From patchwork Thu Jun 10 08:24:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 12312261 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=-18.8 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=ham 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 D62B1C48BE0 for ; Thu, 10 Jun 2021 08:24:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B376B613FE for ; Thu, 10 Jun 2021 08:24:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230287AbhFJI0c (ORCPT ); Thu, 10 Jun 2021 04:26:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230251AbhFJI0a (ORCPT ); Thu, 10 Jun 2021 04:26:30 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53069C0617AD for ; Thu, 10 Jun 2021 01:24:24 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id mp5-20020a17090b1905b029016dd057935fso3284756pjb.5 for ; Thu, 10 Jun 2021 01:24:24 -0700 (PDT) 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=ts2ApCK9xnJQUj3HLY0ucjPpblWOxwdFx65VhUgZ2Z4=; b=m3DlcIj/aVptNqUHKX8oUUf+lJ5m3vlVM9aXVU8bLDIOpm2rSnifUHo0xvKS1bmSPP Z9+3xTMFL33TbexfAYLt9ByLW2mLUUFgDeg9JNE178xurzULxbZQuRFaevMs/qUGzubm V8EJzeBp0z+kYLjMIV0xRtqaHvkD220uIBG5erXbcRCk5kYbTBiKwTncOz0krO75n9rw 7Q0opG0COPQHi6Bj+2EKSvUBEZi7OezH8KXfzvc5zAtSjsUF/1h0dIDQ4A7aK34cq+Xm EEtDq/BiUaFJks4VJbbiTYfeb96gHqa+odSnqwWnZbcL/Q/G/D+BmaUyfDmatGU+xeTY BdZA== 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=ts2ApCK9xnJQUj3HLY0ucjPpblWOxwdFx65VhUgZ2Z4=; b=tiBD5ncfYZPIHJf+uq3lyOn6PlbzjPwJLtQGwC4W0HQnN/3Z+xIpHVGSLq6F3ztNg8 99dgovTT6WM7yZx9b7hNYmwvSf2hVQaB0XKTLRBx7YaRNT9Fzaatn/gbhtvYc4oqnAPg foB6giHuqG1Q9ztxwHtCUdPddgQUDvCUl/xCJy43eb/yFgGLUHhxHW9cIm4BqW25pMLI y/HLoNzjyXvPTdwwfDRtSYaUsItIjf6iBL1Dr1lb8+0LQVUQBpKl1P05dlR/xi8JiA3S 8ky25h2F2x5WTEnLuV5xdg7C5OnEf/60kQcEQqYKT6UC2ntLJ7fG++H1ymXE7fWnLzGr kc6w== X-Gm-Message-State: AOAM532ExRm33SlkasFATvQ1CevvbhI+LnjtGpWvh3Q6LT8NM3mNKBEs B8kAQd/bs6ssmnc0GeYMlBukug== X-Google-Smtp-Source: ABdhPJxGEKh8lQGqm26xlut8Bs9isUrJehy0qehJJ01+aGGtE8p7elJr0nyDrya29eyQXQ9z2gQ3XQ== X-Received: by 2002:a17:902:9a8c:b029:113:d891:2eaf with SMTP id w12-20020a1709029a8cb0290113d8912eafmr3878715plp.61.1623313463895; Thu, 10 Jun 2021 01:24:23 -0700 (PDT) Received: from localhost ([136.185.169.128]) by smtp.gmail.com with ESMTPSA id z8sm2081118pgi.94.2021.06.10.01.24.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Jun 2021 01:24:23 -0700 (PDT) From: Viresh Kumar To: Rafael Wysocki , Qian Cai , Viresh Kumar Cc: linux-pm@vger.kernel.org, Vincent Guittot , Ionela Voinescu , linux-kernel@vger.kernel.org Subject: [PATCH 5/5] cpufreq: cppc: Fix suspend/resume specific races with the FIE code Date: Thu, 10 Jun 2021 13:54:01 +0530 Message-Id: <1256ee94a515216ab58553181de175cc74f396bd.1623313323.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 2.31.1.272.g89b43f80a514 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The CPPC driver currently stops the frequency invariance related kthread_work and irq_work from cppc_freq_invariance_exit() which is only called during driver's removal. This is not sufficient as the CPUs can get hot-plugged out while the driver is in use, the same also happens during system suspend/resume. In such a cases we can reach a state where the CPU is removed by the kernel but its kthread_work or irq_work aren't stopped. Fix this by implementing the start_cpu() and stop_cpu() callbacks of the cpufreq core, which will be called for each CPU's addition/removal. The FIE feature was marked BROKEN earlier, revert that. Reported-by: Qian Cai Signed-off-by: Viresh Kumar --- drivers/cpufreq/Kconfig.arm | 1 - drivers/cpufreq/cppc_cpufreq.c | 117 +++++++++++++++++++-------------- 2 files changed, 68 insertions(+), 50 deletions(-) diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index 614c34350f41..a5c5f70acfc9 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -22,7 +22,6 @@ config ACPI_CPPC_CPUFREQ config ACPI_CPPC_CPUFREQ_FIE bool "Frequency Invariance support for CPPC cpufreq driver" depends on ACPI_CPPC_CPUFREQ && GENERIC_ARCH_TOPOLOGY - depends on BROKEN default y help This extends frequency invariance support in the CPPC cpufreq driver, diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 30a861538784..82167c657098 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -74,7 +74,6 @@ struct cppc_freq_invariance { static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv); static struct kthread_worker *kworker_fie; -static bool fie_disabled; static struct cpufreq_driver cppc_cpufreq_driver; static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu); @@ -151,35 +150,64 @@ static struct scale_freq_data cppc_sftd = { .set_freq_scale = cppc_scale_freq_tick, }; -static void cppc_freq_invariance_policy_init(struct