From 34896620422eefe1bad998ed4b48117426ad81f9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:52:35 +0100 Subject: [PATCH 01/30] PM: QoS: Drop debugfs interface After commit c3082a674f46 ("PM: QoS: Get rid of unused flags") the only global PM QoS class in use is PM_QOS_CPU_DMA_LATENCY and the existing PM QoS debugfs interface has become overly complicated (as it takes other potentially possible PM QoS classes that are not there any more into account). It is also not particularly useful (the "type" of the PM_QOS_CPU_DMA_LATENCY is known, its aggregate value can be read from /dev/cpu_dma_latency and the number of requests in the queue does not really matter) and there are no known users depending on it. Moreover, there are dedicated trace events that can be used for tracking PM QoS usage with much higher precision. For these reasons, drop the PM QoS debugfs interface altogether. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson --- kernel/power/qos.c | 73 ++-------------------------------------------- 1 file changed, 2 insertions(+), 71 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 83edf8698118..d932fa42e8e4 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -137,69 +137,6 @@ static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) c->target_value = value; } -static int pm_qos_debug_show(struct seq_file *s, void *unused) -{ - struct pm_qos_object *qos = (struct pm_qos_object *)s->private; - struct pm_qos_constraints *c; - struct pm_qos_request *req; - char *type; - unsigned long flags; - int tot_reqs = 0; - int active_reqs = 0; - - if (IS_ERR_OR_NULL(qos)) { - pr_err("%s: bad qos param!\n", __func__); - return -EINVAL; - } - c = qos->constraints; - if (IS_ERR_OR_NULL(c)) { - pr_err("%s: Bad constraints on qos?\n", __func__); - return -EINVAL; - } - - /* Lock to ensure we have a snapshot */ - spin_lock_irqsave(&pm_qos_lock, flags); - if (plist_head_empty(&c->list)) { - seq_puts(s, "Empty!\n"); - goto out; - } - - switch (c->type) { - case PM_QOS_MIN: - type = "Minimum"; - break; - case PM_QOS_MAX: - type = "Maximum"; - break; - case PM_QOS_SUM: - type = "Sum"; - break; - default: - type = "Unknown"; - } - - plist_for_each_entry(req, &c->list, node) { - char *state = "Default"; - - if ((req->node).prio != c->default_value) { - active_reqs++; - state = "Active"; - } - tot_reqs++; - seq_printf(s, "%d: %d: %s\n", tot_reqs, - (req->node).prio, state); - } - - seq_printf(s, "Type=%s, Value=%d, Requests: active=%d / total=%d\n", - type, pm_qos_get_value(c), active_reqs, tot_reqs); - -out: - spin_unlock_irqrestore(&pm_qos_lock, flags); - return 0; -} - -DEFINE_SHOW_ATTRIBUTE(pm_qos_debug); - /** * pm_qos_update_target - manages the constraints list and calls the notifiers * if needed @@ -529,15 +466,12 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); /* User space interface to PM QoS classes via misc devices */ -static int register_pm_qos_misc(struct pm_qos_object *qos, struct dentry *d) +static int register_pm_qos_misc(struct pm_qos_object *qos) { qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; qos->pm_qos_power_miscdev.name = qos->name; qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; - debugfs_create_file(qos->name, S_IRUGO, d, (void *)qos, - &pm_qos_debug_fops); - return misc_register(&qos->pm_qos_power_miscdev); } @@ -631,14 +565,11 @@ static int __init pm_qos_power_init(void) { int ret = 0; int i; - struct dentry *d; BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES); - d = debugfs_create_dir("pm_qos", NULL); - for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) { - ret = register_pm_qos_misc(pm_qos_array[i], d); + ret = register_pm_qos_misc(pm_qos_array[i]); if (ret < 0) { pr_err("%s: %s setup failed\n", __func__, pm_qos_array[i]->name); From 5a7ea52b6faec6f8877e49645a80349b2d970f0a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:58:17 +0100 Subject: [PATCH 02/30] PM: QoS: Drop pm_qos_update_request_timeout() The pm_qos_update_request_timeout() function is not called from anywhere, so drop it along with the work member in struct pm_qos_request needed by it. Also drop the useless pm_qos_update_request_timeout trace event that is only triggered by that function (so it never triggers at all) and update the trace events documentation accordingly. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- Documentation/trace/events-power.rst | 2 -- include/linux/pm_qos.h | 4 --- include/trace/events/power.h | 24 -------------- kernel/power/qos.c | 48 ---------------------------- 4 files changed, 78 deletions(-) diff --git a/Documentation/trace/events-power.rst b/Documentation/trace/events-power.rst index 2ef318962e29..eec7453a168e 100644 --- a/Documentation/trace/events-power.rst +++ b/Documentation/trace/events-power.rst @@ -78,11 +78,9 @@ target/flags update. pm_qos_add_request "pm_qos_class=%s value=%d" pm_qos_update_request "pm_qos_class=%s value=%d" pm_qos_remove_request "pm_qos_class=%s value=%d" - pm_qos_update_request_timeout "pm_qos_class=%s value=%d, timeout_us=%ld" The first parameter gives the QoS class name (e.g. "CPU_DMA_LATENCY"). The second parameter is value to be added/updated/removed. -The third parameter is timeout value in usec. :: pm_qos_update_target "action=%s prev_value=%d curr_value=%d" diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 19eafca5680e..4747bdb6bed2 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -8,7 +8,6 @@ #include #include #include -#include enum { PM_QOS_RESERVED = 0, @@ -43,7 +42,6 @@ enum pm_qos_flags_status { struct pm_qos_request { struct plist_node node; int pm_qos_class; - struct delayed_work work; /* for pm_qos_update_request_timeout */ }; struct pm_qos_flags_request { @@ -149,8 +147,6 @@ void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value); void pm_qos_update_request(struct pm_qos_request *req, s32 new_value); -void pm_qos_update_request_timeout(struct pm_qos_request *req, - s32 new_value, unsigned long timeout_us); void pm_qos_remove_request(struct pm_qos_request *req); int pm_qos_request(int pm_qos_class); diff --git a/include/trace/events/power.h b/include/trace/events/power.h index 7457e238e1b7..ecf39daabf16 100644 --- a/include/trace/events/power.h +++ b/include/trace/events/power.h @@ -404,30 +404,6 @@ DEFINE_EVENT(pm_qos_request, pm_qos_remove_request, TP_ARGS(pm_qos_class, value) ); -TRACE_EVENT(pm_qos_update_request_timeout, - - TP_PROTO(int pm_qos_class, s32 value, unsigned long timeout_us), - - TP_ARGS(pm_qos_class, value, timeout_us), - - TP_STRUCT__entry( - __field( int, pm_qos_class ) - __field( s32, value ) - __field( unsigned long, timeout_us ) - ), - - TP_fast_assign( - __entry->pm_qos_class = pm_qos_class; - __entry->value = value; - __entry->timeout_us = timeout_us; - ), - - TP_printk("pm_qos_class=%s value=%d, timeout_us=%ld", - __print_symbolic(__entry->pm_qos_class, - { PM_QOS_CPU_DMA_LATENCY, "CPU_DMA_LATENCY" }), - __entry->value, __entry->timeout_us) -); - DECLARE_EVENT_CLASS(pm_qos_update, TP_PROTO(enum pm_qos_req_action action, int prev_value, int curr_value), diff --git a/kernel/power/qos.c b/kernel/power/qos.c index d932fa42e8e4..67dab7f330e4 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -295,21 +295,6 @@ static void __pm_qos_update_request(struct pm_qos_request *req, &req->node, PM_QOS_UPDATE_REQ, new_value); } -/** - * pm_qos_work_fn - the timeout handler of pm_qos_update_request_timeout - * @work: work struct for the delayed work (timeout) - * - * This cancels the timeout request by falling back to the default at timeout. - */ -static void pm_qos_work_fn(struct work_struct *work) -{ - struct pm_qos_request *req = container_of(to_delayed_work(work), - struct pm_qos_request, - work); - - __pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE); -} - /** * pm_qos_add_request - inserts new qos request into the list * @req: pointer to a preallocated handle @@ -334,7 +319,6 @@ void pm_qos_add_request(struct pm_qos_request *req, return; } req->pm_qos_class = pm_qos_class; - INIT_DELAYED_WORK(&req->work, pm_qos_work_fn); trace_pm_qos_add_request(pm_qos_class, value); pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints, &req->node, PM_QOS_ADD_REQ, value); @@ -362,40 +346,10 @@ void pm_qos_update_request(struct pm_qos_request *req, return; } - cancel_delayed_work_sync(&req->work); __pm_qos_update_request(req, new_value); } EXPORT_SYMBOL_GPL(pm_qos_update_request); -/** - * pm_qos_update_request_timeout - modifies an existing qos request temporarily. - * @req : handle to list element holding a pm_qos request to use - * @new_value: defines the temporal qos request - * @timeout_us: the effective duration of this qos request in usecs. - * - * After timeout_us, this qos request is cancelled automatically. - */ -void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value, - unsigned long timeout_us) -{ - if (!req) - return; - if (WARN(!pm_qos_request_active(req), - "%s called for unknown object.", __func__)) - return; - - cancel_delayed_work_sync(&req->work); - - trace_pm_qos_update_request_timeout(req->pm_qos_class, - new_value, timeout_us); - if (new_value != req->node.prio) - pm_qos_update_target( - pm_qos_array[req->pm_qos_class]->constraints, - &req->node, PM_QOS_UPDATE_REQ, new_value); - - schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us)); -} - /** * pm_qos_remove_request - modifies an existing qos request * @req: handle to request list element @@ -415,8 +369,6 @@ void pm_qos_remove_request(struct pm_qos_request *req) return; } - cancel_delayed_work_sync(&req->work); - trace_pm_qos_remove_request(req->pm_qos_class, PM_QOS_DEFAULT_VALUE); pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints, &req->node, PM_QOS_REMOVE_REQ, From 87ad7356799622b69478076cd99df7a5024992cb Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:58:26 +0100 Subject: [PATCH 03/30] PM: QoS: Drop the PM_QOS_SUM QoS type The PM_QOS_SUM QoS type is not used, so drop it along with the code referring to it in pm_qos_get_value() and the related local variables in there. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 1 - kernel/power/qos.c | 9 --------- 2 files changed, 10 deletions(-) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 4747bdb6bed2..48bfb96a9360 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -53,7 +53,6 @@ enum pm_qos_type { PM_QOS_UNITIALIZED, PM_QOS_MAX, /* return the largest value */ PM_QOS_MIN, /* return the smallest value */ - PM_QOS_SUM /* return the sum */ }; /* diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 67dab7f330e4..a6be7faa1974 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -101,9 +101,6 @@ static const struct file_operations pm_qos_power_fops = { /* unlocked internal variant */ static inline int pm_qos_get_value(struct pm_qos_constraints *c) { - struct plist_node *node; - int total_value = 0; - if (plist_head_empty(&c->list)) return c->no_constraint_value; @@ -114,12 +111,6 @@ static inline int pm_qos_get_value(struct pm_qos_constraints *c) case PM_QOS_MAX: return plist_last(&c->list)->prio; - case PM_QOS_SUM: - plist_for_each(node, &c->list) - total_value += node->prio; - - return total_value; - default: /* runtime check for not using enum */ BUG(); From 7b35370b2ebc2608ba0f2e0ecb996fa7f38e9731 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:58:33 +0100 Subject: [PATCH 04/30] PM: QoS: Clean up pm_qos_update_target() and pm_qos_update_flags() Clean up the pm_qos_update_target() function: * Update its kerneldoc comment. * Drop the redundant ret local variable from it. * Reorder definitions of local variables in it. * Update a comment in it. Also update the kerneldoc comment of pm_qos_update_flags() (e.g. notifiers are not called by it any more) and add one emtpy line to its body (for more visual clarity). No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- kernel/power/qos.c | 56 ++++++++++++++++++++++++---------------------- 1 file changed, 29 insertions(+), 27 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index a6be7faa1974..6a36809d6160 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -129,24 +129,30 @@ static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) } /** - * pm_qos_update_target - manages the constraints list and calls the notifiers - * if needed - * @c: constraints data struct - * @node: request to add to the list, to update or to remove - * @action: action to take on the constraints list - * @value: value of the request to add or update + * pm_qos_update_target - Update a list of PM QoS constraint requests. + * @c: List of PM QoS requests. + * @node: Target list entry. + * @action: Action to carry out (add, update or remove). + * @value: New request value for the target list entry. * - * This function returns 1 if the aggregated constraint value has changed, 0 - * otherwise. + * Update the given list of PM QoS constraint requests, @c, by carrying an + * @action involving the @node list entry and @value on it. + * + * The recognized values of @action are PM_QOS_ADD_REQ (store @value in @node + * and add it to the list), PM_QOS_UPDATE_REQ (remove @node from the list, store + * @value in it and add it to the list again), and PM_QOS_REMOVE_REQ (remove + * @node from the list, ignore @value). + * + * Return: 1 if the aggregate constraint value has changed, 0 otherwise. */ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, enum pm_qos_req_action action, int value) { - unsigned long flags; int prev_value, curr_value, new_value; - int ret; + unsigned long flags; spin_lock_irqsave(&pm_qos_lock, flags); + prev_value = pm_qos_get_value(c); if (value == PM_QOS_DEFAULT_VALUE) new_value = c->default_value; @@ -159,9 +165,8 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, break; case PM_QOS_UPDATE_REQ: /* - * to change the list, we atomically remove, reinit - * with new value and add, then see if the extremal - * changed + * To change the list, atomically remove, reinit with new value + * and add, then see if the aggregate has changed. */ plist_del(node, &c->list); /* fall through */ @@ -180,16 +185,14 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, spin_unlock_irqrestore(&pm_qos_lock, flags); trace_pm_qos_update_target(action, prev_value, curr_value); - if (prev_value != curr_value) { - ret = 1; - if (c->notifiers) - blocking_notifier_call_chain(c->notifiers, - (unsigned long)curr_value, - NULL); - } else { - ret = 0; - } - return ret; + + if (prev_value == curr_value) + return 0; + + if (c->notifiers) + blocking_notifier_call_chain(c->notifiers, curr_value, NULL); + + return 1; } /** @@ -211,14 +214,12 @@ static void pm_qos_flags_remove_req(struct pm_qos_flags *pqf, /** * pm_qos_update_flags - Update a set of PM QoS flags. - * @pqf: Set of flags to update. + * @pqf: Set of PM QoS flags to update. * @req: Request to add to the set, to modify, or to remove from the set. * @action: Action to take on the set. * @val: Value of the request to add or modify. * - * Update the given set of PM QoS flags and call notifiers if the aggregate - * value has changed. Returns 1 if the aggregate constraint value has changed, - * 0 otherwise. + * Return: 1 if the aggregate constraint value has changed, 0 otherwise. */ bool pm_qos_update_flags(struct pm_qos_flags *pqf, struct pm_qos_flags_request *req, @@ -254,6 +255,7 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, spin_unlock_irqrestore(&pm_qos_lock, irqflags); trace_pm_qos_update_flags(action, prev_value, curr_value); + return prev_value != curr_value; } From dcd70ca1a3bf33aa5cf53aa6f72b8e51afb1ac48 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:58:39 +0100 Subject: [PATCH 05/30] PM: QoS: Clean up pm_qos_read_value() and pm_qos_get/set_value() Move the definition of pm_qos_read_value() before the one of pm_qos_get_value() and add a kerneldoc comment to it (as it is not static). Also replace the BUG() in pm_qos_get_value() with WARN() (to prevent the kernel from crashing if an unknown PM QoS type is used by mistake) and drop the comment next to it that is not necessary any more. Additionally, drop the unnecessary inline modifier from the header of pm_qos_set_value(). Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- kernel/power/qos.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 6a36809d6160..f09eca5ffe07 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -98,8 +98,16 @@ static const struct file_operations pm_qos_power_fops = { .llseek = noop_llseek, }; -/* unlocked internal variant */ -static inline int pm_qos_get_value(struct pm_qos_constraints *c) +/** + * pm_qos_read_value - Return the current effective constraint value. + * @c: List of PM QoS constraint requests. + */ +s32 pm_qos_read_value(struct pm_qos_constraints *c) +{ + return c->target_value; +} + +static int pm_qos_get_value(struct pm_qos_constraints *c) { if (plist_head_empty(&c->list)) return c->no_constraint_value; @@ -112,18 +120,12 @@ static inline int pm_qos_get_value(struct pm_qos_constraints *c) return plist_last(&c->list)->prio; default: - /* runtime check for not using enum */ - BUG(); + WARN(1, "Unknown PM QoS type in %s\n", __func__); return PM_QOS_DEFAULT_VALUE; } } -s32 pm_qos_read_value(struct pm_qos_constraints *c) -{ - return c->target_value; -} - -static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) +static void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) { c->target_value = value; } From 63cffc05348ea1fe65aa99e80ed330e33bf54220 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 23:59:22 +0100 Subject: [PATCH 06/30] PM: QoS: Drop iterations over global QoS classes After commit c3082a674f46 ("PM: QoS: Get rid of unused flags") the only global PM QoS class in use is PM_QOS_CPU_DMA_LATENCY, so it does not really make sense to iterate over global QoS classes anywhere, since there is only one. Remove iterations over global QoS classes from the code and use PM_QOS_CPU_DMA_LATENCY as the target class directly where needed. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- kernel/power/qos.c | 52 +++++++++++++--------------------------------- 1 file changed, 14 insertions(+), 38 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index f09eca5ffe07..57ff542a4f9d 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -412,7 +412,8 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) } EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); -/* User space interface to PM QoS classes via misc devices */ +/* User space interface to global PM QoS via misc device. */ + static int register_pm_qos_misc(struct pm_qos_object *qos) { qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; @@ -422,35 +423,18 @@ static int register_pm_qos_misc(struct pm_qos_object *qos) return misc_register(&qos->pm_qos_power_miscdev); } -static int find_pm_qos_object_by_minor(int minor) -{ - int pm_qos_class; - - for (pm_qos_class = PM_QOS_CPU_DMA_LATENCY; - pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { - if (minor == - pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) - return pm_qos_class; - } - return -1; -} - static int pm_qos_power_open(struct inode *inode, struct file *filp) { - long pm_qos_class; + struct pm_qos_request *req; - pm_qos_class = find_pm_qos_object_by_minor(iminor(inode)); - if (pm_qos_class >= PM_QOS_CPU_DMA_LATENCY) { - struct pm_qos_request *req = kzalloc(sizeof(*req), GFP_KERNEL); - if (!req) - return -ENOMEM; + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; - pm_qos_add_request(req, pm_qos_class, PM_QOS_DEFAULT_VALUE); - filp->private_data = req; + pm_qos_add_request(req, PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); + filp->private_data = req; - return 0; - } - return -EPERM; + return 0; } static int pm_qos_power_release(struct inode *inode, struct file *filp) @@ -464,7 +448,6 @@ static int pm_qos_power_release(struct inode *inode, struct file *filp) return 0; } - static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos) { @@ -507,26 +490,19 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, return count; } - static int __init pm_qos_power_init(void) { - int ret = 0; - int i; + int ret; BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES); - for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) { - ret = register_pm_qos_misc(pm_qos_array[i]); - if (ret < 0) { - pr_err("%s: %s setup failed\n", - __func__, pm_qos_array[i]->name); - return ret; - } - } + ret = register_pm_qos_misc(pm_qos_array[PM_QOS_CPU_DMA_LATENCY]); + if (ret < 0) + pr_err("%s: %s setup failed\n", __func__, + pm_qos_array[PM_QOS_CPU_DMA_LATENCY]->name); return ret; } - late_initcall(pm_qos_power_init); /* Definitions related to the frequency QoS below. */ From 299a229830a29a2d691ac17b27964c7d820f16a6 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:00:12 +0100 Subject: [PATCH 07/30] PM: QoS: Clean up misc device file operations Reorder the code to avoid using extra function header declarations for the pm_qos_power_*() family of functions and drop those declarations. Also clean up the internals of those functions to consolidate checks, avoid using redundant local variables and similar. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- kernel/power/qos.c | 62 +++++++++++++++++++--------------------------- 1 file changed, 26 insertions(+), 36 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 57ff542a4f9d..9f67584d4466 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -83,21 +83,6 @@ static struct pm_qos_object *pm_qos_array[] = { &cpu_dma_pm_qos, }; -static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, - size_t count, loff_t *f_pos); -static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, - size_t count, loff_t *f_pos); -static int pm_qos_power_open(struct inode *inode, struct file *filp); -static int pm_qos_power_release(struct inode *inode, struct file *filp); - -static const struct file_operations pm_qos_power_fops = { - .write = pm_qos_power_write, - .read = pm_qos_power_read, - .open = pm_qos_power_open, - .release = pm_qos_power_release, - .llseek = noop_llseek, -}; - /** * pm_qos_read_value - Return the current effective constraint value. * @c: List of PM QoS constraint requests. @@ -414,15 +399,6 @@ EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); /* User space interface to global PM QoS via misc device. */ -static int register_pm_qos_misc(struct pm_qos_object *qos) -{ - qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; - qos->pm_qos_power_miscdev.name = qos->name; - qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; - - return misc_register(&qos->pm_qos_power_miscdev); -} - static int pm_qos_power_open(struct inode *inode, struct file *filp) { struct pm_qos_request *req; @@ -439,9 +415,10 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp) static int pm_qos_power_release(struct inode *inode, struct file *filp) { - struct pm_qos_request *req; + struct pm_qos_request *req = filp->private_data; + + filp->private_data = NULL; - req = filp->private_data; pm_qos_remove_request(req); kfree(req); @@ -449,15 +426,13 @@ static int pm_qos_power_release(struct inode *inode, struct file *filp) } static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, - size_t count, loff_t *f_pos) + size_t count, loff_t *f_pos) { - s32 value; - unsigned long flags; struct pm_qos_request *req = filp->private_data; + unsigned long flags; + s32 value; - if (!req) - return -EINVAL; - if (!pm_qos_request_active(req)) + if (!req || !pm_qos_request_active(req)) return -EINVAL; spin_lock_irqsave(&pm_qos_lock, flags); @@ -468,10 +443,9 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, } static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, - size_t count, loff_t *f_pos) + size_t count, loff_t *f_pos) { s32 value; - struct pm_qos_request *req; if (count == sizeof(s32)) { if (copy_from_user(&value, buf, sizeof(s32))) @@ -484,12 +458,28 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, return ret; } - req = filp->private_data; - pm_qos_update_request(req, value); + pm_qos_update_request(filp->private_data, value); return count; } +static const struct file_operations pm_qos_power_fops = { + .write = pm_qos_power_write, + .read = pm_qos_power_read, + .open = pm_qos_power_open, + .release = pm_qos_power_release, + .llseek = noop_llseek, +}; + +static int register_pm_qos_misc(struct pm_qos_object *qos) +{ + qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; + qos->pm_qos_power_miscdev.name = qos->name; + qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; + + return misc_register(&qos->pm_qos_power_miscdev); +} + static int __init pm_qos_power_init(void) { int ret; From 02c92a378940ba1a46b6b7ad277f1b07f8093dbc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:01:18 +0100 Subject: [PATCH 08/30] PM: QoS: Redefine struct pm_qos_request and drop struct pm_qos_object First, change the definition of struct pm_qos_request so that it contains a struct pm_qos_constraints pointer (called "qos") instead of a PM QoS class number (in preparation for dropping the PM QoS classes concept altogether going forward) and move its definition (along with the definition of struct pm_qos_flags_request that does not change) after the definition of struct pm_qos_constraints. Next, drop the definition of struct pm_qos_object and the null_pm_qos and cpu_dma_pm_qos variables of that type along with pm_qos_array[] holding pointers to them and change the code to refer to the pm_qos_constraints structure directly or to use the new qos pointer in struct pm_qos_request for that instead of going through pm_qos_array[] to access it. Also update kerneldoc comments that mention pm_qos_class to refer to PM_QOS_CPU_DMA_LATENCY directly instead. Finally, drop register_pm_qos_misc(), introduce cpu_latency_qos_miscdev (with the name field set to "cpu_dma_latency") to implement the CPU latency QoS interface in /dev/ and register it directly from pm_qos_power_init(). After these changes the notion of PM QoS classes remains only in the API (in the form of redundant function parameters that are ignored) and in the definitions of PM QoS trace events. While at it, some redundant local variables are dropped etc. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 20 +++---- kernel/power/qos.c | 121 ++++++++++++++--------------------------- 2 files changed, 51 insertions(+), 90 deletions(-) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 48bfb96a9360..bef110aa80cc 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -39,16 +39,6 @@ enum pm_qos_flags_status { #define PM_QOS_FLAG_NO_POWER_OFF (1 << 0) -struct pm_qos_request { - struct plist_node node; - int pm_qos_class; -}; - -struct pm_qos_flags_request { - struct list_head node; - s32 flags; /* Do not change to 64 bit */ -}; - enum pm_qos_type { PM_QOS_UNITIALIZED, PM_QOS_MAX, /* return the largest value */ @@ -69,6 +59,16 @@ struct pm_qos_constraints { struct blocking_notifier_head *notifiers; }; +struct pm_qos_request { + struct plist_node node; + struct pm_qos_constraints *qos; +}; + +struct pm_qos_flags_request { + struct list_head node; + s32 flags; /* Do not change to 64 bit */ +}; + struct pm_qos_flags { struct list_head list; s32 effective_flags; /* Do not change to 64 bit */ diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 9f67584d4466..952c5f55e23c 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -54,16 +54,8 @@ * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock * held, taken with _irqsave. One lock to rule them all */ -struct pm_qos_object { - struct pm_qos_constraints *constraints; - struct miscdevice pm_qos_power_miscdev; - char *name; -}; - static DEFINE_SPINLOCK(pm_qos_lock); -static struct pm_qos_object null_pm_qos; - static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); static struct pm_qos_constraints cpu_dma_constraints = { .list = PLIST_HEAD_INIT(cpu_dma_constraints.list), @@ -73,15 +65,6 @@ static struct pm_qos_constraints cpu_dma_constraints = { .type = PM_QOS_MIN, .notifiers = &cpu_dma_lat_notifier, }; -static struct pm_qos_object cpu_dma_pm_qos = { - .constraints = &cpu_dma_constraints, - .name = "cpu_dma_latency", -}; - -static struct pm_qos_object *pm_qos_array[] = { - &null_pm_qos, - &cpu_dma_pm_qos, -}; /** * pm_qos_read_value - Return the current effective constraint value. @@ -248,46 +231,34 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, /** * pm_qos_request - returns current system wide qos expectation - * @pm_qos_class: identification of which qos value is requested + * @pm_qos_class: Ignored. * * This function returns the current target value. */ int pm_qos_request(int pm_qos_class) { - return pm_qos_read_value(pm_qos_array[pm_qos_class]->constraints); + return pm_qos_read_value(&cpu_dma_constraints); } EXPORT_SYMBOL_GPL(pm_qos_request); int pm_qos_request_active(struct pm_qos_request *req) { - return req->pm_qos_class != 0; + return req->qos == &cpu_dma_constraints; } EXPORT_SYMBOL_GPL(pm_qos_request_active); -static void __pm_qos_update_request(struct pm_qos_request *req, - s32 new_value) -{ - trace_pm_qos_update_request(req->pm_qos_class, new_value); - - if (new_value != req->node.prio) - pm_qos_update_target( - pm_qos_array[req->pm_qos_class]->constraints, - &req->node, PM_QOS_UPDATE_REQ, new_value); -} - /** * pm_qos_add_request - inserts new qos request into the list * @req: pointer to a preallocated handle - * @pm_qos_class: identifies which list of qos request to use + * @pm_qos_class: Ignored. * @value: defines the qos request * - * This function inserts a new entry in the pm_qos_class list of requested qos - * performance characteristics. It recomputes the aggregate QoS expectations - * for the pm_qos_class of parameters and initializes the pm_qos_request + * This function inserts a new entry in the PM_QOS_CPU_DMA_LATENCY list of + * requested QoS performance characteristics. It recomputes the aggregate QoS + * expectations for the PM_QOS_CPU_DMA_LATENCY list and initializes the @req * handle. Caller needs to save this handle for later use in updates and * removal. */ - void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value) { @@ -298,10 +269,11 @@ void pm_qos_add_request(struct pm_qos_request *req, WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); return; } - req->pm_qos_class = pm_qos_class; - trace_pm_qos_add_request(pm_qos_class, value); - pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints, - &req->node, PM_QOS_ADD_REQ, value); + + trace_pm_qos_add_request(PM_QOS_CPU_DMA_LATENCY, value); + + req->qos = &cpu_dma_constraints; + pm_qos_update_target(req->qos, &req->node, PM_QOS_ADD_REQ, value); } EXPORT_SYMBOL_GPL(pm_qos_add_request); @@ -310,13 +282,12 @@ EXPORT_SYMBOL_GPL(pm_qos_add_request); * @req : handle to list element holding a pm_qos request to use * @value: defines the qos request * - * Updates an existing qos request for the pm_qos_class of parameters along - * with updating the target pm_qos_class value. + * Updates an existing qos request for the PM_QOS_CPU_DMA_LATENCY list along + * with updating the target PM_QOS_CPU_DMA_LATENCY value. * * Attempts are made to make this code callable on hot code paths. */ -void pm_qos_update_request(struct pm_qos_request *req, - s32 new_value) +void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) { if (!req) /*guard against callers passing in null */ return; @@ -326,7 +297,12 @@ void pm_qos_update_request(struct pm_qos_request *req, return; } - __pm_qos_update_request(req, new_value); + trace_pm_qos_update_request(PM_QOS_CPU_DMA_LATENCY, new_value); + + if (new_value == req->node.prio) + return; + + pm_qos_update_target(req->qos, &req->node, PM_QOS_UPDATE_REQ, new_value); } EXPORT_SYMBOL_GPL(pm_qos_update_request); @@ -335,7 +311,7 @@ EXPORT_SYMBOL_GPL(pm_qos_update_request); * @req: handle to request list element * * Will remove pm qos request from the list of constraints and - * recompute the current target value for the pm_qos_class. Call this + * recompute the current target value for PM_QOS_CPU_DMA_LATENCY. Call this * on slow code paths. */ void pm_qos_remove_request(struct pm_qos_request *req) @@ -349,9 +325,9 @@ void pm_qos_remove_request(struct pm_qos_request *req) return; } - trace_pm_qos_remove_request(req->pm_qos_class, PM_QOS_DEFAULT_VALUE); - pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints, - &req->node, PM_QOS_REMOVE_REQ, + trace_pm_qos_remove_request(PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); + + pm_qos_update_target(req->qos, &req->node, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } @@ -359,41 +335,31 @@ EXPORT_SYMBOL_GPL(pm_qos_remove_request); /** * pm_qos_add_notifier - sets notification entry for changes to target value - * @pm_qos_class: identifies which qos target changes should be notified. + * @pm_qos_class: Ignored. * @notifier: notifier block managed by caller. * * will register the notifier into a notification chain that gets called - * upon changes to the pm_qos_class target value. + * upon changes to the PM_QOS_CPU_DMA_LATENCY target value. */ int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) { - int retval; - - retval = blocking_notifier_chain_register( - pm_qos_array[pm_qos_class]->constraints->notifiers, - notifier); - - return retval; + return blocking_notifier_chain_register(cpu_dma_constraints.notifiers, + notifier); } EXPORT_SYMBOL_GPL(pm_qos_add_notifier); /** * pm_qos_remove_notifier - deletes notification entry from chain. - * @pm_qos_class: identifies which qos target changes are notified. + * @pm_qos_class: Ignored. * @notifier: notifier block to be removed. * * will remove the notifier from the notification chain that gets called - * upon changes to the pm_qos_class target value. + * upon changes to the PM_QOS_CPU_DMA_LATENCY target value. */ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) { - int retval; - - retval = blocking_notifier_chain_unregister( - pm_qos_array[pm_qos_class]->constraints->notifiers, - notifier); - - return retval; + return blocking_notifier_chain_unregister(cpu_dma_constraints.notifiers, + notifier); } EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); @@ -436,7 +402,7 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, return -EINVAL; spin_lock_irqsave(&pm_qos_lock, flags); - value = pm_qos_get_value(pm_qos_array[req->pm_qos_class]->constraints); + value = pm_qos_get_value(&cpu_dma_constraints); spin_unlock_irqrestore(&pm_qos_lock, flags); return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); @@ -471,25 +437,20 @@ static const struct file_operations pm_qos_power_fops = { .llseek = noop_llseek, }; -static int register_pm_qos_misc(struct pm_qos_object *qos) -{ - qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; - qos->pm_qos_power_miscdev.name = qos->name; - qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; - - return misc_register(&qos->pm_qos_power_miscdev); -} +static struct miscdevice cpu_latency_qos_miscdev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "cpu_dma_latency", + .fops = &pm_qos_power_fops, +}; static int __init pm_qos_power_init(void) { int ret; - BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES); - - ret = register_pm_qos_misc(pm_qos_array[PM_QOS_CPU_DMA_LATENCY]); + ret = misc_register(&cpu_latency_qos_miscdev); if (ret < 0) pr_err("%s: %s setup failed\n", __func__, - pm_qos_array[PM_QOS_CPU_DMA_LATENCY]->name); + cpu_latency_qos_miscdev.name); return ret; } From 3a4a0042228a854d9b1073050620820b4a977e6e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:02:30 +0100 Subject: [PATCH 09/30] PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY notifier chain Notice that pm_qos_remove_notifier() is not used at all and the only caller of pm_qos_add_notifier() is the cpuidle core, which only needs the PM_QOS_CPU_DMA_LATENCY notifier to invoke wake_up_all_idle_cpus() upon changes of the PM_QOS_CPU_DMA_LATENCY target value. First, to ensure that wake_up_all_idle_cpus() will be called whenever the PM_QOS_CPU_DMA_LATENCY target value changes, modify the pm_qos_add/update/remove_request() family of functions to check if the effective constraint for the PM_QOS_CPU_DMA_LATENCY has changed and call wake_up_all_idle_cpus() directly in that case. Next, drop the PM_QOS_CPU_DMA_LATENCY notifier from cpuidle as it is not necessary any more. Finally, drop both pm_qos_add_notifier() and pm_qos_remove_notifier(), as they have no callers now, along with cpu_dma_lat_notifier which is only used by them. