From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (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 41A51548FA for ; Thu, 22 Feb 2024 18:50:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708627849; cv=none; b=YnnwswESNoDf+wzWktOHN10piyhpLGPAymRZqD2bjzyz5PzuHOZ9IbdeGLm1+9ZsvL28UPLMjaqjeKyR/d/dhULa+3DXaudICcotgIKeVPFu1auO7DtDWIm8yRGmMug9XLxKwHZKa8t6MyCt/fhYfabjl5p6na+A8UDpQyFbx28= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708627849; c=relaxed/simple; bh=fRVotIdvOYh4V5LZe1qsMnlas+ZOCRdyKmV7eSRP8kk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RWzrKFKKuQed4GGsQLutPypuLJ7WcX6TU4heGL60VeTFh4NicPL8I01tVSGs+a+4v3QN3sWqNcz51uKd9Ed2OC5wRAetBwB2EXn5JZC0GbwAWVCmGe1+wLSkVdRwGe0T/d3cKlarwO5xu+RDg9baPP8+YScGAEc99iIC4Z/csIg= 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=NIXX28q3; arc=none smtp.client-ip=192.198.163.15 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="NIXX28q3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1708627847; x=1740163847; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fRVotIdvOYh4V5LZe1qsMnlas+ZOCRdyKmV7eSRP8kk=; b=NIXX28q3ekt7fAN+EpY6tV65xQ1tbxsjar/sN0ntiFrUA0NNzE1ZsbkR vvb2uMaYAF3+ZJO+hvgOJl/qvYnYUqSnCZZYYpnyxAcSGbxtFTy6mCUj2 LgAlNKrYKr6BZ8xRGnIWcZMtX2O+B2hwcqZtwmJbAKgR6NvG7CicFjyLV wj6ep1bTQaii8Wic8Im7jED+fJYegDbBovqAVDjgiGyftrhLkNko4LWrG mJujcYpPOkNhqaoIPYrBSeYIGRK/oz8lpc4hTOIrlidCQZxv54rcrgiSB WNHAS3wZszMXQbru74GWSSi0iBQ0oheXu+Ran2My/+3SchvtTD3QLSY9M w==; X-IronPort-AV: E=McAfee;i="6600,9927,10992"; a="3020551" X-IronPort-AV: E=Sophos;i="6.06,179,1705392000"; d="scan'208";a="3020551" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Feb 2024 10:50:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10992"; a="936889170" X-IronPort-AV: E=Sophos;i="6.06,179,1705392000"; d="scan'208";a="936889170" Received: from agluck-desk3.sc.intel.com ([172.25.222.74]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Feb 2024 10:50:45 -0800 From: Tony Luck To: "Chatre, Reinette" , Borislav Petkov , James Morse Cc: Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org, "Yu, Fenghua" , Ingo Molnar , H Peter Anvin , Babu Moger , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com, David Hildenbrand , Tony Luck Subject: [PATCH v3 1/2] x86/resctrl: Pass domain to target CPU Date: Thu, 22 Feb 2024 10:50:38 -0800 Message-ID: <20240222185039.72201-2-tony.luck@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240222185039.72201-1-tony.luck@intel.com> References: <20240222185039.72201-1-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: 8bit reset_all_ctrls() and resctrl_arch_update_domains() use on_each_cpu_mask() to call rdt_ctrl_update() on potentially one CPU from each domain. But this means rdt_ctrl_update() needs to figure out which domain to apply changes to. Doing so requires a search of all domains in a resource, which can only be done safely if cpus_lock is held. Both callers do hold this lock, but there isn't a way for a function called on another CPU via IPI to verify this. Commit c0d848fcb09d ("x86/resctrl: Remove lockdep annotation that triggers false positive") removed the incorrect assertions. Adding the target domain to the msr_param structure, and calling for each domain separately using smp_call_function_single() means that rdt_ctrl_update() doesn't need to search for the domain. Thus get_domain_from_cpu() can safely assert that the cpus_lock is held since the remaining callers do not use IPI. Signed-off-by: Tony Luck --- arch/x86/kernel/cpu/resctrl/internal.h | 1 + arch/x86/kernel/cpu/resctrl/core.c | 18 ++++------ arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 40 +++++------------------ arch/x86/kernel/cpu/resctrl/rdtgroup.c | 14 +++----- 4 files changed, 21 insertions(+), 52 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index c99f26ebe7a6..c30d7697b431 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -383,6 +383,7 @@ static inline struct rdt_hw_domain *resctrl_to_arch_dom(struct rdt_domain *r) */ struct msr_param { struct rdt_resource *res; + struct rdt_domain *dom; u32 low; u32 high; }; diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 83e40341583e..8d378fc7a50b 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -362,6 +362,8 @@ struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r) { struct rdt_domain *d; + lockdep_assert_cpus_held(); + list_for_each_entry(d, &r->domains, list) { /* Find the domain that