From patchwork Wed Jun 1 15:14:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Lezcano X-Patchwork-Id: 578018 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 AD0A6CCA473 for ; Wed, 1 Jun 2022 15:15:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238872AbiFAPPH (ORCPT ); Wed, 1 Jun 2022 11:15:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354961AbiFAPPA (ORCPT ); Wed, 1 Jun 2022 11:15:00 -0400 Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02C9191552 for ; Wed, 1 Jun 2022 08:14:59 -0700 (PDT) Received: by mail-wr1-x42b.google.com with SMTP id k16so2805458wrg.7 for ; Wed, 01 Jun 2022 08:14:58 -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:mime-version :content-transfer-encoding; bh=LHnieHEw4RPGKoOIEHTzAQkLNeagtaYCFgNXH9dPMac=; b=cRdEo239VtaUXETw8ISO74XI8xvlfNc4i6PeNXes20SRN+U49YXxawZ22ws9eo+uGW 08YhaRFvqcL30b0APelTlZaKS/b91/6+aN/n7rRGlmbEGzHzt/RQpqtNic67opWgnOxv Q9yvdI9SIWSgKm1qDasS1on1xvQSJ6xxc6Rba4P5fjryXHMJoWjnLezdtKkhhUf74KBc lgbHtnWnG/bzht7LlMafWPzF/F18JdjX71KzxvJ1ExBqjxA3DAcWnjX078B//XTIGABW XHiPSH+tWHJoIYUIs6+DXYPdcyOx6PRIN7X8x362YocTWFqWypP4pbT2iVX8hzs+hooR vLtA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=LHnieHEw4RPGKoOIEHTzAQkLNeagtaYCFgNXH9dPMac=; b=bspQ0cIWdL+aNhpOknyMNX0KEj5NkHsE1mjr/sfavkODGJT6cj7XSV42SkKZiteoP9 NcoNNN5Swqmrns/kqp/xRAbBfZUMu/A98HvcdYAyKXdboH3VF19h65phjS7bI9YEVSfi Rw5v+NXOf/Lgye3XwglYjeQkkNoRQTeeakelW6R650oPKeCFt3o/G85y/O9neXkAK+pS XFhmauzr8Y2jE5XnR2U3L/54hCaSrsXfacVsLk8j1W7tyPW6J3paYCApBLPAewfGNpAt EaCdvLbv7p8x+MMu9+7Y864I26HDFTLQTz8GkZN2m93KFQUXOcrm+KyhNBtwnJ//V78w 7Sog== X-Gm-Message-State: AOAM5312wmJpwQFGxMpa4rGBvwC5LgFKeBB4hhb3HcqH8dfe6SOOHIIy vJ/5QDiVQxTUBfH0fWpwMt5I4Q== X-Google-Smtp-Source: ABdhPJyvsaFdVNck29C4extor+IlOzl9uYZ5uxE6guTkWtBxC73ZOWwV/rDc7ugpxlSVciZH79tmJA== X-Received: by 2002:adf:f582:0:b0:210:f0:24ac with SMTP id f2-20020adff582000000b0021000f024acmr251274wro.444.1654096497485; Wed, 01 Jun 2022 08:14:57 -0700 (PDT) Received: from localhost.localdomain (176-182-171-101.abo.bbox.fr. [176.182.171.101]) by smtp.gmail.com with ESMTPSA id y5-20020adff6c5000000b0020c5253d926sm1882077wrp.114.2022.06.01.08.14.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Jun 2022 08:14:56 -0700 (PDT) From: Daniel Lezcano To: daniel.lezcano@linaro.org, rafael@kernel.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_manafm@quicinc.com, Amit Kucheria , Zhang Rui Subject: [PATCH 1/3] thermal/core: Encapsulate the set_cur_state function Date: Wed, 1 Jun 2022 17:14:39 +0200 Message-Id: <20220601151441.9128-1-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Concentrate the actions in a single place when a cooling device state is changed. Provide a function to do that instead of calling the underlying ops. Signed-off-by: Daniel Lezcano --- drivers/thermal/thermal_core.h | 1 + drivers/thermal/thermal_helpers.c | 32 ++++++++++++++++++++++++------- drivers/thermal/thermal_sysfs.c | 7 ++----- 3 files changed, 28 insertions(+), 12 deletions(-) diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 726e327b4205..4689f6cf898f 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -65,6 +65,7 @@ static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev) cdev->ops->power2state; } +int thermal_cdev_set_state(struct thermal_cooling_device *cdev, int state); void thermal_cdev_update(struct thermal_cooling_device *); void __thermal_cdev_update(struct thermal_cooling_device *cdev); diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c index 3edd047e144f..d5f162fad1ab 100644 --- a/drivers/thermal/thermal_helpers.c +++ b/drivers/thermal/thermal_helpers.c @@ -182,14 +182,32 @@ void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms) *delay_jiffies = round_jiffies(*delay_jiffies); } -static void thermal_cdev_set_cur_state(struct thermal_cooling_device *cdev, - int target) +/** + * thermal_cdev_set_state - set the cooling device state + * @cdev: a pointer to a thermal_cooling_device + * @state: the target state + * + * Set the state of the cooling device passed as parameter. The + * cooling device lock must be held when calling this function. + * + * Return: 0 in case of success, otherwise the return value is the one + * returned by the backend for the ops + */ +int