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/cpuidle/cpuidle.c | 40 +-------------------------------- include/linux/pm_qos.h | 2 -- kernel/power/qos.c | 47 +++++++++------------------------------ 3 files changed, 12 insertions(+), 77 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index de81298051b3..c149d9e20dfd 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -736,53 +736,15 @@ int cpuidle_register(struct cpuidle_driver *drv, } EXPORT_SYMBOL_GPL(cpuidle_register); -#ifdef CONFIG_SMP - -/* - * This function gets called when a part of the kernel has a new latency - * requirement. This means we need to get all processors out of their C-state, - * and then recalculate a new suitable C-state. Just do a cross-cpu IPI; that - * wakes them all right up. - */ -static int cpuidle_latency_notify(struct notifier_block *b, - unsigned long l, void *v) -{ - wake_up_all_idle_cpus(); - return NOTIFY_OK; -} - -static struct notifier_block cpuidle_latency_notifier = { - .notifier_call = cpuidle_latency_notify, -}; - -static inline void latency_notifier_init(struct notifier_block *n) -{ - pm_qos_add_notifier(PM_QOS_CPU_DMA_LATENCY, n); -} - -#else /* CONFIG_SMP */ - -#define latency_notifier_init(x) do { } while (0) - -#endif /* CONFIG_SMP */ - /** * cpuidle_init - core initializer */ static int __init cpuidle_init(void) { - int ret; - if (cpuidle_disabled()) return -ENODEV; - ret = cpuidle_add_interface(cpu_subsys.dev_root); - if (ret) - return ret; - - latency_notifier_init(&cpuidle_latency_notifier); - - return 0; + return cpuidle_add_interface(cpu_subsys.dev_root); } module_param(off, int, 0444); diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index bef110aa80cc..cb57e5918a25 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -149,8 +149,6 @@ void pm_qos_update_request(struct pm_qos_request *req, void pm_qos_remove_request(struct pm_qos_request *req); int pm_qos_request(int pm_qos_class); -int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier); -int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_request_active(struct pm_qos_request *req); s32 pm_qos_read_value(struct pm_qos_constraints *c); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 952c5f55e23c..201b43bc6457 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -56,14 +56,12 @@ */ static DEFINE_SPINLOCK(pm_qos_lock); -static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); static struct pm_qos_constraints cpu_dma_constraints = { .list = PLIST_HEAD_INIT(cpu_dma_constraints.list), .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .no_constraint_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .type = PM_QOS_MIN, - .notifiers = &cpu_dma_lat_notifier, }; /** @@ -247,6 +245,14 @@ int pm_qos_request_active(struct pm_qos_request *req) } EXPORT_SYMBOL_GPL(pm_qos_request_active); +static void cpu_latency_qos_update(struct pm_qos_request *req, + enum pm_qos_req_action action, s32 value) +{ + int ret = pm_qos_update_target(req->qos, &req->node, action, value); + if (ret > 0) + wake_up_all_idle_cpus(); +} + /** * pm_qos_add_request - inserts new qos request into the list * @req: pointer to a preallocated handle @@ -273,7 +279,7 @@ void pm_qos_add_request(struct pm_qos_request *req, trace_pm_qos_add_request(PM_QOS_CPU_DMA_LATENCY, value); req->qos = &cpu_dma_constraints; - pm_qos_update_target(req->qos, &req->node, PM_QOS_ADD_REQ, value); + cpu_latency_qos_update(req, PM_QOS_ADD_REQ, value); } EXPORT_SYMBOL_GPL(pm_qos_add_request); @@ -302,7 +308,7 @@ void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) if (new_value == req->node.prio) return; - pm_qos_update_target(req->qos, &req->node, PM_QOS_UPDATE_REQ, new_value); + cpu_latency_qos_update(req, PM_QOS_UPDATE_REQ, new_value); } EXPORT_SYMBOL_GPL(pm_qos_update_request); @@ -327,42 +333,11 @@ void pm_qos_remove_request(struct pm_qos_request *req) trace_pm_qos_remove_request(PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); - pm_qos_update_target(req->qos, &req->node, PM_QOS_REMOVE_REQ, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } EXPORT_SYMBOL_GPL(pm_qos_remove_request); -/** - * pm_qos_add_notifier - sets notification entry for changes to target value - * @pm_qos_class: Ignored. - * @notifier: notifier block managed by caller. - * - * will register the notifier into a notification chain that gets called - * upon changes to the PM_QOS_CPU_DMA_LATENCY target value. - */ -int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) -{ - return blocking_notifier_chain_register(cpu_dma_constraints.notifiers, - notifier); -} -EXPORT_SYMBOL_GPL(pm_qos_add_notifier); - -/** - * pm_qos_remove_notifier - deletes notification entry from chain. - * @pm_qos_class: Ignored. - * @notifier: notifier block to be removed. - * - * will remove the notifier from the notification chain that gets called - * upon changes to the PM_QOS_CPU_DMA_LATENCY target value. - */ -int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) -{ - return blocking_notifier_chain_unregister(cpu_dma_constraints.notifiers, - notifier); -} -EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); - /* User space interface to global PM QoS via misc device. */ static int pm_qos_power_open(struct inode *inode, struct file *filp) From 2552d3520132a22834e0be85c51168a7a798608c Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:04:31 +0100 Subject: [PATCH 10/30] PM: QoS: Rename things related to the CPU latency QoS First, rename PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE to PM_QOS_CPU_LATENCY_DEFAULT_VALUE and update all of the code referring to it accordingly. Next, rename cpu_dma_constraints to cpu_latency_constraints, move the definition of it closer to the functions referring to it and update all of them accordingly. [While at it, add a comment to mark the start of the code related to the CPU latency QoS.] Finally, rename the pm_qos_power_*() family of functions and pm_qos_power_fops to cpu_latency_qos_*() and cpu_latency_qos_fops, respectively, and update the definition of cpu_latency_qos_miscdev. [While at it, update the miscdev interface code start comment.] No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Acked-by: Greg Kroah-Hartman Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/tty/serial/8250/8250_omap.c | 6 ++-- drivers/tty/serial/omap-serial.c | 6 ++-- include/linux/pm_qos.h | 2 +- kernel/power/qos.c | 56 +++++++++++++++-------------- 4 files changed, 36 insertions(+), 34 deletions(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 6f343ca08440..19f8d2f9e7ba 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1222,8 +1222,8 @@ static int omap8250_probe(struct platform_device *pdev) DEFAULT_CLK_SPEED); } - priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; - priv->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; + priv->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; + priv->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; pm_qos_add_request(&priv->pm_qos_request, PM_QOS_CPU_DMA_LATENCY, priv->latency); INIT_WORK(&priv->qos_work, omap8250_uart_qos_work); @@ -1445,7 +1445,7 @@ static int omap8250_runtime_suspend(struct device *dev) if (up->dma && up->dma->rxchan) omap_8250_rx_dma_flush(up); - priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; + priv->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; schedule_work(&priv->qos_work); return 0; diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index 48017cec7f2f..ce2558767eee 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1722,8 +1722,8 @@ static int serial_omap_probe(struct platform_device *pdev) DEFAULT_CLK_SPEED); } - up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; - up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; + up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; + up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; pm_qos_add_request(&up->pm_qos_request, PM_QOS_CPU_DMA_LATENCY, up->latency); INIT_WORK(&up->qos_work, serial_omap_uart_qos_work); @@ -1869,7 +1869,7 @@ static int serial_omap_runtime_suspend(struct device *dev) serial_omap_enable_wakeup(up, true); - up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; + up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; schedule_work(&up->qos_work); return 0; diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index cb57e5918a25..a3e0bfc6c470 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -28,7 +28,7 @@ enum pm_qos_flags_status { #define PM_QOS_LATENCY_ANY S32_MAX #define PM_QOS_LATENCY_ANY_NS ((s64)PM_QOS_LATENCY_ANY * NSEC_PER_USEC) -#define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC) +#define PM_QOS_CPU_LATENCY_DEFAULT_VALUE (2000 * USEC_PER_SEC) #define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE PM_QOS_LATENCY_ANY #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT PM_QOS_LATENCY_ANY #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS PM_QOS_LATENCY_ANY_NS diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 201b43bc6457..a6bf53e9db17 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -56,14 +56,6 @@ */ static DEFINE_SPINLOCK(pm_qos_lock); -static struct pm_qos_constraints cpu_dma_constraints = { - .list = PLIST_HEAD_INIT(cpu_dma_constraints.list), - .