From patchwork Thu Jan 28 10:48:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 12053349 X-Patchwork-Delegate: viresh.linux@gmail.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC8CFC433DB for ; Thu, 28 Jan 2021 10:50:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F57864DD8 for ; Thu, 28 Jan 2021 10:50:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229596AbhA1Kuv (ORCPT ); Thu, 28 Jan 2021 05:50:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231494AbhA1Ku0 (ORCPT ); Thu, 28 Jan 2021 05:50:26 -0500 Received: from mail-pf1-x431.google.com (mail-pf1-x431.google.com [IPv6:2607:f8b0:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70934C061788 for ; Thu, 28 Jan 2021 02:49:12 -0800 (PST) Received: by mail-pf1-x431.google.com with SMTP id j12so3723470pfj.12 for ; Thu, 28 Jan 2021 02:49:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=97yz6l0kLDIbGcIxD71cn/hPxZItkULobNVAO0iER9c=; b=dHI5xIfWdsJ+jWKdyY4VLsX8HrTU4Ndfjue0nerF2/CU1IdyUGT01b/j5AZgqlzrnJ NzP6slwCGvhr7jy9+6cGnj29q8AkvyA+uzj+S/qQC83lSthESFgyfogSKuCWuneN6Gv/ 40iY55mp0nybnSSX+EboS2C7ol0PP87yAD5mH5HJW2SH+nHRc+O+5HUNceGT7T3tvc0K a7P3ZzbNm0OU+1gwFTGWJKI9KytDgL5d7D1rnGccxzr2KGMkLu972JmVMb2OfeP8kjQb QYNmizfTpOXm0RJy7FYyS4Y+oaYcPAMFkZGZonHHZ969oqTyzfkZVfLMus/BfSXVWDP5 l8ww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=97yz6l0kLDIbGcIxD71cn/hPxZItkULobNVAO0iER9c=; b=De7AuZB3UWlSA8hthm+QK8uZMTu9OByB4cfzgPR8j2A3qsgwwqULx0lEYUnstVVKhA XFaUsFuv0mvufKDxk95DdD1ZT+aL+W5htK+5BwURCHAw7P1cF10aeJZVDN1B2Jhwz6Ue UHJe/VBLSHNU5fKuh1lbW8XIrTeKL7GzPH7HgBKyOMxk9ceG4IfMGmOiO0wD89qkIwFe QUSUOtD6MMmh+DuWT6wYEeIYR9i+ZsYVKkOcs8ihgitxnGgQ1pUN7DBthYL7puDFrGBL y6c9VgLSsbWaZz+7AX7CRcbqsAzQd4HGfhJxgO/DLziHkUtQkuf6d2M/++Ywj9PGbROw A9oA== X-Gm-Message-State: AOAM533i8YD10+nmyJk18+qoC+k7p48d7Gwh2RtMBNdGQvKGBrq4faUq NfuPuGQ/Gp5bs6bFgb9j3cH+sg== X-Google-Smtp-Source: ABdhPJzXLzSV+BUrNo/bm3UweLs8RDbKETLmPqCea7nR3DhSO6uHdABf7GzdXNssZ+kGuJOTv9viiA== X-Received: by 2002:a65:6a12:: with SMTP id m18mr15605904pgu.178.1611830951994; Thu, 28 Jan 2021 02:49:11 -0800 (PST) Received: from localhost ([122.172.59.240]) by smtp.gmail.com with ESMTPSA id r14sm5790996pgi.27.2021.01.28.02.49.10 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 28 Jan 2021 02:49:11 -0800 (PST) From: Viresh Kumar To: Ionela Voinescu , Rafael Wysocki , Catalin Marinas , Will Deacon Cc: Viresh Kumar , Vincent Guittot , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, Sudeep Holla , Greg Kroah-Hartman Subject: [PATCH V3 1/2] topology: Allow multiple entities to provide sched_freq_tick() callback Date: Thu, 28 Jan 2021 16:18:55 +0530 Message-Id: X-Mailer: git-send-email 2.25.0.rc1.19.g042ed3e048af In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org This patch attempts to make it generic enough so other parts of the kernel can also provide their own implementation of scale_freq_tick() callback, which is called by the scheduler periodically to update the per-cpu freq_scale variable. The implementations now need to provide struct scale_freq_data for the CPUs for which they have hardware counters available, and a callback gets registered for each possible CPU in a per-cpu variable. The arch specific (or ARM AMU) counters are updated to adapt to this and they take the highest priority if they are available, i.e. they will be used instead of CPPC based counters for example. Note that this also defines SCALE_FREQ_SOURCE_CPUFREQ but doesn't use it and it is added to show that cpufreq is also acts as source of information for FIE and will be used by default if no other counters are supported for a platform. Signed-off-by: Viresh Kumar Reported-by: Ionela Voinescu Signed-off-by: Viresh Kumar Reviewed-by: Ionela Voinescu