From c0e0421a60bf468e88cf569fbd727346b138ed04 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Mar 2023 17:52:33 +0100 Subject: ACPI: processor: Reorder acpi_processor_driver_init() The cpufreq policy notifier in the ACPI processor driver may as well be registered before the driver itself, which causes acpi_processor_cpufreq_init to be true (unless the notifier registration fails, which is unlikely at that point) when the ACPI CPU thermal cooling devices are registered, so the processor_get_max_state() result does not change while acpi_processor_driver_init() is running. Change the ordering in acpi_processor_driver_init() accordingly to prevent the max_state value from remaining 0 permanently for all ACPI CPU cooling devices due to setting acpi_processor_cpufreq_init too late. [Note that processor_get_max_state() may still return different values at different times after this change, depending on the cpufreq driver registration time, but that issue needs to be addressed separately.] Fixes: a365105c685c("thermal: sysfs: Reuse cdev->max_state") Reported-by: Wang, Quanxian Link: https://lore.kernel.org/linux-pm/53ec1f06f61c984100868926f282647e57ecfb2d.camel@intel.com Signed-off-by: Rafael J. Wysocki Tested-by: Zhang Rui Reviewed-by: Zhang Rui --- drivers/acpi/processor_driver.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index 1278969eec1f..4bd16b3f0781 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -263,6 +263,12 @@ static int __init acpi_processor_driver_init(void) if (acpi_disabled) return 0; + if (!cpufreq_register_notifier(&acpi_processor_notifier_block, + CPUFREQ_POLICY_NOTIFIER)) { + acpi_processor_cpufreq_init = true; + acpi_processor_ignore_ppc_init(); + } + result = driver_register(&acpi_processor_driver); if (result < 0) return result; @@ -276,12 +282,6 @@ static int __init acpi_processor_driver_init(void) cpuhp_setup_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD, "acpi/cpu-drv:dead", NULL, acpi_soft_cpu_dead); - if (!cpufreq_register_notifier(&acpi_processor_notifier_block, - CPUFREQ_POLICY_NOTIFIER)) { - acpi_processor_cpufreq_init = true; - acpi_processor_ignore_ppc_init(); - } - acpi_processor_throttling_init(); return 0; err: -- cgit v1.2.3-70-g09d2 From c43198af05cffa5de8d4f356c40ce4bdca066272 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Mar 2023 17:54:34 +0100 Subject: thermal: core: Introduce thermal_cooling_device_present() Introduce a helper function, thermal_cooling_device_present(), for checking if the given cooling device is in the list of registered cooling devices to avoid some code duplication in a subsequent patch. No expected functional impact. Signed-off-by: Rafael J. Wysocki Tested-by: Zhang Rui Reviewed-by: Zhang Rui --- drivers/thermal/thermal_core.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 55679fd86505..8894342540f1 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1045,6 +1045,18 @@ devm_thermal_of_cooling_device_register(struct device *dev, } EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register); +static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev) +{ + struct thermal_cooling_device *pos = NULL; + + list_for_each_entry(pos, &thermal_cdev_list, node) { + if (pos == cdev) + return true; + } + + return false; +} + static void __unbind(struct thermal_zone_device *tz, int mask, struct thermal_cooling_device *cdev) { @@ -1067,20 +1079,17 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev) int i; const struct thermal_zone_params *tzp; struct thermal_zone_device *tz; - struct thermal_cooling_device *pos = NULL; if (!cdev) return; mutex_lock(&thermal_list_lock); - list_for_each_entry(pos, &thermal_cdev_list, node) - if (pos == cdev) - break; - if (pos != cdev) { - /* thermal cooling device not found */ + + if (!thermal_cooling_device_present(cdev)) { mutex_unlock(&thermal_list_lock); return; } + list_del(&cdev->node); /* Unbind all thermal zones associated with 'this' cdev */ -- cgit v1.2.3-70-g09d2 From 790930f44289c8209c57461b2db499fcc702e0b3 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Mar 2023 18:01:26 +0100 Subject: thermal: core: Introduce thermal_cooling_device_update() Introduce a core thermal API function, thermal_cooling_device_update(), for updating the max_state value for a cooling device and rearranging its statistics in sysfs after a possible change of its ->get_max_state() callback return value. That callback is now invoked only once, during cooling device registration, to populate the max_state field in the cooling device object, so if its return value changes, it needs to be invoked again and the new return value needs to be stored as max_state. Moreover, the statistics presented in sysfs need to be rearranged in general, because there may not be enough room in them to store data for all of the possible states (in the case when max_state grows). The new function takes care of that (and some other minor things related to it), but some extra locking and lockdep annotations are added in several