From nobody Fri Dec 19 03:45:32 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 792B933A01C for ; Wed, 17 Dec 2025 17:22:26 +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=1765992156; cv=none; b=EejKH4+Rf/9RCO3tMrTw6AcZxuKCcpdnQBR0sWsLs6p/46bUWv8PiNSDu8eXW4k7fpOgYXxq7N+ji6C2r4PhihIvUOl5qFTbcLguG62tBuhGGoDwrznglSI0ZXqgQjNH080aHvWUVboD9zO77tnMVl4ljfu2rXGDOOOT1NxdVjw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765992156; c=relaxed/simple; bh=ZGkLRQwYF8TMTMAKGpM6HE3+MCT0STxYa/rFAM+2v+4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pY087RP+0Hi3EGC+MASHIReQ2PWAPDgZMu6b9moa1SaWfCWuwSlhiW0V5cLtb4ibNL4jZNfymCqpn5Ye7MJb3C5VwZocjKdZNdxc0/JrVsXm4gKRNXgF54Df+4QGVEwHhtFIP0sfb0MrQXGIt3dHXL0tXPWhhoHdFLoT6xTYfFE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=fail smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=mWjTn81m; 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=fail 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="mWjTn81m" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1765992148; x=1797528148; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZGkLRQwYF8TMTMAKGpM6HE3+MCT0STxYa/rFAM+2v+4=; b=mWjTn81mC45SobiyLKN8XosZi7awpHgxDugYUA4x4dlaLpucFzB7nonF 4xCyuGCHTjEm091r0ZZblR72e2Ace/aK8qChgtArkV6gKw+7sbs+CAsCg 8ovkvpjsH0ENCmVDg1B6X55Iq1tdLYFrewYcFB1tSub0qmpdiMuznl76B wpuRk+RWoemaOJPUcujZ4pz4hzciydElYE0L+czikasSgctxCt5O3AUxc FKhN8roVXs5h/t6F7YjBEuexj96Zz5zku8W5b4BUely6XfBtRAj9Uspq2 M3o75NWPpnLKhn3xBNO3NPmkdhY8J+QtD6m71eFbfzwZ8YPL2OchSDbDD g==; X-CSE-ConnectionGUID: jwqUUw4UQGmQZ+2l+pnjKg== X-CSE-MsgGUID: wtUxSyZxRv6mu8GaOHmwHg== X-IronPort-AV: E=McAfee;i="6800,10657,11645"; a="90594856" X-IronPort-AV: E=Sophos;i="6.21,156,1763452800"; d="scan'208";a="90594856" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Dec 2025 09:21:38 -0800 X-CSE-ConnectionGUID: iFECk9HwSPqNAD2ZX2+f1Q== X-CSE-MsgGUID: Snd42GXVS9aZqExVM9X2mw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,156,1763452800"; d="scan'208";a="221748268" Received: from pgcooper-mobl3.ger.corp.intel.com (HELO agluck-desk3.home.arpa) ([10.124.223.131]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Dec 2025 09:21:37 -0800 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 v17 28/32] fs/resctrl: Move RMID initialization to first mount Date: Wed, 17 Dec 2025 09:21:15 -0800 Message-ID: <20251217172121.12030-29-tony.luck@intel.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251217172121.12030-1-tony.luck@intel.com> References: <20251217172121.12030-1-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 399f625be67d..1a9b29119f88 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 bbf8c9037887..0cd5476a483a 100644 --- a/fs/resctrl/monitor.c +++ b/fs/resctrl/monitor.c @@ -903,20 +903,29 @@ 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]; @@ -929,30 +938,24 @@ 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", @@ -1902,6 +1900,4 @@ 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 e95d3d0dc515..d49ffc56ea61 100644 --- a/fs/resctrl/rdtgroup.c +++ b/fs/resctrl/rdtgroup.c @@ -2799,6 +2799,10 @@ 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; @@ -4654,4 +4658,5 @@ void resctrl_exit(void) */ =20 resctrl_l3_mon_resource_exit(); + free_rmid_lru_list(); } --=20 2.52.0