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, - .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, - .no_constraint_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, - .type = PM_QOS_MIN, -}; - /** * pm_qos_read_value - Return the current effective constraint value. * @c: List of PM QoS constraint requests. @@ -227,6 +219,16 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, return prev_value != curr_value; } +/* Definitions related to the CPU latency QoS. */ + +static struct pm_qos_constraints cpu_latency_constraints = { + .list = PLIST_HEAD_INIT(cpu_latency_constraints.list), + .target_value = PM_QOS_CPU_LATENCY_DEFAULT_VALUE, + .default_value = PM_QOS_CPU_LATENCY_DEFAULT_VALUE, + .no_constraint_value = PM_QOS_CPU_LATENCY_DEFAULT_VALUE, + .type = PM_QOS_MIN, +}; + /** * pm_qos_request - returns current system wide qos expectation * @pm_qos_class: Ignored. @@ -235,13 +237,13 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, */ int pm_qos_request(int pm_qos_class) { - return pm_qos_read_value(&cpu_dma_constraints); + return pm_qos_read_value(&cpu_latency_constraints); } EXPORT_SYMBOL_GPL(pm_qos_request); int pm_qos_request_active(struct pm_qos_request *req) { - return req->qos == &cpu_dma_constraints; + return req->qos == &cpu_latency_constraints; } EXPORT_SYMBOL_GPL(pm_qos_request_active); @@ -278,7 +280,7 @@ void pm_qos_add_request(struct pm_qos_request *req, trace_pm_qos_add_request(PM_QOS_CPU_DMA_LATENCY, value); - req->qos = &cpu_dma_constraints; + req->qos = &cpu_latency_constraints; cpu_latency_qos_update(req, PM_QOS_ADD_REQ, value); } EXPORT_SYMBOL_GPL(pm_qos_add_request); @@ -338,9 +340,9 @@ void pm_qos_remove_request(struct pm_qos_request *req) } EXPORT_SYMBOL_GPL(pm_qos_remove_request); -/* User space interface to global PM QoS via misc device. */ +/* User space interface to the CPU latency QoS via misc device. */ -static int pm_qos_power_open(struct inode *inode, struct file *filp) +static int cpu_latency_qos_open(struct inode *inode, struct file *filp) { struct pm_qos_request *req; @@ -354,7 +356,7 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp) return 0; } -static int pm_qos_power_release(struct inode *inode, struct file *filp) +static int cpu_latency_qos_release(struct inode *inode, struct file *filp) { struct pm_qos_request *req = filp->private_data; @@ -366,8 +368,8 @@ static int pm_qos_power_release(struct inode *inode, struct file *filp) return 0; } -static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, - size_t count, loff_t *f_pos) +static ssize_t cpu_latency_qos_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos) { struct pm_qos_request *req = filp->private_data; unsigned long flags; @@ -377,14 +379,14 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, return -EINVAL; spin_lock_irqsave(&pm_qos_lock, flags); - value = pm_qos_get_value(&cpu_dma_constraints); + value = pm_qos_get_value(&cpu_latency_constraints); spin_unlock_irqrestore(&pm_qos_lock, flags); return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); } -static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, - size_t count, loff_t *f_pos) +static ssize_t cpu_latency_qos_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) { s32 value; @@ -404,21 +406,21 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, return count; } -static const struct file_operations pm_qos_power_fops = { - .write = pm_qos_power_write, - .read = pm_qos_power_read, - .open = pm_qos_power_open, - .release = pm_qos_power_release, +static const struct file_operations cpu_latency_qos_fops = { + .write = cpu_latency_qos_write, + .read = cpu_latency_qos_read, + .open = cpu_latency_qos_open, + .release = cpu_latency_qos_release, .llseek = noop_llseek, }; static struct miscdevice cpu_latency_qos_miscdev = { .minor = MISC_DYNAMIC_MINOR, .name = "cpu_dma_latency", - .fops = &pm_qos_power_fops, + .fops = &cpu_latency_qos_fops, }; -static int __init pm_qos_power_init(void) +static int __init cpu_latency_qos_init(void) { int ret; @@ -429,7 +431,7 @@ static int __init pm_qos_power_init(void) return ret; } -late_initcall(pm_qos_power_init); +late_initcall(cpu_latency_qos_init); /* Definitions related to the frequency QoS below. */ From 333eed7d20069e2d80446f5fdf9ac3868b55e7b9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:06:17 +0100 Subject: [PATCH 11/30] PM: QoS: Simplify definitions of CPU latency QoS trace events Modify the definitions of the CPU latency QoS trace events to take one argument (since PM_QOS_CPU_DMA_LATENCY is always passed as the pm_qos_class argument to them) and update the documentation of them accordingly (while at it, make it explicitly mention CPU latency QoS and relocate it after the device PM QoS trace events documentation). The names and output format of the trace events do not change to preserve user space compatibility. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- Documentation/trace/events-power.rst | 19 ++++++++------- include/trace/events/power.h | 35 ++++++++++++++-------------- kernel/power/qos.c | 16 ++++++------- 3 files changed, 35 insertions(+), 35 deletions(-) diff --git a/Documentation/trace/events-power.rst b/Documentation/trace/events-power.rst index eec7453a168e..f45bf11fa88d 100644 --- a/Documentation/trace/events-power.rst +++ b/Documentation/trace/events-power.rst @@ -73,14 +73,6 @@ The second parameter is the power domain target state. ================ The PM QoS events are used for QoS add/update/remove request and for target/flags update. -:: - - pm_qos_add_request "pm_qos_class=%s value=%d" - pm_qos_update_request "pm_qos_class=%s value=%d" - pm_qos_remove_request "pm_qos_class=%s value=%d" - -The first parameter gives the QoS class name (e.g. "CPU_DMA_LATENCY"). -The second parameter is value to be added/updated/removed. :: pm_qos_update_target "action=%s prev_value=%d curr_value=%d" @@ -90,7 +82,7 @@ The first parameter gives the QoS action name (e.g. "ADD_REQ"). The second parameter is the previous QoS value. The third parameter is the current QoS value to update. -And, there are also events used for device PM QoS add/update/remove request. +There are also events used for device PM QoS add/update/remove request. :: dev_pm_qos_add_request "device=%s type=%s new_value=%d" @@ -101,3 +93,12 @@ The first parameter gives the device name which tries to add/update/remove QoS requests. The second parameter gives the request type (e.g. "DEV_PM_QOS_RESUME_LATENCY"). The third parameter is value to be added/updated/removed. + +And, there are events used for CPU latency QoS add/update/remove request. +:: + + pm_qos_add_request "value=%d" + pm_qos_update_request "value=%d" + pm_qos_remove_request "value=%d" + +The parameter is the value to be added/updated/removed. diff --git a/include/trace/events/power.h b/include/trace/events/power.h index ecf39daabf16..af5018aa9517 100644 --- a/include/trace/events/power.h +++ b/include/trace/events/power.h @@ -359,51 +359,50 @@ DEFINE_EVENT(power_domain, power_domain_target, ); /* - * The pm qos events are used for pm qos update + * CPU latency QoS events used for global CPU latency QoS list updates */ -DECLARE_EVENT_CLASS(pm_qos_request, +DECLARE_EVENT_CLASS(cpu_latency_qos_request, - TP_PROTO(int pm_qos_class, s32 value), + TP_PROTO(s32 value), - TP_ARGS(pm_qos_class, value), + TP_ARGS(value), TP_STRUCT__entry( - __field( int, pm_qos_class ) __field( s32, value ) ), TP_fast_assign( - __entry->pm_qos_class = pm_qos_class; __entry->value = value; ), - TP_printk("pm_qos_class=%s value=%d", - __print_symbolic(__entry->pm_qos_class, - { PM_QOS_CPU_DMA_LATENCY, "CPU_DMA_LATENCY" }), + TP_printk("CPU_DMA_LATENCY