contains this CPU */ if (cpumask_test_cpu(cpu, &d->cpu_mask)) @@ -378,19 +380,11 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r) void rdt_ctrl_update(void *arg) { + struct rdt_hw_resource *hw_res; struct msr_param *m = arg; - struct rdt_hw_resource *hw_res = resctrl_to_arch_res(m->res); - struct rdt_resource *r = m->res; - int cpu = smp_processor_id(); - struct rdt_domain *d; - d = get_domain_from_cpu(cpu, r); - if (d) { - hw_res->msr_update(d, m, r); - return; - } - pr_warn_once("cpu %d not found in any domain for resource %s\n", - cpu, r->name); + hw_res = resctrl_to_arch_res(m->res); + hw_res->msr_update(m->dom, m, m->res); } /* @@ -463,6 +457,8 @@ static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d) hw_dom->ctrl_val = dc; setup_default_ctrlval(r, dc); + m.res = r; + m.dom = d; m.low = 0; m.high = hw_res->num_closid; hw_res->msr_update(d, &m, r); diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index 7997b47743a2..a3a0fd80daa8 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -272,22 +272,6 @@ static u32 get_config_index(u32 closid, enum resctrl_conf_type type) } } -static bool apply_config(struct rdt_hw_domain *hw_dom, - struct resctrl_staged_config *cfg, u32 idx, - cpumask_var_t cpu_mask) -{ - struct rdt_domain *dom = &hw_dom->d_resctrl; - - if (cfg->new_ctrl != hw_dom->ctrl_val[idx]) { - cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask); - hw_dom->ctrl_val[idx] = cfg->new_ctrl; - - return true; - } - - return false; -} - int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_domain *d, u32 closid, enum resctrl_conf_type t, u32 cfg_val) { @@ -302,6 +286,7 @@ int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_domain *d, hw_dom->ctrl_val[idx] = cfg_val; msr_param.res = r; + msr_param.dom = d; msr_param.low = idx; msr_param.high = idx + 1; hw_res->msr_update(d, &msr_param, r); @@ -315,27 +300,27 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) struct rdt_hw_domain *hw_dom; struct msr_param msr_param; enum resctrl_conf_type t; - cpumask_var_t cpu_mask; struct rdt_domain *d; + int cpu; u32 idx; /* Walking r->domains, ensure it can't race with cpuhp */ lockdep_assert_cpus_held(); - if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) - return -ENOMEM; - - msr_param.res = NULL; list_for_each_entry(d, &r->domains, list) { hw_dom = resctrl_to_arch_dom(d); + msr_param.res = NULL; + msr_param.dom = d; for (t = 0; t < CDP_NUM_TYPES; t++) { cfg = &hw_dom->d_resctrl.staged_config[t]; if (!cfg->have_new_ctrl) continue; idx = get_config_index(closid, t); - if (!apply_config(hw_dom, cfg, idx, cpu_mask)) + if (cfg->new_ctrl == hw_dom->ctrl_val[idx]) continue; + hw_dom->ctrl_val[idx] = cfg->new_ctrl; + cpu = cpumask_any(&d->cpu_mask); if (!msr_param.res) { msr_param.low = idx; @@ -346,17 +331,10 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) msr_param.high = max(msr_param.high, idx + 1); } } + if (msr_param.res) + smp_call_function_single(cpu, rdt_ctrl_update, &msr_param, 1); } - if (cpumask_empty(cpu_mask)) - goto done; - - /* Update resource control msr on all the CPUs. */ - on_each_cpu_mask(cpu_mask, rdt_ctrl_update, &msr_param, 1); - -done: - free_cpumask_var(cpu_mask); - return 0; } diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 011e17efb1a6..da4f13db4161 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -2813,16 +2813,13 @@ static int reset_all_ctrls(struct rdt_resource *r) struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r); struct rdt_hw_domain *hw_dom; struct msr_param msr_param; - cpumask_var_t cpu_mask; struct rdt_domain *d; + int cpu; int i; /* Walking r->domains, ensure it can't race with cpuhp */ lockdep_assert_cpus_held(); - if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) - return -ENOMEM; - msr_param.res = r; msr_param.low = 0; msr_param.high = hw_res->num_closid; @@ -2834,17 +2831,14 @@ static int reset_all_ctrls(struct rdt_resource *r) */ list_for_each_entry(d, &r->domains, list) { hw_dom = resctrl_to_arch_dom(d); - cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); + cpu = cpumask_any(&d->cpu_mask); for (i = 0; i < hw_res->num_closid; i++) hw_dom->ctrl_val[i] = r->default_ctrl; + msr_param.dom = d; + smp_call_function_single(cpu, rdt_ctrl_update, &msr_param, 1); } - /* Update CBM on all the CPUs in cpu_mask */ - on_each_cpu_mask(cpu_mask, rdt_ctrl_update, &msr_param, 1); - - free_cpumask_var(cpu_mask); - return 0; } -- 2.43.0