From mboxrd@z Thu Jan 1 00:00:00 1970 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C823C433EF for ; Fri, 1 Oct 2021 16:04:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3091561AD1 for ; Fri, 1 Oct 2021 16:04:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355380AbhJAQGK (ORCPT ); Fri, 1 Oct 2021 12:06:10 -0400 Received: from foss.arm.com ([217.140.110.172]:46822 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1355334AbhJAQFz (ORCPT ); Fri, 1 Oct 2021 12:05:55 -0400 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 8B8A413D5; Fri, 1 Oct 2021 09:04:10 -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 8F2233F766; Fri, 1 Oct 2021 09:04:08 -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, Jamie Iles , D Scott Phillips OS , lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com Subject: [PATCH v2 17/23] x86/resctrl: Abstract __rmid_read() Date: Fri, 1 Oct 2021 16:02:56 +0000 Message-Id: <20211001160302.31189-18-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20211001160302.31189-1-james.morse@arm.com> References: <20211001160302.31189-1-james.morse@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __rmid_read() selects the specified eventid and returns the counter value from the msr. The error handling is architecture specific, and handled by the callers, rdtgroup_mondata_show() and __mon_event_count(). Error handling should be handled by architecture specific code, as a different architecture may have different requirements. MPAM's counters can report that they are 'not ready', requiring a second read after a short delay. This should be hidden from resctrl. Make __rmid_read() the architecture specific function for reading a counter. Rename it resctrl_arch_rmid_read() and move the error handling into it. Signed-off-by: James Morse --- Changes since v1: * Return EINVAL from the impossible case in __mon_event_count() instead of an x86 hardware specific value. --- arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 4 +-- arch/x86/kernel/cpu/resctrl/internal.h | 2 +- arch/x86/kernel/cpu/resctrl/monitor.c | 42 +++++++++++++++-------- include/linux/resctrl.h | 1 + 4 files changed, 31 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index 25baacd331e0..c8ca7184c6d9 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -579,9 +579,9 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg) mon_event_read(&rr, r, d, rdtgrp, evtid, false); - if (rr.val & RMID_VAL_ERROR) + if (rr.err == -EIO) seq_puts(m, "Error\n"); - else if (rr.val & RMID_VAL_UNAVAIL) + else if (rr.err == -EINVAL) seq_puts(m, "Unavailable\n"); else seq_printf(m, "%llu\n", rr.val * hw_res->mon_scale); diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index f3f31315a907..eca7793d3342 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -40,7 +40,6 @@ */ #define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE) - struct rdt_fs_context { struct kernfs_fs_context kfc; bool enable_cdpl2; @@ -94,6 +93,7 @@ struct rmid_read { struct rdt_domain *d; enum resctrl_event_id evtid; bool first; + int err; u64 val; }; diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c index 35eef49954b0..cf35eaf01042 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -167,9 +167,9 @@ void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_domain *d, memset(am, 0, sizeof(*am)); } -static u64 __rmid_read(u32 rmid, enum resctrl_event_id eventid) +int resctrl_arch_rmid_read(u32 rmid, enum resctrl_event_id eventid, u64 *val) { - u64 val; + u64 msr_val; /* * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured @@ -180,14 +180,24 @@ static u64 __rmid_read(u32 rmid, enum resctrl_event_id eventid) * are error bits. */ wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid); - rdmsrl(MSR_IA32_QM_CTR, val); + rdmsrl(MSR_IA32_QM_CTR, msr_val); - return val; + if (msr_val & RMID_VAL_ERROR) + return -EIO; + if (msr_val & RMID_VAL_UNAVAIL) + return -EINVAL; + + *val = msr_val; + + return 0; } static bool rmid_dirty(struct rmid_entry *entry) { - u64 val = __rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID); + u64 val = 0; + + if (resctrl_arch_rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID, &val)) + return true; return val >= resctrl_cqm_threshold; } @@ -259,8 +269,8 @@ static void add_rmid_to_limbo(struct rmid_entry *entry) { struct rdt_resource *r; struct rdt_domain *d; - int cpu; - u64 val; + int cpu, err; + u64 val = 0; r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; @@ -268,8 +278,10 @@ static void add_rmid_to_limbo(struct rmid_entry *entry) cpu = get_cpu(); list_for_each_entry(d, &r->domains, list) { if (cpumask_test_cpu(cpu, &d->cpu_mask)) { - val = __rmid_read(entry->rmid, QOS_L3_OCCUP_EVENT_ID); - if (val <= resctrl_cqm_threshold) + err = resctrl_arch_rmid_read(entry->rmid, + QOS_L3_OCCUP_EVENT_ID, + &val); + if (err || val <= resctrl_cqm_threshold) continue; } @@ -319,15 +331,15 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read *rr) { struct rdt_hw_resource *hw_res = resctrl_to_arch_res(rr->r); struct mbm_state *m; - u64 chunks, tval; + u64 chunks, tval = 0; if (rr->first) resctrl_arch_reset_rmid(rr->r, rr->d, rmid, rr->evtid); - tval = __rmid_read(rmid, rr->evtid); - if (tval & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL)) { - return tval; - } + rr->err = resctrl_arch_rmid_read(rmid, rr->evtid, &tval); + if (rr->err) + return rr->err; + switch (rr->evtid) { case QOS_L3_OCCUP_EVENT_ID: rr->val += tval; @@ -343,7 +355,7 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read *rr) * Code would never reach here because an invalid * event id would fail the __rmid_read. */ - return RMID_VAL_ERROR; + return -EINVAL; } if (rr->first) { diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index 04f30d80fc67..01bdd8be590b 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -218,6 +218,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct 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 *res); /** * resctrl_arch_reset_rmid() - Reset any private state associated with rmid -- 2.30.2