value=%d", __entry->value) ); -DEFINE_EVENT(pm_qos_request, pm_qos_add_request, +DEFINE_EVENT(cpu_latency_qos_request, pm_qos_add_request, - TP_PROTO(int pm_qos_class, s32 value), + TP_PROTO(s32 value), - TP_ARGS(pm_qos_class, value) + TP_ARGS(value) ); -DEFINE_EVENT(pm_qos_request, pm_qos_update_request, +DEFINE_EVENT(cpu_latency_qos_request, pm_qos_update_request, - TP_PROTO(int pm_qos_class, s32 value), + TP_PROTO(s32 value), - TP_ARGS(pm_qos_class, value) + TP_ARGS(value) ); -DEFINE_EVENT(pm_qos_request, pm_qos_remove_request, +DEFINE_EVENT(cpu_latency_qos_request, pm_qos_remove_request, - TP_PROTO(int pm_qos_class, s32 value), + TP_PROTO(s32 value), - TP_ARGS(pm_qos_class, value) + TP_ARGS(value) ); +/* + * General PM QoS events used for updates of PM QoS request lists + */ DECLARE_EVENT_CLASS(pm_qos_update, TP_PROTO(enum pm_qos_req_action action, int prev_value, int curr_value), diff --git a/kernel/power/qos.c b/kernel/power/qos.c index a6bf53e9db17..afac7010e0f2 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -247,8 +247,8 @@ int pm_qos_request_active(struct pm_qos_request *req) } EXPORT_SYMBOL_GPL(pm_qos_request_active); -static void cpu_latency_qos_update(struct pm_qos_request *req, - enum pm_qos_req_action action, s32 value) +static void cpu_latency_qos_apply(struct pm_qos_request *req, + enum pm_qos_req_action action, s32 value) { int ret = pm_qos_update_target(req->qos, &req->node, action, value); if (ret > 0) @@ -278,10 +278,10 @@ void pm_qos_add_request(struct pm_qos_request *req, return; } - trace_pm_qos_add_request(PM_QOS_CPU_DMA_LATENCY, value); + trace_pm_qos_add_request(value); req->qos = &cpu_latency_constraints; - cpu_latency_qos_update(req, PM_QOS_ADD_REQ, value); + cpu_latency_qos_apply(req, PM_QOS_ADD_REQ, value); } EXPORT_SYMBOL_GPL(pm_qos_add_request); @@ -305,12 +305,12 @@ void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) return; } - trace_pm_qos_update_request(PM_QOS_CPU_DMA_LATENCY, new_value); + trace_pm_qos_update_request(new_value); if (new_value == req->node.prio) return; - cpu_latency_qos_update(req, PM_QOS_UPDATE_REQ, new_value); + cpu_latency_qos_apply(req, PM_QOS_UPDATE_REQ, new_value); } EXPORT_SYMBOL_GPL(pm_qos_update_request); @@ -333,9 +333,9 @@ void pm_qos_remove_request(struct pm_qos_request *req) return; } - trace_pm_qos_remove_request(PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); + trace_pm_qos_remove_request(PM_QOS_DEFAULT_VALUE); - cpu_latency_qos_update(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } EXPORT_SYMBOL_GPL(pm_qos_remove_request); From e033b6c175a32870a2f7cd3741c0d48c858c2d04 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:07:01 +0100 Subject: [PATCH 12/30] PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h Change the return type of pm_qos_request() to be the same as the one of pm_qos_read_value() called by it internally and stop exporting it to modules (because its only caller, cpuidle, is not modular). Also move the pm_qos_read_value() header away from the CPU latency QoS API function headers in pm_qos.h (because it technically does not belong to that API). No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 6 +++--- kernel/power/qos.c | 3 +-- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index a3e0bfc6c470..3c4bee29ecda 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -137,20 +137,20 @@ static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req) return req->dev != NULL; } +s32 pm_qos_read_value(struct pm_qos_constraints *c); int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, enum pm_qos_req_action action, int value); bool pm_qos_update_flags(struct pm_qos_flags *pqf, struct pm_qos_flags_request *req, enum pm_qos_req_action action, s32 val); + void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value); void pm_qos_update_request(struct pm_qos_request *req, s32 new_value); void pm_qos_remove_request(struct pm_qos_request *req); - -int pm_qos_request(int pm_qos_class); +s32 pm_qos_request(int pm_qos_class); int pm_qos_request_active(struct pm_qos_request *req); -s32 pm_qos_read_value(struct pm_qos_constraints *c); #ifdef CONFIG_PM enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index afac7010e0f2..7bb55aca03bb 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -235,11 +235,10 @@ static struct pm_qos_constraints cpu_latency_constraints = { * * This function returns the current target value. */ -int pm_qos_request(int pm_qos_class) +s32 pm_qos_request(int pm_qos_class) { return pm_qos_read_value(&cpu_latency_constraints); } -EXPORT_SYMBOL_GPL(pm_qos_request); int pm_qos_request_active(struct pm_qos_request *req) { From fa048c59bf1ba13d8fe61890495577073a0ea919 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:07:42 +0100 Subject: [PATCH 13/30] PM: QoS: Add CPU latency QoS API wrappers Introduce (temporary) wrappers around pm_qos_request(), pm_qos_request_active() and pm_qos_add/update/remove_request() to provide replacements for them with function signatures that will be used in the final CPU latency QoS API, so that the users of it can be switched over to the new arrangement one by one before the API is finally set. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 3c4bee29ecda..63d39e66f95d 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -152,6 +152,33 @@ void pm_qos_remove_request(struct pm_qos_request *req); s32 pm_qos_request(int pm_qos_class); int pm_qos_request_active(struct pm_qos_request *req); +static inline void cpu_latency_qos_add_request(struct pm_qos_request *req, + s32 value) +{ + pm_qos_add_request(req, PM_QOS_CPU_DMA_LATENCY, value); +} + +static inline void cpu_latency_qos_update_request(struct pm_qos_request *req, + s32 new_value) +{ + pm_qos_update_request(req, new_value); +} + +static inline void cpu_latency_qos_remove_request(struct pm_qos_request *req) +{ + pm_qos_remove_request(req); +} + +static inline bool cpu_latency_qos_request_active(struct pm_qos_request *req) +{ + return pm_qos_request_active(req); +} + +static inline s32 cpu_latency_qos_limit(void) +{ + return pm_qos_request(PM_QOS_CPU_DMA_LATENCY); +} + #ifdef CONFIG_PM enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask); enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask); From f60ccc3558dd83c4db68736625642d54bf38a6db Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:08:42 +0100 Subject: [PATCH 14/30] cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request() Call cpu_latency_qos_limit() instead of pm_qos_request(), because the latter is going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/cpuidle/governor.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c index e48271e117a3..29acaf48e575 100644 --- a/drivers/cpuidle/governor.c +++ b/drivers/cpuidle/governor.c @@ -109,9 +109,9 @@ int cpuidle_register_governor(struct cpuidle_governor *gov) */ s64 cpuidle_governor_latency_req(unsigned int cpu) { - int global_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); struct device *device = get_cpu_device(cpu); int device_req = dev_pm_qos_raw_resume_latency(device); + int global_req = cpu_latency_qos_limit(); if (device_req > global_req) device_req = global_req; From fe66a17ecd4912401afd61517eadae2e9e4ce0ae Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:10:00 +0100 Subject: [PATCH 15/30] x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/update/remove_request() instead of pm_qos_add/update/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Andy Shevchenko Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- arch/x86/platform/intel/iosf_mbi.