places too to protect against crashes in the cases when the statistics are not present or when a stale max_state value might be used by sysfs attributes. Note that the actual user of the new function will be added separately. Link: https://lore.kernel.org/linux-pm/53ec1f06f61c984100868926f282647e57ecfb2d.camel@intel.com/ Signed-off-by: Rafael J. Wysocki Tested-by: Zhang Rui Reviewed-by: Zhang Rui --- drivers/thermal/thermal_core.c | 83 ++++++++++++++++++++++++++++++++++++++++- drivers/thermal/thermal_core.h | 2 + drivers/thermal/thermal_sysfs.c | 74 +++++++++++++++++++++++++++++++----- include/linux/thermal.h | 1 + 4 files changed, 150 insertions(+), 10 deletions(-) (limited to 'drivers') diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 8894342540f1..cfd4c1afeae7 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -613,6 +613,7 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz, struct thermal_instance *pos; struct thermal_zone_device *pos1; struct thermal_cooling_device *pos2; + bool upper_no_limit; int result; if (trip >= tz->num_trips || trip < 0) @@ -632,7 +633,13 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz, /* lower default 0, upper default max_state */ lower = lower == THERMAL_NO_LIMIT ? 0 : lower; - upper = upper == THERMAL_NO_LIMIT ? cdev->max_state : upper; + + if (upper == THERMAL_NO_LIMIT) { + upper = cdev->max_state; + upper_no_limit = true; + } else { + upper_no_limit = false; + } if (lower > upper || upper > cdev->max_state) return -EINVAL; @@ -644,6 +651,7 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz, dev->cdev = cdev; dev->trip = trip; dev->upper = upper; + dev->upper_no_limit = upper_no_limit; dev->lower = lower; dev->target = THERMAL_NO_TARGET; dev->weight = weight; @@ -1057,6 +1065,79 @@ static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev) return false; } +/** + * thermal_cooling_device_update - Update a cooling device object + * @cdev: Target cooling device. + * + * Update @cdev to reflect a change of the underlying hardware or platform. + * + * Must be called when the maximum cooling state of @cdev becomes invalid and so + * its .get_max_state() callback needs to be run to produce the new maximum + * cooling state value. + */ +void thermal_cooling_device_update(struct thermal_cooling_device *cdev) +{ + struct thermal_instance *ti; + unsigned long state; + + if (IS_ERR_OR_NULL(cdev)) + return; + + /* + * Hold thermal_list_lock throughout the update to prevent the device + * from going away while being updated. + */ + mutex_lock(&thermal_list_lock); + + if (!thermal_cooling_device_present(cdev)) + goto unlock_list; + + /* + * Update under the cdev lock to prevent the state from being set beyond + * the new limit concurrently. + */ + mutex_lock(&cdev->lock); + + if (cdev->ops->get_max_state(cdev, &cdev->max_state)) + goto unlock; + + thermal_cooling_device_stats_reinit(cdev); + + list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) { + if (ti->upper == cdev->max_state) + continue; + + if (ti->upper < cdev->max_state) { + if (ti->upper_no_limit) + ti->upper = cdev->max_state; + + continue; + } + + ti->upper = cdev->max_state; + if (ti->lower > ti->upper) + ti->lower = ti->upper; + + if (ti->target == THERMAL_NO_TARGET) + continue; + + if (ti->target > ti->upper) + ti->target = ti->upper; + } + + if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state) + goto unlock; + + thermal_cooling_device_stats_update(cdev, state); + +unlock: + mutex_unlock(&cdev->lock); + +unlock_list: + mutex_unlock(&thermal_list_lock); +} +EXPORT_SYMBOL_GPL(thermal_cooling_device_update); + static void __unbind(struct thermal_zone_device *tz, int mask, struct thermal_cooling_device *cdev) { diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 7af54382e915..3d4a787c6b28 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -101,6 +101,7 @@ struct thermal_instance { struct list_head tz_node; /* node in tz->thermal_instances */ struct list_head cdev_node; /* node in cdev->thermal_instances */ unsigned int weight; /* The weight of the cooling device */ + bool upper_no_limit; }; #define to_thermal_zone(_dev) \ @@ -127,6 +128,7 @@ 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); +void thermal_cooling_device_stats_reinit(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 *); diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index cef860deaf91..a4aba7b8bb8b 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -685,6 +685,8 @@ void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, { struct cooling_dev_stats *stats = cdev->stats; + lockdep_assert_held(&cdev->lock); + if (!stats) return; @@ -706,13 +708,22 @@ 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; + struct cooling_dev_stats *stats; + int ret = 0; + + mutex_lock(&cdev->lock); + + stats = cdev->stats; + if (!stats) + goto unlock; spin_lock(&stats->lock); ret = sprintf(buf, "%u\n", stats->total_trans); spin_unlock(&stats->lock); +unlock: + mutex_unlock(&cdev->lock); + return ret; } @@ -721,11 +732,18 @@ 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; + struct cooling_dev_stats *stats; ssize_t len = 0; int i; + mutex_lock(&cdev->lock); + + stats = cdev->stats; + if (!stats) + goto unlock; + spin_lock(&stats->lock); + update_time_in_state(stats); for (i = 0; i <= cdev->max_state; i++) { @@ -734,6 +752,9 @@ time_in_state_ms_show(struct device *dev, struct device_attribute *attr, } spin_unlock(&stats->lock); +unlock: + mutex_unlock(&cdev->lock); + return len; } @@ -742,8 +763,16 @@ 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 = cdev->max_state + 1; + struct cooling_dev_stats *stats; + int i, states; + + mutex_lock(&cdev->lock); + + stats = cdev->stats; + if (!stats) + goto unlock; + + states = cdev->max_state + 1; spin_lock(&stats->lock); @@ -757,6 +786,9 @@ reset_store(struct device *dev, struct device_attribute *attr, const char *buf, spin_unlock(&stats->lock); +unlock: + mutex_unlock(&cdev->lock); + return count; } @@ -764,10 +796,18 @@ 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; + struct cooling_dev_stats *stats; ssize_t len = 0; int i, j; + mutex_lock(&cdev->lock); + + stats = cdev->stats; + if (!stats) { + len = -ENODATA; + goto unlock; + } + len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); len += snprintf(buf + len, PAGE_SIZE - len, " : "); for (i = 0; i <= cdev->max_state; i++) { @@ -775,8 +815,10 @@ static ssize_t trans_table_show(struct device *dev, break; len += snprintf(buf + len, PAGE_SIZE - len, "state%2u ", i); } - if (len >= PAGE_SIZE) - return PAGE_SIZE; + if (len >= PAGE_SIZE) { + len = PAGE_SIZE; + goto unlock; + } len += snprintf(buf + len, PAGE_SIZE - len, "\n"); @@ -799,8 +841,12 @@ static ssize_t trans_table_show(struct device *dev, if (len >= PAGE_SIZE) { pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n"); - return -EFBIG; + len = -EFBIG; } + +unlock: + mutex_unlock(&cdev->lock); + return len; } @@ -830,6 +876,8 @@ static void cooling_device_stats_setup(struct thermal_cooling_device *cdev) unsigned long states = cdev->max_state + 1; int var; + lockdep_assert_held(&cdev->lock); + var = sizeof(*stats); var += sizeof(*stats->time_in_state) * states; var += sizeof(*stats->trans_table) * states * states; @@ -855,6 +903,8 @@ out: static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev) { + lockdep_assert_held(&cdev->lock); + kfree(cdev->stats); cdev->stats = NULL; } @@ -879,6 +929,12 @@ void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev) cooling_device_stats_destroy(cdev); } +void thermal_cooling_device_stats_reinit(struct thermal_cooling_device *cdev) +{ + cooling_device_stats_destroy(cdev); + cooling_device_stats_setup(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 2bb4bf33f4f3..13c6aaed18df 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -384,6 +384,7 @@ devm_thermal_of_cooling_device_register(struct device *dev, struct device_node *np, char *type, void *devdata, const struct thermal_cooling_device_ops *ops); +void thermal_cooling_device_update(struct thermal_cooling_device *); void thermal_cooling_device_unregister(struct thermal_cooling_device *); struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name); int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp); -- cgit v1.2.3-70-g09d2 From 22c52fa5155a2f48aedb0f675903b20457285a27 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Mar 2023 18:03:40 +0100 Subject: ACPI: processor: thermal: Update CPU cooling devices on cpufreq policy changes When a cpufreq policy appears or goes away, the CPU cooling devices for the CPUs covered by that policy need to be updated so that the new processor_get_max_state() value is stored as max_state and the statistics in sysfs are rearranged for each of them. Do that accordingly in acpi_thermal_cpufreq_init() and acpi_thermal_cpufreq_exit(). Fixes: a365105c685c("thermal: sysfs: Reuse cdev->max_state") Reported-by: Wang, Quanxian Link: https://lore.kernel.org/linux-pm/53ec1f06f61c984100868926f282647e57ecfb2d.camel@intel.com Signed-off-by: Rafael J. Wysocki Tested-by: Zhang Rui Reviewed-by: Zhang Rui --- drivers/acpi/processor_thermal.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c index e534fd49a67e..b7c6287eccca 100644 --- a/drivers/acpi/processor_thermal.c +++ b/drivers/acpi/processor_thermal.c @@ -140,9 +140,13 @@ void acpi_thermal_cpufreq_init(struct cpufreq_policy *policy) ret = freq_qos_add_request(&policy->constraints, &pr->thermal_req, FREQ_QOS_MAX, INT_MAX); - if (ret < 0) + if (ret < 0) { pr_err("Failed to add freq constraint for CPU%d (%d)\n", cpu, ret); + continue; + } + + thermal_cooling_device_update(pr->cdev); } } @@ -153,8 +157,12 @@ void acpi_thermal_cpufreq_exit(struct cpufreq_policy *policy) for_each_cpu(cpu, policy->related_cpus) { struct acpi_processor *pr = per_cpu(processors, cpu); - if (pr) - freq_qos_remove_request(&pr->thermal_req); + if (!pr) + continue; + + freq_qos_remove_request(&pr->thermal_req); + + thermal_cooling_device_update(pr->cdev); } } #else /* ! CONFIG_CPU_FREQ */ -- cgit v1.2.3-70-g09d2