thermal_cdev_set_state(struct thermal_cooling_device *cdev, int state) { - if (cdev->ops->set_cur_state(cdev, target)) - return; + int ret; - thermal_notify_cdev_state_update(cdev->id, target); - thermal_cooling_device_stats_update(cdev, target); + /* + * No check is needed for the ops->set_cur_state as the + * registering function checked the ops are correctly set + */ + ret = cdev->ops->set_cur_state(cdev, state); + if (!ret) { + thermal_notify_cdev_state_update(cdev->id, state); + thermal_cooling_device_stats_update(cdev, state); + } + + return ret; } void __thermal_cdev_update(struct thermal_cooling_device *cdev) @@ -207,7 +225,7 @@ void __thermal_cdev_update(struct thermal_cooling_device *cdev) target = instance->target; } - thermal_cdev_set_cur_state(cdev, target); + thermal_cdev_set_state(cdev, target); trace_cdev_update(cdev, target); dev_dbg(&cdev->device, "set to state %lu\n", target); diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index 1c4aac8464a7..935e79909121 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -617,12 +617,9 @@ cur_state_store(struct device *dev, struct device_attribute *attr, return -EINVAL; mutex_lock(&cdev->lock); - - result = cdev->ops->set_cur_state(cdev, state); - if (!result) - thermal_cooling_device_stats_update(cdev, state); - + result = thermal_cdev_set_state(cdev, state); mutex_unlock(&cdev->lock); + return result ? result : count; } From patchwork Wed Jun 1 15:14:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Lezcano X-Patchwork-Id: 578361 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 8BF07C433EF for ; Wed, 1 Jun 2022 15:15:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354961AbiFAPPI (ORCPT ); Wed, 1 Jun 2022 11:15:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354985AbiFAPPC (ORCPT ); Wed, 1 Jun 2022 11:15:02 -0400 Received: from mail-wr1-x430.google.com (mail-wr1-x430.google.com [IPv6:2a00:1450:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA50390CFA for ; Wed, 1 Jun 2022 08:15:00 -0700 (PDT) Received: by mail-wr1-x430.google.com with SMTP id p10so2784470wrg.12 for ; Wed, 01 Jun 2022 08:15:00 -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=jlAz9A27qP0uAwYahd1NHsUql8CrfwMJT64PfEqDJMI=; b=kNFa3FVHpmOpee0ov9lHYqpmsQPsVFKvOFXdMws1goL+fcdBmdkpayFsqyu5WJdDui lIs/kYmB2pV7cFtha1kWmdYntxkTvN6N9ZAGFN+/F6PXrTqWMdFcGx6uAFalBZvKuanB rU1sSd2ihYJHHPdvxbwhuHKk7BbS8cVi7/rPzh/3w6fWnIRm7FUYdnOSPrRRkMyLJmwJ GtlCbcB45EZLTmAuia7dbJ4gZAr34Zf7X7rQzQBOaDsxz2VIq0zZnbA152Vk+xg2dDC8 yM0/6qFWIjYWxNAGteUgeRA4JeOWdUWvDtGdEkobXK/XpGTgjR/r1P0LvovD07fdI2fb MzQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jlAz9A27qP0uAwYahd1NHsUql8CrfwMJT64PfEqDJMI=; b=1nTUR3NdEdW/ewoheWpEAJtkQAtdAw1+fRmufNilKBaQsw2bzAg+Wf5QLo/+E71js0 gLmoF8sYIPvsU2I69zY0vErWONbMneSdozGVb42N6G4bO81rtyTFM+EKOCa+kzYPZ3l8 3BhINdr+yv3a1iY2ebr3yk0tKt11aKxrWBIEH94eSCUni9UPd6MZ3vMtxd4EAiWevsWx 5fphEt7U4DeSdm/VvEGfCK9oJRI22lT+uIcypQYwaX0qUBe2ZO4g51FU7ba9cL3geSc3 R2GTOCSMgUkqMGUUP6UxYpcdA0uJwEtNHGNtFfd+KzgdArE3jwsjWs3ynqDCJxTyByjn 2e/g== X-Gm-Message-State: AOAM531kcCbzIRqLgbPHG1aKitOeGpaaSWku4blWV+O3KqTlkbbMf3Dy I/L2URd8YqkDAoEwd/7bN7+Tjg== X-Google-Smtp-Source: ABdhPJxtJvO+YkKSAiJWREsk+b+J81DXBGYIb6OjJ1+rwq/de2T760Q5FYiqP6eMRM7bewQTvWeGng== X-Received: by 2002:a05:6000:2a9:b0:210:2530:be32 with SMTP id l9-20020a05600002a900b002102530be32mr231684wry.153.1654096499280; Wed, 01 Jun 2022 08:14:59 -0700 (PDT) Received: from localhost.localdomain (176-182-171-101.abo.bbox.fr. [176.182.171.101]) by smtp.gmail.com with ESMTPSA id y5-20020adff6c5000000b0020c5253d926sm1882077wrp.114.2022.06.01.08.14.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Jun 2022 08:14:58 -0700 (PDT) From: Daniel Lezcano To: daniel.lezcano@linaro.org, rafael@kernel.