From patchwork Thu Jun 3 05:41:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Vaittinen, Matti" X-Patchwork-Id: 12296301 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B5F2FC47082 for ; Thu, 3 Jun 2021 05:41:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92152613E6 for ; Thu, 3 Jun 2021 05:41:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229762AbhFCFnJ (ORCPT ); Thu, 3 Jun 2021 01:43:09 -0400 Received: from mail-lj1-f171.google.com ([209.85.208.171]:38506 "EHLO mail-lj1-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229738AbhFCFnI (ORCPT ); Thu, 3 Jun 2021 01:43:08 -0400 Received: by mail-lj1-f171.google.com with SMTP id a4so5604059ljd.5; Wed, 02 Jun 2021 22:41:11 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=avHrM7JfdyvFeGpZaxuvTLRbbrJcYYr/B2Y+l11QZLI=; b=nFrZNxyRY5OUywUNdwV5tHOacmSwKk18b4c02satxPJdccmmE+97Kb/g9plgdkuQTB MYEPzvEEg+wk7wxcmqduzdT30Kf2v49myIALvO0LG93GWtKXJRiLUhIy+n3dxLDlZToo 5rv+bwiZyGYppdck+Upk4fQJpVO6MRl3Cqkj3iANhkzxHVExCqofBsaiXP1DI+aumkJJ erj7VOAkr8uw9S+SmoaMQJgMHHZ7cxPTshbwhTjT0ketIlVd8ujKeSfn5jE1wUmHoGLu 4nESdWt1z67hreX4b/BHKvbmOvQYbR1gWyWrlkRo/1hjwuGedxppZgyLWr3WFMulzsvB qHQA== X-Gm-Message-State: AOAM532iKzrjk3dHtQB0RZh6PxzjL3IyPy0TaGfW6Gykj7i4JPbM2DeZ A5Me/d9kl9cf58NQjAPgDbY= X-Google-Smtp-Source: ABdhPJx65Mb0U6+bOzykCIrwAiL5/c73SJ3yyHRMr8zu84Ol76ONfTzz1p4wnCmSVqOF8o2RdMJQaQ== X-Received: by 2002:a2e:979a:: with SMTP id y26mr4689887lji.130.1622698870591; Wed, 02 Jun 2021 22:41:10 -0700 (PDT) Received: from localhost.localdomain (dc7vkhyyyyyyyyyyyyycy-3.rev.dnainternet.fi. [2001:14ba:16e2:8300::4]) by smtp.gmail.com with ESMTPSA id w8sm227523ljj.61.2021.06.02.22.41.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Jun 2021 22:41:10 -0700 (PDT) Date: Thu, 3 Jun 2021 08:41:03 +0300 From: Matti Vaittinen To: Matti Vaittinen , Matti Vaittinen Cc: Mark Brown , Kees Cook , Andy Shevchenko , Zhang Rui , Guenter Roeck , "agross@kernel.org" , "devicetree@vger.kernel.org" , linux-power , "linux-kernel@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-arm-msm@vger.kernel.org" , "bjorn.andersson@linaro.org" , "lgirdwood@gmail.com" , "robh+dt@kernel.org" , Daniel Lezcano , Amit Kucheria , Matteo Croce , Andrew Morton , Petr Mladek , "Rafael J. Wysocki" , Mike Rapoport , Josef Bacik , Kai-Heng Feng , linux-pm@vger.kernel.org Subject: [PATCH RESEND v10 03/11] thermal: Use generic HW-protection shutdown API Message-ID: <5531e89d9e710f5d10e7cdce3ee58957335b9e03.1622628333.git.matti.vaittinen@fi.rohmeurope.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The hardware shutdown function was exported from kernel/reboot for other subsystems to use. Logic is copied from the thermal_core. The protection mutex is replaced by an atomic_t to allow calls also from an IRQ context. Also the WARN() was replaced by pr_emerg() based on discussions here: https://lore.kernel.org/lkml/YJuPwAZroVZ%2Fw633@alley/ and here: https://lore.kernel.org/linux-iommu/20210331093104.383705-4-geert+renesas@glider.be/ Use the exported API instead of implementing own just for the thermal_core. Signed-off-by: Matti Vaittinen Acked-by: Daniel Lezcano --- Changelog: v10: - update commit message to mention changing WARN() to pr_emerg() v9: - Update the thermal documentation v8: - new patch (change added in v7, splitted in own patch at v8) Use the exported API instead --- .../driver-api/thermal/sysfs-api.rst | 24 +++---- drivers/thermal/thermal_core.c | 63 ++----------------- 2 files changed, 13 insertions(+), 74 deletions(-) diff --git a/Documentation/driver-api/thermal/sysfs-api.rst b/Documentation/driver-api/thermal/sysfs-api.rst index 4b638c14bc16..c93fa5e961a0 100644 --- a/Documentation/driver-api/thermal/sysfs-api.rst +++ b/Documentation/driver-api/thermal/sysfs-api.rst @@ -740,21 +740,15 @@ possible. 