From nobody Sun Feb 8 14:10:25 2026 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (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 D68483570A3 for ; Wed, 29 Oct 2025 16:21:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.12 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761754910; cv=none; b=iXivEbK1jbsTtQDZlnMy9+kCqtWWIrDxOx9JZU8EgJO7oAv+41d/5zCI2MdnUarEonyKFgfZYYgMOl2BbpHOFCEdMirpoN18miuxVjhPJSZvldA1YxTip9Bxs4Nf8QsvnwLXkSrDe93UezNjvWHJteelwm61OSFbvtitWn+wUhU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761754910; c=relaxed/simple; bh=JiFS0CexxBfh1T3Xu534A0j8kEAr954jKVs6ltTpUC4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rqh4JYRzSP9+jaUy2CtMIt29Kl1B5kaJ1fmskd6T1vdPAziwLJ0jU3NKaze6Tn9//lq8DKbw70CpHnF53l+rh7dARsRulb8fjAFuZrRS8/OqiP64nB2hMhZzpPXFBVTlIV+09EoeMpYBhjq/B8hq5UtxiYq13eojsXgaggTdu0U= 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=ACILWPv2; arc=none smtp.client-ip=198.175.65.12 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="ACILWPv2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1761754907; x=1793290907; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=JiFS0CexxBfh1T3Xu534A0j8kEAr954jKVs6ltTpUC4=; b=ACILWPv2bdmw6lRld74fMFdMwhZbDtkr0uG/qd6h6mpZN2myb53h6ox2 Zt7zwm5rcy3WMmv3aveTsJvY+cNRRtEBrCcOav0hACQ5xkKGkfSC46Ygj Oets4dHhm0R92dF+1r/sQp2dqKMg8gFRPSyfa081uvotvR6aPUJkgKVln qi2r9OCoYQxhlnQjzoHPF2WhxpVjqOhaKQDgmc8zXX3t0EHqysiSMUizQ QZWRVM8fALLCvYMaH4koJMrDGgGj2a/VyYNmWB7mmE7WKVvPbE8QYGAMA eQvdLVqxC4Ra1fQ0PtCpuUU4GcfZx3x6pBNr+GM9phjuycntK7Nhj0tGw Q==; X-CSE-ConnectionGUID: PqBMl812Qq+MYZm2zbICYw== X-CSE-MsgGUID: pRmmuaroSamCPBhF6oQwFg== X-IronPort-AV: E=McAfee;i="6800,10657,11597"; a="75331045" X-IronPort-AV: E=Sophos;i="6.19,264,1754982000"; d="scan'208";a="75331045" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Oct 2025 09:21:35 -0700 X-CSE-ConnectionGUID: Svxtl1g7Q1+oMS5l0fC99Q== X-CSE-MsgGUID: P2PXqnESQ/y3aUR7Zo7zlA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,264,1754982000"; d="scan'208";a="184901409" Received: from mgerlach-mobl1.amr.corp.intel.com (HELO agluck-desk3.home.arpa) ([10.124.223.146]) by orviesa006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Oct 2025 09:21:35 -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 v13 28/32] fs/resctrl: Move RMID initialization to first mount Date: Wed, 29 Oct 2025 09:21:11 -0700 Message-ID: <20251029162118.40604-29-tony.luck@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251029162118.40604-1-tony.luck@intel.com> References: <20251029162118.40604-1-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 needs 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 Reviewed-by: Reinette Chatre --- 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 9f5097a4be82..448f490ba344 100644 --- a/fs/resctrl/monitor.c +++ b/fs/resctrl/monitor.c @@ -890,20 +890,29 @@ 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]; @@ -916,30 +925,24 @@ 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 @@ -1815,7 +1818,8 @@ 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 @@ -1835,12 +1839,6 @@ 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", @@ -1887,6 +1885,4 @@ 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 15b2765898d6..17f5b986f210 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; @@ -4586,4 +4590,5 @@ void resctrl_exit(void) */ =20 resctrl_l3_mon_resource_exit(); + free_rmid_lru_list(); } --=20 2.51.0