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_manafm@quicinc.com, Amit Kucheria , Zhang Rui Subject: [PATCH 2/3] thermal/debugfs: Add debugfs information Date: Wed, 1 Jun 2022 17:14:40 +0200 Message-Id: <20220601151441.9128-2-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220601151441.9128-1-daniel.lezcano@linaro.org> References: <20220601151441.9128-1-daniel.lezcano@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The thermal framework does not have any debug information except a sysfs stat which is a bit controversial. This one allocates big chunks of memory for every cooling devices with a high number of states and could represent on some systems in production several megabytes of memory for just a portion of it. As the syfs is limited to a page size, the output is not exploitable with large data array and gets truncated. The patch provides the same information than sysfs except the transitions are dynamically allocated, thus they won't represent more events than the ones which actually occured. There is no longer a size limitation and it opens the field for more debugging information where the debugfs is designed for, not sysfs. Signed-off-by: Daniel Lezcano Reported-by: kernel test robot --- drivers/thermal/Kconfig | 7 + drivers/thermal/Makefile | 3 + drivers/thermal/thermal_core.c | 10 + drivers/thermal/thermal_core.h | 1 + drivers/thermal/thermal_debugfs.c | 362 ++++++++++++++++++++++++++++++ drivers/thermal/thermal_debugfs.h | 17 ++ drivers/thermal/thermal_helpers.c | 1 + include/linux/thermal.h | 7 + 8 files changed, 408 insertions(+) create mode 100644 drivers/thermal/thermal_debugfs.c create mode 100644 drivers/thermal/thermal_debugfs.h diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 0e5cc948373c..42400c6aed61 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -33,6 +33,13 @@ config THERMAL_STATISTICS If in doubt, say N. +config THERMAL_DEBUGFS + bool "Thermal debugging file system" + depends on DEBUG_FS + help + This option provides a debugfs entry giving useful + information about the thermal framework internals. + config THERMAL_EMERGENCY_POWEROFF_DELAY_MS int "Emergency poweroff delay in milli-seconds" default 0 diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index def8e1a0399c..1d498fa1beba 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -10,6 +10,9 @@ thermal_sys-y += thermal_core.o thermal_sysfs.o \ # netlink interface to manage the thermal framework thermal_sys-$(CONFIG_THERMAL_NETLINK) += thermal_netlink.o +# debugfs interface to investigate the behavior and statistics +thermal_sys-$(CONFIG_THERMAL_DEBUGFS) += thermal_debugfs.o + # interface to/from other layers providing sensors thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o thermal_sys-$(CONFIG_THERMAL_OF) += thermal_of.o diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index cdc0552e8c42..a2d6eb0d0895 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -944,6 +944,8 @@ __thermal_cooling_device_register(struct device_node *np, THERMAL_EVENT_UNSPECIFIED); mutex_unlock(&thermal_list_lock); + thermal_debugfs_cdev_register(cdev); + return cdev; out_kfree_type: @@ -1079,6 +1081,8 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev) if (!cdev) return; + thermal_debugfs_cdev_unregister(cdev); + mutex_lock(&thermal_list_lock); list_for_each_entry(pos, &thermal_cdev_list, node) if (pos == cdev) @@ -1311,6 +1315,8 @@ thermal_zone_device_register(const char *type, int trips, int mask, thermal_notify_tz_create(tz->id, tz->type); + thermal_debugfs_tz_register(tz); + return tz; unregister: @@ -1340,6 +1346,8 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) if (!tz) return; + thermal_debugfs_tz_unregister(tz); + tzp = tz->tzp; tz_id = tz->id; @@ -1485,6 +1493,8 @@ static int __init thermal_init(void) pr_warn("Thermal: Can not register suspend notifier, return %d\n", result); + thermal_debugfs_init(); + return 0; unregister_class: diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 4689f6cf898f..49331b8a5404 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -13,6 +13,7 @@ #include #include "thermal_netlink.h" +#include "thermal_debugfs.h" /* Default Thermal Governor */ #if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE) diff --git a/drivers/thermal/thermal_debugfs.c b/drivers/thermal/thermal_debugfs.c new file mode 100644 index 000000000000..d22558d06da0 --- /dev/null +++ b/drivers/thermal/thermal_debugfs.c @@ -0,0 +1,362 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2022 Linaro Limited + * + * Author: Daniel Lezcano + * + * Debug filesystem for thermal framework + */ +#include +#include +#include +#include +#include + +static struct dentry *rootd; +static struct