Tested-by: Ionela Voinescu --- arch/arm64/include/asm/topology.h | 10 +--- arch/arm64/kernel/topology.c | 89 ++++++++++++++----------------- drivers/base/arch_topology.c | 56 +++++++++++++++++-- include/linux/arch_topology.h | 14 ++++- 4 files changed, 105 insertions(+), 64 deletions(-) diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h index 3b8dca4eb08d..ec2db3419c41 100644 --- a/arch/arm64/include/asm/topology.h +++ b/arch/arm64/include/asm/topology.h @@ -17,17 +17,9 @@ int pcibus_to_node(struct pci_bus *bus); #include void update_freq_counters_refs(void); -void topology_scale_freq_tick(void); - -#ifdef CONFIG_ARM64_AMU_EXTN -/* - * Replace task scheduler's default counter-based - * frequency-invariance scale factor setting. - */ -#define arch_scale_freq_tick topology_scale_freq_tick -#endif /* CONFIG_ARM64_AMU_EXTN */ /* Replace task scheduler's default frequency-invariant accounting */ +#define arch_scale_freq_tick topology_scale_freq_tick #define arch_set_freq_scale topology_set_freq_scale #define arch_scale_freq_capacity topology_get_freq_scale #define arch_scale_freq_invariant topology_scale_freq_invariant diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index e08a4126453a..1e47dfd465f8 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -199,8 +199,44 @@ static int freq_inv_set_max_ratio(int cpu, u64 max_rate, u64 ref_rate) return 0; } -static DEFINE_STATIC_KEY_FALSE(amu_fie_key); -#define amu_freq_invariant() static_branch_unlikely(&amu_fie_key) +static void amu_scale_freq_tick(void) +{ + u64 prev_core_cnt, prev_const_cnt; + u64 core_cnt, const_cnt, scale; + + prev_const_cnt = this_cpu_read(arch_const_cycles_prev); + prev_core_cnt = this_cpu_read(arch_core_cycles_prev); + + update_freq_counters_refs(); + + const_cnt = this_cpu_read(arch_const_cycles_prev); + core_cnt = this_cpu_read(arch_core_cycles_prev); + + if (unlikely(core_cnt <= prev_core_cnt || + const_cnt <= prev_const_cnt)) + return; + + /* + * /\core arch_max_freq_scale + * scale = ------- * -------------------- + * /\const SCHED_CAPACITY_SCALE + * + * See validate_cpu_freq_invariance_counters() for details on + * arch_max_freq_scale and the use of SCHED_CAPACITY_SHIFT. + */ + scale = core_cnt - prev_core_cnt; + scale *= this_cpu_read(arch_max_freq_scale); + scale = div64_u64(scale >> SCHED_CAPACITY_SHIFT, + const_cnt - prev_const_cnt); + + scale = min_t(unsigned long, scale, SCHED_CAPACITY_SCALE); + this_cpu_write(freq_scale, (unsigned long)scale); +} + +static struct scale_freq_data amu_sfd = { + .source = SCALE_FREQ_SOURCE_ARCH, + .set_freq_scale = amu_scale_freq_tick, +}; static void amu_fie_setup(const struct cpumask *cpus) { @@ -227,7 +263,7 @@ static void amu_fie_setup(const struct cpumask *cpus) if (!invariant && !cpumask_equal(amu_fie_cpus, cpu_present_mask)) return; - static_branch_enable(&amu_fie_key); + topology_set_scale_freq_source(&amu_sfd, amu_fie_cpus); pr_debug("CPUs[%*pbl]: counters will be used for FIE.", cpumask_pr_args(cpus)); @@ -283,53 +319,6 @@ static int __init init_amu_fie(void) } core_initcall(init_amu_fie); -bool arch_freq_counters_available(const struct cpumask *cpus) -{ - return amu_freq_invariant() && - cpumask_subset(cpus, amu_fie_cpus); -} - -void topology_scale_freq_tick(void) -{ - u64 prev_core_cnt, prev_const_cnt; - u64 core_cnt, const_cnt, scale; - int cpu = smp_processor_id(); - - if (!amu_freq_invariant()) - return; - - if (!cpumask_test_cpu(cpu, amu_fie_cpus)) - return; - - prev_const_cnt = this_cpu_read(arch_const_cycles_prev); - prev_core_cnt = this_cpu_read(arch_core_cycles_prev); - - update_freq_counters_refs(); - - const_cnt = this_cpu_read(arch_const_cycles_prev); - core_cnt = this_cpu_read(arch_core_cycles_prev); - - if (unlikely(core_cnt <= prev_core_cnt || - const_cnt <= prev_const_cnt)) - return; - - /* - * /\core arch_max_freq_scale - * scale = ------- * -------------------- - * /\const SCHED_CAPACITY_SCALE - * - * See validate_cpu_freq_invariance_counters() for details on - * arch_max_freq_scale and the use of SCHED_CAPACITY_SHIFT. - */ - scale = core_cnt - prev_core_cnt; - scale *= this_cpu_read(arch_max_freq_scale); - scale = div64_u64(scale >> SCHED_CAPACITY_SHIFT, - const_cnt - prev_const_cnt); - - scale = min_t(unsigned long, scale, SCHED_CAPACITY_SCALE); - this_cpu_write(freq_scale, (unsigned long)scale); -} - #ifdef CONFIG_ACPI_CPPC_LIB #include diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index de8587cc119e..20b511949cd8 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -21,17 +21,65 @@ #include #include +static DEFINE_PER_CPU(struct scale_freq_data *, sft_data); +static struct cpumask scale_freq_counters_mask; + +static bool supports_scale_freq_counters(const struct cpumask *cpus) +{ + return cpumask_subset(cpus, &scale_freq_counters_mask); +} + bool topology_scale_freq_invariant(void) { return cpufreq_supports_freq_invariance() || - arch_freq_counters_available(cpu_online_mask); + supports_scale_freq_counters(cpu_online_mask); +} + +void topology_set_scale_freq_source(struct scale_freq_data *data, + const struct cpumask *cpus) +{ + struct scale_freq_data *sfd; + int cpu; + + for_each_cpu(cpu, cpus) { + sfd = per_cpu(sft_data, cpu); + + /* Use ARCH provided counters whenever possible */ + if (!sfd || sfd->source != SCALE_FREQ_SOURCE_ARCH) { + per_cpu(sft_data, cpu) = data; + cpumask_set_cpu(cpu, &scale_freq_counters_mask); + } + } } +EXPORT_SYMBOL_GPL(topology_set_scale_freq_source); -__weak bool arch_freq_counters_available(const struct cpumask *cpus) +void topology_clear_scale_freq_source(enum scale_freq_source source, + const struct cpumask *cpus) { - return false; + struct scale_freq_data *sfd; + int cpu; + + for_each_cpu(cpu, cpus) { + sfd = per_cpu(sft_data, cpu); + + if (sfd && sfd->source == source) { + per_cpu(sft_data, cpu) = NULL; + cpumask_clear_cpu(cpu, &scale_freq_counters_mask); + } + } } +EXPORT_SYMBOL_GPL(topology_clear_scale_freq_source); + +void topology_scale_freq_tick(void) +{ + struct scale_freq_data *sfd = *this_cpu_ptr(&sft_data); + + if (sfd) + sfd->set_freq_scale(); +} + DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE; +EXPORT_SYMBOL_GPL(freq_scale); void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq, unsigned long max_freq) @@ -47,7 +95,7 @@ void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq, * want to update the scale factor with information from CPUFREQ. * Instead the scale factor will be updated from arch_scale_freq_tick. */ - if (arch_freq_counters_available(cpus)) + if (supports_scale_freq_counters(cpus)) return; scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq; diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 0f6cd6b73a61..3bcfba5c21a7 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -34,7 +34,19 @@ void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq, unsigned long max_freq); bool topology_scale_freq_invariant(void); -bool arch_freq_counters_available(const struct cpumask *cpus); +enum scale_freq_source { + SCALE_FREQ_SOURCE_CPUFREQ = 0, + SCALE_FREQ_SOURCE_ARCH, +}; + +struct scale_freq_data { + enum scale_freq_source source; + void (*set_freq_scale)(void); +}; + +void topology_scale_freq_tick(void); +void topology_set_scale_freq_source(struct scale_freq_data *data, const struct cpumask *cpus); +void topology_clear_scale_freq_source(enum scale_freq_source source, const struct cpumask *cpus); DECLARE_PER_CPU(unsigned long, thermal_pressure);