cpufreq_policy *policy, - struct cppc_cpudata *cpu_data) +static void cppc_cpufreq_start_cpu(struct cpufreq_policy *policy, + unsigned int cpu) { + struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, cpu); struct cppc_perf_fb_ctrs fb_ctrs = {0}; - struct cppc_freq_invariance *cppc_fi; - int i, ret; + int ret; - if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) - return; + cppc_fi->cpu = cpu; + cppc_fi->cpu_data = policy->driver_data; + kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn); + init_irq_work(&cppc_fi->irq_work, cppc_irq_work); - if (fie_disabled) + ret = cppc_get_perf_ctrs(cpu, &fb_ctrs); + if (ret) { + pr_warn("%s: failed to read perf counters: %d\n", + __func__, ret); return; + } else { + cppc_fi->prev_perf_fb_ctrs = fb_ctrs; + } - for_each_cpu(i, policy->cpus) { - cppc_fi = &per_cpu(cppc_freq_inv, i); - cppc_fi->cpu = i; - cppc_fi->cpu_data = cpu_data; - kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn); - init_irq_work(&cppc_fi->irq_work, cppc_irq_work); + /* Register for freq-invariance */ + topology_set_scale_freq_source(&cppc_sftd, cpumask_of(cpu)); +} - ret = cppc_get_perf_ctrs(i, &fb_ctrs); - if (ret) { - pr_warn("%s: failed to read perf counters: %d\n", - __func__, ret); - fie_disabled = true; - } else { - cppc_fi->prev_perf_fb_ctrs = fb_ctrs; - } - } +static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy, + unsigned int cpu) +{ + struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, cpu); + + topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, cpumask_of(cpu)); + + irq_work_sync(&cppc_fi->irq_work); + kthread_cancel_work_sync(&cppc_fi->work); +} + +static int cppc_freq_invariance_policy_init(struct cpufreq_policy *policy) +{ + int cpu; + + if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) + return 0; + + for_each_cpu(cpu, policy->cpus) + cppc_cpufreq_start_cpu(policy, cpu); + + return 0; +} + +static void cppc_freq_invariance_policy_exit(struct cpufreq_policy *policy) +{ + int cpu; + + if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) + return; + + for_each_cpu(cpu, policy->cpus) + cppc_cpufreq_stop_cpu(policy, cpu); } static void __init cppc_freq_invariance_init(void) @@ -202,9 +230,6 @@ static void __init cppc_freq_invariance_init(void) if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) return; - if (fie_disabled) - return; - kworker_fie = kthread_create_worker(0, "cppc_fie"); if (IS_ERR(kworker_fie)) return; @@ -217,36 +242,28 @@ static void __init cppc_freq_invariance_init(void) return; } - /* Register for freq-invariance */ - topology_set_scale_freq_source(&cppc_sftd, cpu_present_mask); + cppc_cpufreq_driver.start_cpu = cppc_cpufreq_start_cpu; + cppc_cpufreq_driver.stop_cpu = cppc_cpufreq_stop_cpu; } static void cppc_freq_invariance_exit(void) { - struct cppc_freq_invariance *cppc_fi; - int i; - if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) return; - if (fie_disabled) - return; - - topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, cpu_present_mask); - - for_each_possible_cpu(i) { - cppc_fi = &per_cpu(cppc_freq_inv, i); - irq_work_sync(&cppc_fi->irq_work); - } - kthread_destroy_worker(kworker_fie); kworker_fie = NULL; } #else +static inline int +cppc_freq_invariance_policy_init(struct cpufreq_policy *polic) +{ + return 0; +} + static inline void -cppc_freq_invariance_policy_init(struct cpufreq_policy *policy, - struct cppc_cpudata *cpu_data) +cppc_freq_invariance_policy_exit(struct cpufreq_policy *policy) { } @@ -529,11 +546,10 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) if (ret) { pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n", caps->highest_perf, cpu, ret); - } else { - cppc_freq_invariance_policy_init(policy, cpu_data); + return ret; } - return ret; + return cppc_freq_invariance_policy_init(policy); } static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy) @@ -543,6 +559,8 @@ static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy) unsigned int cpu = policy->cpu; int ret; + cppc_freq_invariance_policy_exit(policy); + cpu_data->perf_ctrls.desired_perf = caps->lowest_perf; ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); @@ -728,10 +746,11 @@ static int __init cppc_cpufreq_init(void) INIT_LIST_HEAD(&cpu_data_list); cppc_check_hisi_workaround(); + cppc_freq_invariance_init(); ret = cpufreq_register_driver(&cppc_cpufreq_driver); - if (!ret) - cppc_freq_invariance_init(); + if (ret) + cppc_freq_invariance_exit(); return ret; } @@ -750,8 +769,8 @@ static inline void free_cpu_data(void) static void __exit cppc_cpufreq_exit(void) { - cppc_freq_invariance_exit(); cpufreq_unregister_driver(&cppc_cpufreq_driver); + cppc_freq_invariance_exit(); free_cpu_data(); }