dentry *cdevd; +static struct dentry *tzd; + +/* + * Length of the string containing the thermal zone id, including the + * ending null character. We can reasonably assume there won't be more + * than 256 thermal zones as the maximum observed today is around 32. + */ +#define IDSLENGTH 4 + +/* + * The cooling device transition list is stored in a hash table where + * the size is CDEVSTATS_HASH_SIZE. The majority of cooling devices + * have dozen of states but some can have much more, so a hash table + * is more adequate in this case because browsing the entire list when + * storing the transitions could have a non neglictible cost + */ +#define CDEVSTATS_HASH_SIZE 16 + +struct cdev_value { + struct list_head list; + int id; + u64 value; +}; + +struct cdev_debugfs { + u32 total; + int current_state; + ktime_t timestamp; + struct mutex lock; + struct list_head trans_list[CDEVSTATS_HASH_SIZE]; + struct list_head duration_list[CDEVSTATS_HASH_SIZE]; +}; + +struct thermal_debugfs { + struct dentry *d_top; + union { + struct cdev_debugfs cdev; + }; +}; + +void thermal_debugfs_init(void) +{ + rootd = debugfs_create_dir("thermal", NULL); + if (!rootd) + return; + + cdevd = debugfs_create_dir("cooling_devices", rootd); + if (!cdevd) + return; + + tzd = debugfs_create_dir("thermal_zones", rootd); +} + +static struct thermal_debugfs *thermal_debugfs_add_id(struct dentry *d, int id) +{ + struct thermal_debugfs *dfs; + char ids[IDSLENGTH]; + + dfs = kzalloc(sizeof(*dfs), GFP_KERNEL); + if (!dfs) + return NULL; + + snprintf(ids, IDSLENGTH, "%d", id); + + dfs->d_top = debugfs_create_dir(ids, d); + if (!dfs->d_top) { + kfree(dfs); + return NULL; + } + + return dfs; +} + +static void thermal_debugfs_remove_id(struct thermal_debugfs *dfs) +{ + if (!dfs) + return; + + debugfs_remove(dfs->d_top); + kfree(dfs); +} + +static struct cdev_value *thermal_debugfs_cdev_value_alloc(int id) +{ + struct cdev_value *cdev_value; + + cdev_value = kzalloc(sizeof(*cdev_value), GFP_KERNEL); + if (cdev_value) { + cdev_value->id = id; + INIT_LIST_HEAD(&cdev_value->list); + } + + return cdev_value; +} + +static struct cdev_value *thermal_debugfs_cdev_value_find(struct thermal_debugfs *dfs, + struct list_head *list, int id) +{ + struct cdev_value *pos; + + list_for_each_entry(pos, &list[id % CDEVSTATS_HASH_SIZE], list) + if (pos->id == id) + return pos; + + return NULL; +} + +static void thermal_debugfs_cdev_value_insert(struct thermal_debugfs *dfs, + struct list_head *list, + struct cdev_value *cdev_value) +{ + list_add_tail(&cdev_value->list, &list[cdev_value->id % CDEVSTATS_HASH_SIZE]); +} + +struct cdev_value *thermal_debugfs_cdev_value_get(struct thermal_debugfs *dfs, + struct list_head *list, int id) +{ + struct cdev_value *cdev_value; + + cdev_value = thermal_debugfs_cdev_value_find(dfs, list, id); + if (cdev_value) + return cdev_value; + + cdev_value = thermal_debugfs_cdev_value_alloc(id); + if (cdev_value) + thermal_debugfs_cdev_value_insert(dfs, list, cdev_value); + + return cdev_value; +} + +static void thermal_debugfs_cdev_reset(struct cdev_debugfs *cfs) +{ + int i; + struct cdev_value *pos, *tmp; + + for (i = 0; i < CDEVSTATS_HASH_SIZE; i++) { + + list_for_each_entry_safe(pos, tmp, &cfs->trans_list[i], list) { + list_del(&pos->list); + kfree(pos); + } + + list_for_each_entry_safe(pos, tmp, &cfs->duration_list[i], list) { + list_del(&pos->list); + kfree(pos); + } + } + + cfs->total = 0; +} + +void thermal_debugfs_cdev_transition(struct thermal_cooling_device *cdev, int to) +{ + struct thermal_debugfs *dfs = cdev->debugfs; + struct cdev_debugfs *cfs; + struct cdev_value *cdev_value; + ktime_t now = ktime_get(); + int transition, from; + + if (!dfs || (dfs->cdev.current_state == to)) + return; + + cfs = &dfs->cdev; + + mutex_lock(&cfs->lock); + + from = cfs->current_state; + cfs->current_state = to; + transition = (from << 16) | to; + + cdev_value = thermal_debugfs_cdev_value_get(dfs, cfs->duration_list, from); + if (cdev_value) { + cdev_value->value += ktime_ms_delta(now, cfs->timestamp); + cfs->timestamp = now; + } + + cdev_value = thermal_debugfs_cdev_value_get(dfs, cfs->trans_list, transition); + if (cdev_value) + cdev_value->value++; + + cfs->total++; + + mutex_unlock(&cfs->lock); +} + +static