From patchwork Thu Nov 9 15:01:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 13451193 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58DFEC4332F for ; Thu, 9 Nov 2023 15:01:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232193AbjKIPBz (ORCPT ); Thu, 9 Nov 2023 10:01:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232308AbjKIPBy (ORCPT ); Thu, 9 Nov 2023 10:01:54 -0500 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D55E72D62; Thu, 9 Nov 2023 07:01:51 -0800 (PST) Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 5.3.0) id a42070ca4c13ac30; Thu, 9 Nov 2023 16:01:49 +0100 Received: from kreacher.localnet (unknown [195.136.19.94]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by cloudserver094114.home.pl (Postfix) with ESMTPSA id EB14B667CDF; Thu, 9 Nov 2023 16:01:48 +0100 (CET) From: "Rafael J. Wysocki" To: Daniel Lezcano , Linux PM Cc: LKML , "Rafael J. Wysocki" , Zhang Rui , Srinivas Pandruvada , Lukasz Luba Subject: [PATCH v3] thermal: core: Add trip thresholds for trip crossing detection Date: Thu, 09 Nov 2023 16:01:48 +0100 Message-ID: <12346243.O9o76ZdvQC@kreacher> MIME-Version: 1.0 X-CLIENT-IP: 195.136.19.94 X-CLIENT-HOSTNAME: 195.136.19.94 X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedvkedruddvuddgjedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecujffqoffgrffnpdggtffipffknecuuegrihhlohhuthemucduhedtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvfevufffkfgggfgtsehtufertddttdejnecuhfhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqnecuggftrfgrthhtvghrnhepgeffhfdujeelhfdtgeffkeetudfhtefhhfeiteethfekvefgvdfgfeeikeeigfehnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphepudelhedrudefiedrudelrdelgeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeduleehrddufeeirdduledrleegpdhhvghlohepkhhrvggrtghhvghrrdhlohgtrghlnhgvthdpmhgrihhlfhhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqpdhnsggprhgtphhtthhopeejpdhrtghpthhtohepuggrnhhivghlrdhlvgiitggrnhhosehlihhnrghrohdrohhrghdprhgtphhtthhopehlihhnuhigqdhpmhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehrrghfrggvlheskhgvrhhnvghl rdhorhhgpdhrtghpthhtoheprhhuihdriihhrghnghesihhnthgvlhdrtghomhdprhgtphhtthhopehsrhhinhhivhgrshdrphgrnhgurhhuvhgruggrsehlihhnuhigrdhinhhtvghlrdgtohhm X-DCC--Metrics: v370.home.net.pl 1024; Body=7 Fuz1=7 Fuz2=7 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki The trip crossing detection in handle_thermal_trip() does not work correctly in the cases when a trip point is crossed on the way up and then the zone temperature stays above its low temperature (that is, its temperature decreased by its hysteresis). The trip temperature may be passed by the zone temperature subsequently in that case, even multiple times, but that does not count as the trip crossing as long as the zone temperature does not fall below the trip's low temperature or, in other words, until the trip is crossed on the way down. |-----------low--------high------------| |<--------->| | hyst | | | | -|--> crossed on the way up | <---|-- crossed on the way down However, handle_thermal_trip() will invoke thermal_notify_tz_trip_up() every time the trip temperature is passed by the zone temperature on the way up regardless of whether or not the trip has been crossed on the way down yet. Moreover, it will not call thermal_notify_tz_trip_down() if the last zone temperature was between the trip's temperature and its low temperature, so some "trip crossed on the way down" events may not be reported. To address this issue, introduce trip thresholds equal to either the temperature of the given trip, or its low temperature, such that if the trip's threshold is passed by the zone temperature on the way up, its value will be set to the trip's low temperature and thermal_notify_tz_trip_up() will be called, and if the trip's threshold is passed by the zone temperature on the way down, its value will be set to the trip's temperature (high) and thermal_notify_tz_trip_down() will be called. Accordingly, if the threshold is passed on the way up, it cannot be passed on the way up again until its passed on the way down and if it is passed on the way down, it cannot be passed on the way down again until it is passed on the way up which guarantees correct triggering of