From nobody Thu Jan 1 07:17:53 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F58BC07545 for ; Tue, 24 Oct 2023 18:16:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343705AbjJXSQM (ORCPT ); Tue, 24 Oct 2023 14:16:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232399AbjJXSQK (ORCPT ); Tue, 24 Oct 2023 14:16:10 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62913111; Tue, 24 Oct 2023 11:16:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698171368; x=1729707368; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=svJxEnxlJxMe9ykA9n2RRTqPvoiO12Rhjx+c7UZ7Qtc=; b=gewH5H9ihy2gCNJ9HyFVF7TAbx+K/QiMkUiPFKPLq4yq7o3p6iC3cfxS 1+Ye9JVnFZb8GKOPE8fQS6cs0vumIbpl4c1RETdXwabX1rMblyiWLyYmH uWFpGP/mqNi9NTJHsE4cpH9lJJqHm2L1YzyLNpzsNMLuUR62ACOgMyNdw vFs8KtKZy6RiOi9SwDAKUk8dqAkzsHnVXkOVI5fj/rs5mTVjTliIJVS0F bgsceP62o8vNu4teXnIsJ6dXcuXAFIawVTFLG7jGMJ5JGEkS254M8i/BG xgk0jVWGXOAnGRcJ+ummVixTeIPlOKs+xixJaZylHz34vXFwfEx4Wnx6P Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10873"; a="8684419" X-IronPort-AV: E=Sophos;i="6.03,248,1694761200"; d="scan'208";a="8684419" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2023 11:16:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10873"; a="1089950438" X-IronPort-AV: E=Sophos;i="6.03,248,1694761200"; d="scan'208";a="1089950438" Received: from agluck-desk3.sc.intel.com ([172.25.222.74]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2023 11:16:07 -0700 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Peter Newman , Jonathan Corbet , Shuah Khan , x86@kernel.org Cc: Shaopeng Tan , James Morse , Jamie Iles , Babu Moger , Randy Dunlap , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH] x86/resctrl: mba_MBps: Fall back to total b/w if local b/w unavailable Date: Tue, 24 Oct 2023 11:16:00 -0700 Message-ID: <20231024181600.8270-1-tony.luck@intel.com> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Intel the various resource director technology (RDT) features are all orthogonal and independently enumerated. Thus it is possible to have a system that provides "total" memory bandwidth measurements without providing "local" bandwidth measurements. If local bandwidth measurement is not available, do not give up on providing the "mba_MBps" feedback option completely, make the code fall back to using total bandwidth. Signed-off-by: Tony Luck Reviewed-by: Peter Newman --- arch/x86/kernel/cpu/resctrl/monitor.c | 34 ++++++++++++++++---------- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +- 2 files changed, 22 insertions(+), 14 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/re= sctrl/monitor.c index f136ac046851..3b9531cce807 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -418,6 +418,14 @@ static int __mon_event_count(u32 rmid, struct rmid_rea= d *rr) return 0; } =20 +static struct mbm_state *get_mbm_data(struct rdt_domain *dom_mbm, int rmid) +{ + if (is_mbm_local_enabled()) + return &dom_mbm->mbm_local[rmid]; + + return &dom_mbm->mbm_total[rmid]; +} + /* * mbm_bw_count() - Update bw count from values previously read by * __mon_event_count(). @@ -431,7 +439,7 @@ static int __mon_event_count(u32 rmid, struct rmid_read= *rr) */ static void mbm_bw_count(u32 rmid, struct rmid_read *rr) { - struct mbm_state *m =3D &rr->d->mbm_local[rmid]; + struct mbm_state *m =3D get_mbm_data(rr->d, rmid); u64 cur_bw, bytes, cur_bytes; =20 cur_bytes =3D rr->val; @@ -526,14 +534,14 @@ static void update_mba_bw(struct rdtgroup *rgrp, stru= ct rdt_domain *dom_mbm) struct list_head *head; struct rdtgroup *entry; =20 - if (!is_mbm_local_enabled()) + if (!is_mbm_enabled()) return; =20 r_mba =3D &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; =20 closid =3D rgrp->closid; rmid =3D rgrp->mon.rmid; - pmbm_data =3D &dom_mbm->mbm_local[rmid]; + pmbm_data =3D get_mbm_data(dom_mbm, rmid); =20 dom_mba =3D get_domain_from_cpu(smp_processor_id(), r_mba); if (!dom_mba) { @@ -553,7 +561,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct= rdt_domain *dom_mbm) */ head =3D &rgrp->mon.crdtgrp_list; list_for_each_entry(entry, head, mon.crdtgrp_list) { - cmbm_data =3D &dom_mbm->mbm_local[entry->mon.rmid]; + cmbm_data =3D get_mbm_data(dom_mbm, entry->mon.rmid); cur_bw +=3D cmbm_data->prev_bw; delta_bw +=3D cmbm_data->delta_bw; } @@ -595,7 +603,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct= rdt_domain *dom_mbm) */ pmbm_data->delta_comp =3D true; list_for_each_entry(entry, head, mon.crdtgrp_list) { - cmbm_data =3D &dom_mbm->mbm_local[entry->mon.rmid]; + cmbm_data =3D get_mbm_data(dom_mbm, entry->mon.rmid); cmbm_data->delta_comp =3D true; } } @@ -621,15 +629,15 @@ static void mbm_update(struct rdt_resource *r, struct= rdt_domain *d, int rmid) rr.evtid =3D QOS_L3_MBM_LOCAL_EVENT_ID; rr.val =3D 0; __mon_event_count(rmid, &rr); - - /* - * Call the MBA software controller only for the - * control groups and when user has enabled - * the software controller explicitly. - */ - if (is_mba_sc(NULL)) - mbm_bw_count(rmid, &rr); } + + /* + * Call the MBA software controller only for the + * control groups and when user has enabled + * the software controller explicitly. + */ + if (is_mba_sc(NULL)) + mbm_bw_count(rmid, &rr); } =20 /* diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r= esctrl/rdtgroup.c index 69a1de92384a..0c4f8a1b8df0 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -2294,7 +2294,7 @@ static bool supports_mba_mbps(void) { struct rdt_resource *r =3D &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; =20 - return (is_mbm_local_enabled() && + return (is_mbm_enabled() && r->alloc_capable && is_mba_linear()); } =20 --=20 2.41.0