void *cdev_seq_start(struct seq_file *s, loff_t *pos) +{ + struct cdev_debugfs *cfs = s->private; + + mutex_lock(&cfs->lock); + + return (*pos < CDEVSTATS_HASH_SIZE) ? pos : NULL; +} + +static void *cdev_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + (*pos)++; + + return (*pos < CDEVSTATS_HASH_SIZE) ? pos : NULL; +} + +static void cdev_seq_stop(struct seq_file *s, void *v) +{ + struct cdev_debugfs *cfs = s->private; + + mutex_unlock(&cfs->lock); +} + +static int cdev_tt_seq_show(struct seq_file *s, void *v) +{ + struct cdev_debugfs *cfs = s->private; + struct list_head *trans_list = cfs->trans_list; + struct cdev_value *pos; + char buffer[11]; + int i = *(loff_t *)v; + + if (!i) + seq_puts(s, "Transition\tHits\n"); + + list_for_each_entry(pos, &trans_list[i], list) { + + snprintf(buffer, ARRAY_SIZE(buffer) - 1, "%d->%d", + pos->id >> 16, pos->id & 0xFFFF); + + seq_printf(s, "%-10s\t%-10llu\n", buffer, pos->value); + } + + return 0; +} + +static const struct seq_operations tt_sops = { + .start = cdev_seq_start, + .next = cdev_seq_next, + .stop = cdev_seq_stop, + .show = cdev_tt_seq_show, +}; + +DEFINE_SEQ_ATTRIBUTE(tt); + +static int cdev_dt_seq_show(struct seq_file *s, void *v) +{ + struct cdev_debugfs *cfs = s->private; + struct list_head *duration_list = cfs->duration_list; + struct cdev_value *pos; + int i = *(loff_t *)v; + + if (!i) + seq_puts(s, "State\tTime\n"); + + list_for_each_entry(pos, &duration_list[i], list) { + s64 duration = pos->value; + + if (pos->id == cfs->current_state) + duration += ktime_ms_delta(ktime_get(), cfs->timestamp); + + seq_printf(s, "%-5d\t%-10llu\n", pos->id, duration); + } + + return 0; +} + +static const struct seq_operations dt_sops = { + .start = cdev_seq_start, + .next = cdev_seq_next, + .stop = cdev_seq_stop, + .show = cdev_dt_seq_show, +}; + +DEFINE_SEQ_ATTRIBUTE(dt); + +static int cdev_reset_set(void *data, u64 val) +{ + struct cdev_debugfs *cfs = data; + + if (!val) + return -EINVAL; + + thermal_debugfs_cdev_reset(cfs); + + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(cdev_reset_fops, NULL, cdev_reset_set, "%llu\n"); + +void thermal_debugfs_cdev_register(struct thermal_cooling_device *cdev) +{ + struct thermal_debugfs *dfs; + struct cdev_debugfs *cfs; + int i; + + if (!cdevd) + return; + + dfs = thermal_debugfs_add_id(cdevd, cdev->id); + if (!dfs) + return; + + cfs = &dfs->cdev; + + for (i = 0; i < CDEVSTATS_HASH_SIZE; i++) { + INIT_LIST_HEAD(&cfs->trans_list[i]); + INIT_LIST_HEAD(&cfs->duration_list[i]); + } + + mutex_init(&cfs->lock); + cfs->current_state = 0; + cfs->timestamp = ktime_get(); + + debugfs_create_file("trans_table", 0400, dfs->d_top, cfs, &tt_fops); + + debugfs_create_file("time_in_state_ms", 0400, dfs->d_top, cfs, &dt_fops); + + debugfs_create_file("reset", 0200, dfs->d_top, cfs, &cdev_reset_fops); + + debugfs_create_u32("total_trans", 0400, dfs->d_top, &cfs->total); + + cdev->debugfs = dfs; +} + +void thermal_debugfs_cdev_unregister(struct thermal_cooling_device *cdev) +{ + struct thermal_debugfs *dfs = cdev->debugfs; + + if (!dfs) + return; + + debugfs_remove(dfs->d_top); + thermal_debugfs_cdev_reset(&dfs->cdev); + cdev->debugfs = NULL; + kfree(dfs); +} + +void thermal_debugfs_tz_register(struct thermal_zone_device *tz) +{ + if (!tz) + return; + + tz->debugfs = thermal_debugfs_add_id(tzd, tz->id); +} + +void thermal_debugfs_tz_unregister(struct thermal_zone_device *tz) +{ + thermal_debugfs_remove_id(tz->debugfs); + + tz->debugfs = NULL; +} diff --git a/drivers/thermal/thermal_debugfs.h b/drivers/thermal/thermal_debugfs.h new file mode 100644 index 000000000000..529f5bda931b --- /dev/null +++ b/drivers/thermal/thermal_debugfs.