trip crossing notifications. If the last temperature of the zone is invalid, the trip's threshold will be set depending of the zone's current temperature: If that temperature is above the trip's temperature, its threshold will be set to its low temperature or otherwise its threshold will be set to its (high) temperature. Because the zone temperature is initially set to invalid and tz->last_temperature is only updated by update_temperature(), this is sufficient to set the correct initial threshold values for all trips. Link: https://lore.kernel.org/all/20220718145038.1114379-4-daniel.lezcano@linaro.org Signed-off-by: Rafael J. Wysocki --- v2 -> v3: Take possible changes of trip point temperature or hysteresis into account. v1 (RFC) -> v2: Add missing description of a new struct thermal_trip field. --- drivers/thermal/thermal_core.c | 43 ++++++++++++++++++++++++++++++++++------- include/linux/thermal.h | 2 + 2 files changed, 38 insertions(+), 7 deletions(-) Index: linux-pm/drivers/thermal/thermal_core.c =================================================================== --- linux-pm.orig/drivers/thermal/thermal_core.c +++ linux-pm/drivers/thermal/thermal_core.c @@ -345,22 +345,51 @@ static void handle_critical_trips(struct } static void handle_thermal_trip(struct thermal_zone_device *tz, - const struct thermal_trip *trip) + struct thermal_trip *trip) { if (trip->temperature == THERMAL_TEMP_INVALID) return; - if (tz->last_temperature != THERMAL_TEMP_INVALID) { - if (tz->last_temperature < trip->temperature && - tz->temperature >= trip->temperature) + if (tz->last_temperature == THERMAL_TEMP_INVALID) { + /* Initialization. */ + trip->threshold = trip->temperature; + if (tz->temperature >= trip->threshold) + trip->threshold -= trip->hysteresis; + } else if (tz->last_temperature < trip->threshold) { + /* + * The trip threshold is equal to the trip temperature, unless + * the latter has changed in the meantime. In either case, + * the trip is crossed if the current zone temperature is at + * least equal to its temperature, but otherwise ensure that + * the threshold and the trip temperature will be equal. + */ + if (tz->temperature >= trip->temperature) { thermal_notify_tz_trip_up(tz->id, thermal_zone_trip_id(tz, trip), tz->temperature); - if (tz->last_temperature >= trip->temperature && - tz->temperature < trip->temperature - trip->hysteresis) + trip->threshold = trip->temperature - trip->hysteresis; + } else { + trip->threshold = trip->temperature; + } + } else { + /* + * The previous zone temperature was above or equal to the trip + * threshold, which would be equal to the "low temperature" of + * the trip (its temperature minus its hysteresis), unless the + * trip temperature or hysteresis had changed. In either case, + * the trip is crossed if the current zone temperature is below + * the low temperature of the trip, but otherwise ensure that + * the trip threshold will be equal to the low temperature of + * the trip. + */ + if (tz->temperature < trip->temperature - trip->hysteresis) { thermal_notify_tz_trip_down(tz->id, thermal_zone_trip_id(tz, trip), tz->temperature); + trip->threshold = trip->temperature; + } else { + trip->threshold = trip->temperature - trip->hysteresis; + } } if (trip->type == THERMAL_TRIP_CRITICAL || trip->type == THERMAL_TRIP_HOT) @@ -403,7 +432,7 @@ static void thermal_zone_device_init(str void __thermal_zone_device_update(struct thermal_zone_device *tz, enum thermal_notify_event event) { - const struct thermal_trip *trip; + struct thermal_trip *trip; if (atomic_read(&in_suspend)) return; Index: linux-pm/include/linux/thermal.h =================================================================== --- linux-pm.orig/include/linux/thermal.h +++ linux-pm/include/linux/thermal.h @@ -57,12 +57,14 @@ enum thermal_notify_event { * struct thermal_trip - representation of a point in temperature domain * @temperature: temperature value in miliCelsius * @hysteresis: relative hysteresis in miliCelsius + * @threshold: trip crossing notification threshold miliCelsius * @type: trip point type * @priv: pointer to driver data associated with this trip */ struct thermal_trip { int temperature; int hysteresis; + int threshold; enum thermal_trip_type type; void *priv; };