From nobody Thu Apr 2 14:47:32 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 044A8C001B5 for ; Fri, 2 Sep 2022 15:57:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237750AbiIBP5X (ORCPT ); Fri, 2 Sep 2022 11:57:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237502AbiIBPzl (ORCPT ); Fri, 2 Sep 2022 11:55:41 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8060815A0E for ; Fri, 2 Sep 2022 08:49:36 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5A86415A1; Fri, 2 Sep 2022 08:49:42 -0700 (PDT) Received: from merodach.members.linode.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C97783F766; Fri, 2 Sep 2022 08:49:33 -0700 (PDT) From: James Morse To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Fenghua Yu , Reinette Chatre , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , James Morse , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, Jamie Iles , Cristian Marussi , Xin Hao , xingxin.hx@openanolis.org, baolin.wang@linux.alibaba.com Subject: [PATCH v6 16/21] x86/resctrl: Pass the required parameters into resctrl_arch_rmid_read() Date: Fri, 2 Sep 2022 15:48:24 +0000 Message-Id: <20220902154829.30399-17-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220902154829.30399-1-james.morse@arm.com> References: <20220902154829.30399-1-james.morse@arm.com> 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" resctrl_arch_rmid_read() is intended as the function that an architecture agnostic resctrl filesystem driver can use to read a value in bytes from a hardware register. Currently the function returns the MBM values in chunks directly from hardware. To convert this to bytes, some correction and overflow calculations are needed. These depend on the resource and domain structures. Overflow detection requires the old chunks value. None of this is available to resctrl_arch_rmid_read(). MPAM requires the resource and domain structures to find the MMIO device that holds the registers. Pass the resource and domain to resctrl_arch_rmid_read(). This makes rmid_dirty() too big. Instead merge it with its only caller, and the name is kept as a local variable. Reviewed-by: Jamie Iles Tested-by: Xin Hao Reviewed-by: Shaopeng Tan Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Reviewed-by: Reinette Chatre Signed-off-by: James Morse --- Changes since v3: * Added comment about where resctrl_arch_rmid_read() can be called from. Changes since v2: * Typos. * Kerneldoc fixes. This is all a little noisy for __mon_event_count(), as the switch statement work is now before the resctrl_arch_rmid_read() call. --- arch/x86/kernel/cpu/resctrl/monitor.c | 31 +++++++++++++++------------ include/linux/resctrl.h | 18 +++++++++++++++- 2 files changed, 34 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/re= sctrl/monitor.c index 51ab76f2dfbc..262141bf4264 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -167,10 +167,14 @@ void resctrl_arch_reset_rmid(struct rdt_resource *r, = struct rdt_domain *d, memset(am, 0, sizeof(*am)); } =20 -int resctrl_arch_rmid_read(u32 rmid, enum resctrl_event_id eventid, u64 *v= al) +int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d, + u32 rmid, enum resctrl_event_id eventid, u64 *val) { u64 msr_val; =20 + if (!cpumask_test_cpu(smp_processor_id(), &d->cpu_mask)) + return -EINVAL; + /* * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured * with a valid event code for supported resource type and the bits @@ -192,16 +196,6 @@ int resctrl_arch_rmid_read(u32 rmid, enum resctrl_even= t_id eventid, u64 *val) return 0; } =20 -static bool rmid_dirty(struct rmid_entry *entry) -{ - u64 val =3D 0; - - if (resctrl_arch_rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID, &val)) - return true; - - return val >=3D resctrl_cqm_threshold; -} - /* * Check the RMIDs that are marked as busy for this domain. If the * reported LLC occupancy is below the threshold clear the busy bit and @@ -213,6 +207,8 @@ void __check_limbo(struct rdt_domain *d, bool force_fre= e) struct rmid_entry *entry; struct rdt_resource *r; u32 crmid =3D 1, nrmid; + bool rmid_dirty; + u64 val =3D 0; =20 r =3D &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; =20 @@ -228,7 +224,14 @@ void __check_limbo(struct rdt_domain *d, bool force_fr= ee) break; =20 entry =3D __rmid_entry(nrmid); - if (force_free || !rmid_dirty(entry)) { + + if (resctrl_arch_rmid_read(r, d, entry->rmid, + QOS_L3_OCCUP_EVENT_ID, &val)) + rmid_dirty =3D true; + else + rmid_dirty =3D (val >=3D resctrl_cqm_threshold); + + if (force_free || !rmid_dirty) { clear_bit(entry->rmid, d->rmid_busy_llc); if (!--entry->busy) { rmid_limbo_count--; @@ -278,7 +281,7 @@ static void add_rmid_to_limbo(struct rmid_entry *entry) cpu =3D get_cpu(); list_for_each_entry(d, &r->domains, list) { if (cpumask_test_cpu(cpu, &d->cpu_mask)) { - err =3D resctrl_arch_rmid_read(entry->rmid, + err =3D resctrl_arch_rmid_read(r, d, entry->rmid, QOS_L3_OCCUP_EVENT_ID, &val); if (err || val <=3D resctrl_cqm_threshold) @@ -336,7 +339,7 @@ static int __mon_event_count(u32 rmid, struct rmid_read= *rr) if (rr->first) resctrl_arch_reset_rmid(rr->r, rr->d, rmid, rr->evtid); =20 - rr->err =3D resctrl_arch_rmid_read(rmid, rr->evtid, &tval); + rr->err =3D resctrl_arch_rmid_read(rr->r, rr->d, rmid, rr->evtid, &tval); if (rr->err) return rr->err; =20 diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index efe60dd7fd21..7ccfa0d1bb34 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -219,7 +219,23 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, st= ruct rdt_domain *d, u32 closid, enum resctrl_conf_type type); int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d); void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d); -int resctrl_arch_rmid_read(u32 rmid, enum resctrl_event_id eventid, u64 *r= es); + +/** + * resctrl_arch_rmid_read() - Read the eventid counter corresponding to rm= id + * for this resource and domain. + * @r: resource that the counter should be read from. + * @d: domain that the counter should be read from. + * @rmid: rmid of the counter to read. + * @eventid: eventid to read, e.g. L3 occupancy. + * @val: result of the counter read in chunks. + * + * Call from process context on a CPU that belongs to domain @d. + * + * Return: + * 0 on success, or -EIO, -EINVAL etc on error. + */ +int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d, + u32 rmid, enum resctrl_event_id eventid, u64 *val); =20 /** * resctrl_arch_reset_rmid() - Reset any private state associated with rmid --=20 2.30.2