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifdef CONFIG_THERMAL_DEBUGFS +void thermal_debugfs_init(void); +void thermal_debugfs_cdev_register(struct thermal_cooling_device *cdev); +void thermal_debugfs_cdev_unregister(struct thermal_cooling_device *cdev); +void thermal_debugfs_tz_register(struct thermal_zone_device *tz); +void thermal_debugfs_tz_unregister(struct thermal_zone_device *tz); +void thermal_debugfs_cdev_transition(struct thermal_cooling_device *cdev, int state); +#else +static inline void thermal_debugfs_init(void); +static inline void thermal_debugfs_cdev_register(struct thermal_cooling_device *cdev) {} +static inline void thermal_debugfs_cdev_unregister(struct thermal_cooling_device *cdev) {} +static inline void thermal_debugfs_tz_register(struct thermal_zone_device *tz) {} +static inline void thermal_debugfs_tz_unregister(struct thermal_zone_device *tz) {} +static inline void thermal_debugfs_cdev_transition(struct thermal_cooling_device *cdev, int state) {} +#endif /* CONFIG_THERMAL_DEBUGFS */ diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c index d5f162fad1ab..040d9e9b55e1 100644 --- a/drivers/thermal/thermal_helpers.c +++ b/drivers/thermal/thermal_helpers.c @@ -205,6 +205,7 @@ int thermal_cdev_set_state(struct thermal_cooling_device *cdev, int state) if (!ret) { thermal_notify_cdev_state_update(cdev->id, state); thermal_cooling_device_stats_update(cdev, state); + thermal_debugfs_cdev_transition(cdev, state); } return ret; diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 365733b428d8..4a69e8a6868e 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -34,6 +34,7 @@ struct thermal_zone_device; struct thermal_cooling_device; struct thermal_instance; +struct thermal_debugfs; struct thermal_attr; enum thermal_trend { @@ -101,6 +102,9 @@ struct thermal_cooling_device { struct mutex lock; /* protect thermal_instances list */ struct list_head thermal_instances; struct list_head node; +#ifdef CONFIG_THERMAL_DEBUGFS + struct thermal_debugfs *debugfs; +#endif }; /** @@ -174,6 +178,9 @@ struct thermal_zone_device { struct list_head node; struct delayed_work poll_queue; enum thermal_notify_event notify_event; +#ifdef CONFIG_THERMAL_DEBUGFS + struct thermal_debugfs *debugfs; +#endif }; /** From patchwork Wed Jun 1 15:14:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Lezcano X-Patchwork-Id: 578017 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 C7BEACCA478 for ; 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[176.182.171.101]) by smtp.gmail.com with ESMTPSA id y5-20020adff6c5000000b0020c5253d926sm1882077wrp.114.2022.06.01.08.14.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Jun 2022 08:15:00 -0700 (PDT) From: Daniel Lezcano To: daniel.lezcano@linaro.org, rafael@kernel.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_manafm@quicinc.com, Amit Kucheria , Zhang Rui Subject: [PATCH 3/3] thermal/sysfs: Remove cooling device sysfs statistics Date: Wed, 1 Jun 2022 17:14:41 +0200 Message-Id: <20220601151441.9128-3-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220601151441.9128-1-daniel.lezcano@linaro.org> References: <20220601151441.9128-1-daniel.lezcano@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The statistics are for debugging purpose and belong to debugfs rather than sysfs. As the previous changes introduced the same statistics in debugfs, those in sysfs are no longer needed and can be removed. That solves a couple of problems reported by different SoC vendors: - Extra memory used in low profile boards where the memory is limited resource - Truncated information and memory allocation failure with cooling devices having a large number of states Signed-off-by: Daniel Lezcano --- drivers/thermal/Kconfig | 7 - drivers/thermal/thermal_core.c | 2 - drivers/thermal/thermal_core.h | 10 -- drivers/thermal/thermal_helpers.c | 1 - drivers/thermal/thermal_sysfs.c | 217 ------------------------------ include/linux/thermal.h | 1 - 6 files changed, 238 deletions(-) diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 42400c6aed61..0c7b776462a9 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -26,13 +26,6 @@ config THERMAL_NETLINK trip point crossed, cooling device update or governor change. It is recommended to enable the feature. -config THERMAL_STATISTICS - bool "Thermal state transition statistics" - help - Export thermal state transition statistics information through sysfs. - - If in doubt, say N. - config THERMAL_DEBUGFS bool "Thermal debugging file system" depends on DEBUG_FS diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index a2d6eb0d0895..4851f2c7910f 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -949,7 +949,6 @@ __thermal_cooling_device_register(struct