RMIDs and depends on the number of supported RMIDs is allocated during this time. Telemetry monitor features are enumerated during first resctrl mount and may support a different number of RMIDs compared to L3 monitor features. Delay allocation and initialization of rmid_ptrs[] until first mount. Since the number of RMIDs cannot change on later mounts, keep the same set of rmid_ptrs[] until resctrl_exit(). This is required because the limbo handler keeps running after resctrl is unmounted and may likely need to access rmid_ptrs[] as it keeps tracking busy RMIDs after unmount. Rename routines to match what they now do: dom_data_init() -> setup_rmid_lru_list() dom_data_exit() -> free_rmid_lru_list() Signed-off-by: Tony Luck --- fs/resctrl/internal.h | 4 ++++ fs/resctrl/monitor.c | 54 ++++++++++++++++++++----------------------- fs/resctrl/rdtgroup.c | 5 ++++ 3 files changed, 34 insertions(+), 29 deletions(-) diff --git a/fs/resctrl/internal.h b/fs/resctrl/internal.h index 46fd648a2961..0dd89d3fa31a 100644 --- a/fs/resctrl/internal.h +++ b/fs/resctrl/internal.h @@ -369,6 +369,10 @@ int closids_supported(void); =20 void closid_free(int closid); =20 +int setup_rmid_lru_list(void); + +void free_rmid_lru_list(void); + int alloc_rmid(u32 closid); =20 void free_rmid(u32 closid, u32 rmid); diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c index 2782e2e212f6..66157f650d10 100644 --- a/fs/resctrl/monitor.c +++ b/fs/resctrl/monitor.c @@ -907,20 +907,29 @@ void mbm_setup_overflow_handler(struct rdt_l3_mon_dom= ain *dom, unsigned long del schedule_delayed_work_on(cpu, &dom->mbm_over, delay); } =20 -static int dom_data_init(struct rdt_resource *r) +int setup_rmid_lru_list(void) { - u32 idx_limit =3D resctrl_arch_system_num_rmid_idx(); struct rmid_entry *entry =3D NULL; - int err =3D 0, i; + u32 idx_limit; u32 idx; + int i; =20 - mutex_lock(&rdtgroup_mutex); + if (!resctrl_arch_mon_capable()) + return 0; =20 + /* + * Called on every mount, but the number of RMIDs cannot change + * after the first mount, so keep using the same set of rmid_ptrs[] + * until resctrl_exit(). Note that the limbo handler continues to + * access rmid_ptrs[] after resctrl is unmounted. + */ + if (rmid_ptrs) + return 0; + + idx_limit =3D resctrl_arch_system_num_rmid_idx(); rmid_ptrs =3D kcalloc(idx_limit, sizeof(struct rmid_entry), GFP_KERNEL); - if (!rmid_ptrs) { - err =3D -ENOMEM; - goto out_unlock; - } + if (!rmid_ptrs) + return -ENOMEM; =20 for (i =3D 0; i < idx_limit; i++) { entry =3D &rmid_ptrs[i]; @@ -933,30 +942,24 @@ static int dom_data_init(struct rdt_resource *r) /* * RESCTRL_RESERVED_CLOSID and RESCTRL_RESERVED_RMID are special and * are always allocated. These are used for the rdtgroup_default - * control group, which will be setup later in resctrl_init(). + * control group, which was setup earlier in rdtgroup_setup_default(). */ idx =3D resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID, RESCTRL_RESERVED_RMID); entry =3D __rmid_entry(idx); list_del(&entry->list); =20 -out_unlock: - mutex_unlock(&rdtgroup_mutex); - - return err; + return 0; } =20 -static void dom_data_exit(struct rdt_resource *r) +void free_rmid_lru_list(void) { - mutex_lock(&rdtgroup_mutex); - - if (!r->mon_capable) - goto out_unlock; + if (!resctrl_arch_mon_capable()) + return; =20 + mutex_lock(&rdtgroup_mutex); kfree(rmid_ptrs); rmid_ptrs =3D NULL; - -out_unlock: mutex_unlock(&rdtgroup_mutex); } =20 @@ -1830,7 +1833,8 @@ static void closid_num_dirty_rmid_free(void) * resctrl_l3_mon_resource_init() - Initialise global monitoring structure= s. * * Allocate and initialise global monitor resources that do not belong to a - * specific domain. i.e. the rmid_ptrs[] used for the limbo and free lists. + * specific domain. i.e. the closid_num_dirty_rmid[] used to find the CLOS= ID + * with the cleanest set of RMIDs. * Called once during boot after the struct rdt_resource's have been confi= gured * but before the filesystem is mounted. * Resctrl's cpuhp callbacks may be called before this point to bring a do= main @@ -1850,12 +1854,6 @@ int resctrl_l3_mon_resource_init(void) if (ret) return ret; =20 - ret =3D dom_data_init(r); - if (ret) { - closid_num_dirty_rmid_free(); - return ret; - } - if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) { mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID].configurable =3D true; resctrl_file_fflags_init("mbm_total_bytes_config", @@ -1904,6 +1902,4 @@ void resctrl_l3_mon_resource_exit(void) return; =20 closid_num_dirty_rmid_free(); - - dom_data_exit(r); } diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c index c94536382316..c1c02b5bf5d7 100644 --- a/fs/resctrl/rdtgroup.c +++ b/fs/resctrl/rdtgroup.c @@ -2734,6 +2734,10 @@ static int rdt_get_tree(struct fs_context *fc) goto out; } =20 + ret =3D setup_rmid_lru_list(); + if (ret) + goto out; + ret =3D rdtgroup_setup_root(ctx); if (ret) goto out; @@ -4596,4 +4600,5 @@ void resctrl_exit(void) */ =20 resctrl_l3_mon_resource_exit(); + free_rmid_lru_list(); } --=20 2.51.0