5. thermal_emergency_poweroff ============================= -On an event of critical trip temperature crossing. Thermal framework -allows the system to shutdown gracefully by calling orderly_poweroff(). -In the event of a failure of orderly_poweroff() to shut down the system -we are in danger of keeping the system alive at undesirably high -temperatures. To mitigate this high risk scenario we program a work -queue to fire after a pre-determined number of seconds to start -an emergency shutdown of the device using the kernel_power_off() -function. In case kernel_power_off() fails then finally -emergency_restart() is called in the worst case. +On an event of critical trip temperature crossing the thermal framework +shuts down the system by calling hw_protection_shutdown(). The +hw_protection_shutdown() first attempts to perform an orderly shutdown +but accepts a delay after which it proceeds doing a forced power-off +or as last resort an emergency_restart. The delay should be carefully profiled so as to give adequate time for -orderly_poweroff(). In case of failure of an orderly_poweroff() the -emergency poweroff kicks in after the delay has elapsed and shuts down -the system. +orderly poweroff. -If set to 0 emergency poweroff will not be supported. So a carefully -profiled non-zero positive value is a must for emergency poweroff to be -triggered. +If the delay is set to 0 emergency poweroff will not be supported. So a +carefully profiled non-zero positive value is a must for emergency +poweroff to be triggered. diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index d20b25f40d19..10a2d8e1cacf 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -36,10 +36,8 @@ static LIST_HEAD(thermal_governor_list); static DEFINE_MUTEX(thermal_list_lock); static DEFINE_MUTEX(thermal_governor_lock); -static DEFINE_MUTEX(poweroff_lock); static atomic_t in_suspend; -static bool power_off_triggered; static struct thermal_governor *def_governor; @@ -327,70 +325,18 @@ static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip) def_governor->throttle(tz, trip); } -/** - * thermal_emergency_poweroff_func - emergency poweroff work after a known delay - * @work: work_struct associated with the emergency poweroff function - * - * This function is called in very critical situations to force - * a kernel poweroff after a configurable timeout value. - */ -static void thermal_emergency_poweroff_func(struct work_struct *work) -{ - /* - * We have reached here after the emergency thermal shutdown - * Waiting period has expired. This means orderly_poweroff has - * not been able to shut off the system for some reason. - * Try to shut down the system immediately using kernel_power_off - * if populated - */ - WARN(1, "Attempting kernel_power_off: Temperature too high\n"); - kernel_power_off(); - - /* - * Worst of the worst case trigger emergency restart - */ - WARN(1, "Attempting emergency_restart: Temperature too high\n"); - emergency_restart(); -} - -static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work, - thermal_emergency_poweroff_func); - -/** - * thermal_emergency_poweroff - Trigger an emergency system poweroff - * - * This may be called from any critical situation to trigger a system shutdown - * after a known period of time. By default this is not scheduled. - */ -static void thermal_emergency_poweroff(void) +void thermal_zone_device_critical(struct thermal_zone_device *tz) { - int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS; /* * poweroff_delay_ms must be a carefully profiled positive value. - * Its a must for thermal_emergency_poweroff_work to be scheduled + * Its a must for forced_emergency_poweroff_work to be scheduled. */ - if (poweroff_delay_ms <= 0) - return; - schedule_delayed_work(&thermal_emergency_poweroff_work, - msecs_to_jiffies(poweroff_delay_ms)); -} + int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS; -void thermal_zone_device_critical(struct thermal_zone_device *tz) -{ dev_emerg(&tz->device, "%s: critical temperature reached, " "shutting down\n", tz->type); - mutex_lock(&poweroff_lock); - if (!power_off_triggered) { - /* - * Queue a backup emergency shutdown in the event of - * orderly_poweroff failure - */ - thermal_emergency_poweroff(); - orderly_poweroff(true); - power_off_triggered = true; - } - mutex_unlock(&poweroff_lock); + hw_protection_shutdown("Temperature too high", poweroff_delay_ms); } EXPORT_SYMBOL(thermal_zone_device_critical); @@ -1538,7 +1484,6 @@ static int __init thermal_init(void) ida_destroy(&thermal_cdev_ida); mutex_destroy(&thermal_list_lock); mutex_destroy(&thermal_governor_lock); - mutex_destroy(&poweroff_lock); return result; } postcore_initcall(thermal_init);