device_node *np, return cdev; out_kfree_type: - thermal_cooling_device_destroy_sysfs(cdev); kfree(cdev->type); put_device(&cdev->device); cdev = NULL; @@ -1117,7 +1116,6 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev) ida_simple_remove(&thermal_cdev_ida, cdev->id); device_del(&cdev->device); - thermal_cooling_device_destroy_sysfs(cdev); kfree(cdev->type); put_device(&cdev->device); } diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 49331b8a5404..dcae52f20258 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -134,22 +134,12 @@ void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms); int thermal_zone_create_device_groups(struct thermal_zone_device *, int); void thermal_zone_destroy_device_groups(struct thermal_zone_device *); void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *); -void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev); /* used only at binding time */ ssize_t trip_point_show(struct device *, struct device_attribute *, char *); ssize_t weight_show(struct device *, struct device_attribute *, char *); ssize_t weight_store(struct device *, struct device_attribute *, const char *, size_t); -#ifdef CONFIG_THERMAL_STATISTICS -void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, - unsigned long new_state); -#else -static inline void -thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, - unsigned long new_state) {} -#endif /* CONFIG_THERMAL_STATISTICS */ - /* device tree support */ #ifdef CONFIG_THERMAL_OF int of_parse_thermal_zones(void); diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c index 040d9e9b55e1..81185bb0d526 100644 --- a/drivers/thermal/thermal_helpers.c +++ b/drivers/thermal/thermal_helpers.c @@ -204,7 +204,6 @@ int thermal_cdev_set_state(struct thermal_cooling_device *cdev, int state) ret = cdev->ops->set_cur_state(cdev, state); if (!ret) { thermal_notify_cdev_state_update(cdev->id, state); - thermal_cooling_device_stats_update(cdev, state); thermal_debugfs_cdev_transition(cdev, state); } diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index 935e79909121..e48c5ad26611 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -641,231 +641,14 @@ static const struct attribute_group cooling_device_attr_group = { static const struct attribute_group *cooling_device_attr_groups[] = { &cooling_device_attr_group, - NULL, /* Space allocated for cooling_device_stats_attr_group */ NULL, }; -#ifdef CONFIG_THERMAL_STATISTICS -struct cooling_dev_stats { - spinlock_t lock; - unsigned int total_trans; - unsigned long state; - unsigned long max_states; - ktime_t last_time; - ktime_t *time_in_state; - unsigned int *trans_table; -}; - -static void update_time_in_state(struct cooling_dev_stats *stats) -{ - ktime_t now = ktime_get(), delta; - - delta = ktime_sub(now, stats->last_time); - stats->time_in_state[stats->state] = - ktime_add(stats->time_in_state[stats->state], delta); - stats->last_time = now; -} - -void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, - unsigned long new_state) -{ - struct cooling_dev_stats *stats = cdev->stats; - - if (!stats) - return; - - spin_lock(&stats->lock); - - if (stats->state == new_state) - goto unlock; - - update_time_in_state(stats); - stats->trans_table[stats->state * stats->max_states + new_state]++; - stats->state = new_state; - stats->total_trans++; - -unlock: - spin_unlock(&stats->lock); -} - -static ssize_t total_trans_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct thermal_cooling_device *cdev = to_cooling_device(dev); - struct cooling_dev_stats *stats = cdev->stats; - int ret; - - spin_lock(&stats->lock); - ret = sprintf(buf, "%u\n", stats->total_trans); - spin_unlock(&stats->lock); - - return ret; -} - -static ssize_t -time_in_state_ms_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct thermal_cooling_device *cdev = to_cooling_device(dev); - struct cooling_dev_stats *stats = cdev->stats; - ssize_t len = 0; - int i; - - spin_lock(&stats->lock); - update_time_in_state(stats); - - for (i = 0; i < stats->max_states; i++) { - len += sprintf(buf + len, "state%u\t%llu\n", i, - ktime_to_ms(stats->time_in_state[i])); - } - spin_unlock(&stats->lock); - - return len; -} - -static ssize_t -reset_store(struct device *dev, struct device_attribute *attr, const char *buf, - size_t count) -{ - struct thermal_cooling_device *cdev = to_cooling_device(dev); - struct cooling_dev_stats *stats = cdev->stats; - int i, states = stats->max_states; - - spin_lock(&stats->lock); - - stats->total_trans = 0; - stats->last_time = ktime_get(); - memset(stats->trans_table, 0, - states * states * sizeof(*stats->trans_table)); - - for (i = 0; i < stats->max_states; i++) - stats->time_in_state[i] = ktime_set(0, 0); - - spin_unlock(&stats->lock); - - return count; -} - -static ssize_t trans_table_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct thermal_cooling_device *cdev = to_cooling_device(dev); - struct cooling_dev_stats *stats = cdev->stats; - ssize_t len = 0; - int i, j; - - len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); - len += snprintf(buf + len, PAGE_SIZE - len, " : "); - for (i = 0; i < stats->max_states; i++) { - if (len >= PAGE_SIZE) - break; - len += snprintf(buf + len, PAGE_SIZE - len, "state%2u ", i); - } - if (len >= PAGE_SIZE) - return PAGE_SIZE; - - len += snprintf(buf + len, PAGE_SIZE - len, "\n"); - - for (i = 0; i < stats->max_states; i++) { - if (len >= PAGE_SIZE) - break; - - len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i); - - for (j = 0; j < stats->max_states; j++) { - if (len >= PAGE_SIZE) - break; - len += snprintf(buf + len, PAGE_SIZE - len, "%8u ", - stats->trans_table[i * stats->max_states + j]); - } - if (len >= PAGE_SIZE) - break; - len += snprintf(buf + len, PAGE_SIZE - len, "\n"); - } - - if (len >= PAGE_SIZE) { - pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n"); - return -EFBIG; - } - return len; -} - -static DEVICE_ATTR_RO(total_trans); -static DEVICE_ATTR_RO(time_in_state_ms); -static DEVICE_ATTR_WO(reset); -static DEVICE_ATTR_RO(trans_table); - -static struct attribute *cooling_device_stats_attrs[] = { - &dev_attr_total_trans.attr, - &dev_attr_time_in_state_ms.attr, - &dev_attr_reset.attr, - &dev_attr_trans_table.attr, - NULL -}; - -static const struct attribute_group cooling_device_stats_attr_group = { - .attrs = cooling_device_stats_attrs, - .name = "stats" -}; - -static void cooling_device_stats_setup(struct thermal_cooling_device *cdev) -{ - struct cooling_dev_stats *stats; - unsigned long states; - int var; - - if (cdev->ops->get_max_state(cdev, &states)) - return; - - states++; /* Total number of states is highest state + 1 */ - - var = sizeof(*stats); - var += sizeof(*stats->time_in_state) * states; - var += sizeof(*stats->trans_table) * states * states; - - stats = kzalloc(var, GFP_KERNEL); - if (!stats) - return; - - stats->time_in_state = (ktime_t *)(stats + 1); - stats->trans_table = (unsigned int *)(stats->time_in_state + states); - cdev->stats = stats; - stats->last_time = ktime_get(); - stats->max_states = states; - - spin_lock_init(&stats->lock); - - /* Fill the empty slot left in cooling_device_attr_groups */ - var = ARRAY_SIZE(cooling_device_attr_groups) - 2; - cooling_device_attr_groups[var] = &cooling_device_stats_attr_group; -} - -static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev) -{ - kfree(cdev->stats); - cdev->stats = NULL; -} - -#else - -static inline void -cooling_device_stats_setup(struct thermal_cooling_device *cdev) {} -static inline void -cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {} - -#endif /* CONFIG_THERMAL_STATISTICS */ - void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev) { - cooling_device_stats_setup(cdev); cdev->device.groups = cooling_device_attr_groups; } -void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev) -{ - cooling_device_stats_destroy(cdev); -} - /* these helper will be used only at the time of bindig */ ssize_t trip_point_show(struct device *dev, struct device_attribute *attr, char *buf) diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 4a69e8a6868e..522c9180a08d 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -96,7 +96,6 @@ struct thermal_cooling_device { struct device device; struct device_node *np; void *devdata; - void *stats; const struct thermal_cooling_device_ops *ops; bool updated; /* true if the cooling device does not need update */ struct mutex lock; /* protect thermal_instances list */