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/x86/platform/intel/iosf_mbi.c b/arch/x86/platform/intel/iosf_mbi.c index 9e2444500428..526f70f27c1c 100644 --- a/arch/x86/platform/intel/iosf_mbi.c +++ b/arch/x86/platform/intel/iosf_mbi.c @@ -265,7 +265,7 @@ static void iosf_mbi_reset_semaphore(void) iosf_mbi_sem_address, 0, PUNIT_SEMAPHORE_BIT)) dev_err(&mbi_pdev->dev, "Error P-Unit semaphore reset failed\n"); - pm_qos_update_request(&iosf_mbi_pm_qos, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(&iosf_mbi_pm_qos, PM_QOS_DEFAULT_VALUE); blocking_notifier_call_chain(&iosf_mbi_pmic_bus_access_notifier, MBI_PMIC_BUS_ACCESS_END, NULL); @@ -301,8 +301,8 @@ static void iosf_mbi_reset_semaphore(void) * 4) When CPU cores enter C6 or C7 the P-Unit needs to talk to the PMIC * if this happens while the kernel itself is accessing the PMIC I2C bus * the SoC hangs. - * As the third step we call pm_qos_update_request() to disallow the CPU - * to enter C6 or C7. + * As the third step we call cpu_latency_qos_update_request() to disallow the + * CPU to enter C6 or C7. * * 5) The P-Unit has a PMIC bus semaphore which we can request to stop * autonomous P-Unit tasks from accessing the PMIC I2C bus while we hold it. @@ -338,7 +338,7 @@ int iosf_mbi_block_punit_i2c_access(void) * requires the P-Unit to talk to the PMIC and if this happens while * we're holding the semaphore, the SoC hangs. */ - pm_qos_update_request(&iosf_mbi_pm_qos, 0); + cpu_latency_qos_update_request(&iosf_mbi_pm_qos, 0); /* host driver writes to side band semaphore register */ ret = iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, @@ -547,8 +547,7 @@ static int __init iosf_mbi_init(void) { iosf_debugfs_init(); - pm_qos_add_request(&iosf_mbi_pm_qos, PM_QOS_CPU_DMA_LATENCY, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(&iosf_mbi_pm_qos, PM_QOS_DEFAULT_VALUE); return pci_register_driver(&iosf_mbi_pci_driver); } @@ -561,7 +560,7 @@ static void __exit iosf_mbi_exit(void) pci_dev_put(mbi_pdev); mbi_pdev = NULL; - pm_qos_remove_request(&iosf_mbi_pm_qos); + cpu_latency_qos_remove_request(&iosf_mbi_pm_qos); } module_init(iosf_mbi_init); From 4d4dda487a364e601a926443adf731b6fe64ae21 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:12:10 +0100 Subject: [PATCH 16/30] drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/update/remove_request() instead of pm_qos_add/update/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria Acked-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_dp.c | 4 ++-- drivers/gpu/drm/i915/i915_drv.c | 12 +++++------- drivers/gpu/drm/i915/intel_sideband.c | 5 +++-- 3 files changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index c7424e2a04a3..208457005a11 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -1360,7 +1360,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp, * lowest possible wakeup latency and so prevent the cpu from going into * deep sleep states. */ - pm_qos_update_request(&i915->pm_qos, 0); + cpu_latency_qos_update_request(&i915->pm_qos, 0); intel_dp_check_edp(intel_dp); @@ -1488,7 +1488,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp, ret = recv_bytes; out: - pm_qos_update_request(&i915->pm_qos, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(&i915->pm_qos, PM_QOS_DEFAULT_VALUE); if (vdd) edp_panel_vdd_off(intel_dp, false); diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index f7385abdd74b..74481a189cfc 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -502,8 +502,7 @@ static int i915_driver_early_probe(struct drm_i915_private *dev_priv) mutex_init(&dev_priv->backlight_lock); mutex_init(&dev_priv->sb_lock); - pm_qos_add_request(&dev_priv->sb_qos, - PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(&dev_priv->sb_qos, PM_QOS_DEFAULT_VALUE); mutex_init(&dev_priv->av_mutex); mutex_init(&dev_priv->wm.wm_mutex); @@ -568,7 +567,7 @@ static void i915_driver_late_release(struct drm_i915_private *dev_priv) vlv_free_s0ix_state(dev_priv); i915_workqueues_cleanup(dev_priv); - pm_qos_remove_request(&dev_priv->sb_qos); + cpu_latency_qos_remove_request(&dev_priv->sb_qos); mutex_destroy(&dev_priv->sb_lock); } @@ -1226,8 +1225,7 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv) } } - pm_qos_add_request(&dev_priv->pm_qos, PM_QOS_CPU_DMA_LATENCY, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(&dev_priv->pm_qos, PM_QOS_DEFAULT_VALUE); intel_gt_init_workarounds(dev_priv); @@ -1273,7 +1271,7 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv) err_msi: if (pdev->msi_enabled) pci_disable_msi(pdev); - pm_qos_remove_request(&dev_priv->pm_qos); + cpu_latency_qos_remove_request(&dev_priv->pm_qos); err_mem_regions: intel_memory_regions_driver_release(dev_priv); err_ggtt: @@ -1296,7 +1294,7 @@ static void i915_driver_hw_remove(struct drm_i915_private *dev_priv) if (pdev->msi_enabled) pci_disable_msi(pdev); - pm_qos_remove_request(&dev_priv->pm_qos); + cpu_latency_qos_remove_request(&dev_priv->pm_qos); } /** diff --git a/drivers/gpu/drm/i915/intel_sideband.c b/drivers/gpu/drm/i915/intel_sideband.c index cbfb7171d62d..0648eda309e4 100644 --- a/drivers/gpu/drm/i915/intel_sideband.c +++ b/drivers/gpu/drm/i915/intel_sideband.c @@ -60,7 +60,7 @@ static void __vlv_punit_get(struct drm_i915_private *i915) * to the Valleyview P-unit and not all sideband communications. */ if (IS_VALLEYVIEW(i915)) { - pm_qos_update_request(&i915->sb_qos, 0); + cpu_latency_qos_update_request(&i915->sb_qos, 0); on_each_cpu(ping, NULL, 1); } } @@ -68,7 +68,8 @@ static void __vlv_punit_get(struct drm_i915_private *i915) static void __vlv_punit_put(struct drm_i915_private *i915) { if (IS_VALLEYVIEW(i915)) - pm_qos_update_request(&i915->sb_qos, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(&i915->sb_qos, + PM_QOS_DEFAULT_VALUE); iosf_mbi_punit_release(); } From 6ca50a47c0962cbfda36c82663c5146e9d7bb094 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:13:17 +0100 Subject: [PATCH 17/30] drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/remove_request() and cpu_latency_qos_request_active() instead of pm_qos_add/remove_request() and pm_qos_request_active(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria Acked-by: Sebastian Reichel --- drivers/hsi/clients/cmt_speech.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/hsi/clients/cmt_speech.c b/drivers/hsi/clients/cmt_speech.c index 9eec970cdfa5..89869c66fb9d 100644 --- a/drivers/hsi/clients/cmt_speech.c +++ b/drivers/hsi/clients/cmt_speech.c @@ -965,14 +965,13 @@ static int cs_hsi_buf_config(struct cs_hsi_iface *hi, if (old_state != hi->iface_state) { if (hi->iface_state == CS_STATE_CONFIGURED) { - pm_qos_add_request(&hi->pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, + cpu_latency_qos_add_request(&hi->pm_qos_req, CS_QOS_LATENCY_FOR_DATA_USEC); local_bh_disable(); cs_hsi_read_on_data(hi); local_bh_enable(); } else if (old_state == CS_STATE_CONFIGURED) { - pm_qos_remove_request(&hi->pm_qos_req); + cpu_latency_qos_remove_request(&hi->pm_qos_req); } } return r; @@ -1075,8 +1074,8 @@ static void cs_hsi_stop(struct cs_hsi_iface *hi) WARN_ON(!cs_state_idle(hi->control_state)); WARN_ON(!cs_state_idle(hi->data_state)); - if (pm_qos_request_active(&hi->pm_qos_req)) - pm_qos_remove_request(&hi->pm_qos_req); + if (cpu_latency_qos_request_active(&hi->pm_qos_req)) + cpu_latency_qos_remove_request(&hi->pm_qos_req); spin_lock_bh(&hi->lock); cs_hsi_free_data(hi); From 7c51a06b2560b2ecd6cd01251dc478fce4bd6938 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:17:51 +0100 Subject: [PATCH 18/30] drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/remove_request() instead of pm_qos_add/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Acked-by: Mauro Carvalho Chehab Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/media/pci/saa7134/saa7134-video.c | 5 ++--- drivers/media/platform/via-camera.c | 4 ++-- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/media/pci/saa7134/saa7134-video.c b/drivers/media/pci/saa7134/saa7134-video.c index 342cabf48064..a8ac94fadc14 100644 --- a/drivers/media/pci/saa7134/saa7134-video.c +++ b/drivers/media/pci/saa7134/saa7134-video.c @@ -1008,8 +1008,7 @@ int saa7134_vb2_start_streaming(struct vb2_queue *vq, unsigned int count) */ if ((dmaq == &dev->video_q && !vb2_is_streaming(&dev->vbi_vbq)) || (dmaq == &dev->vbi_q && !vb2_is_streaming(&dev->video_vbq))) - pm_qos_add_request(&dev->qos_request, - PM_QOS_CPU_DMA_LATENCY, 20); + cpu_latency_qos_add_request(&dev->qos_request, 20); dmaq->seq_nr = 0; return 0; @@ -1024,7 +1023,7 @@ void saa7134_vb2_stop_streaming(struct vb2_queue *vq) if ((dmaq == &dev->video_q && !vb2_is_streaming(&dev->vbi_vbq)) || (dmaq == &dev->vbi_q && !vb2_is_streaming(&dev->video_vbq))) - pm_qos_remove_request(&dev->qos_request); + cpu_latency_qos_remove_request(&dev->qos_request); } static const struct vb2_ops vb2_qops = { diff --git a/drivers/media/platform/via-camera.c b/drivers/media/platform/via-camera.c index 78841b9015ce..1cd4f7be88dd 100644 --- a/drivers/media/platform/via-camera.c +++ b/drivers/media/platform/via-camera.c @@ -646,7 +646,7 @@ static int viacam_vb2_start_streaming(struct vb2_queue *vq, unsigned int count) * requirement which will keep the CPU out of the deeper sleep * states. */ - pm_qos_add_request(&cam->qos_request, PM_QOS_CPU_DMA_LATENCY, 50); + cpu_latency_qos_add_request(&cam->qos_request, 50); viacam_start_engine(cam); return 0; out: @@ -662,7 +662,7 @@ static void viacam_vb2_stop_streaming(struct vb2_queue *vq) struct via_camera *cam = vb2_get_drv_priv(vq); struct via_buffer *buf, *tmp; - pm_qos_remove_request(&cam->qos_request); + cpu_latency_qos_remove_request(&cam->qos_request); viacam_stop_engine(cam); list_for_each_entry_safe(buf, tmp, &cam->buffer_queue, queue) { From d1b98305916bc0b3ab3f52f4f08e4942aa7826a0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:21:53 +0100 Subject: [PATCH 19/30] drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/remove_request() instead of pm_qos_add/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/mmc/host/sdhci-esdhc-imx.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 382f25b2fa45..b2bdf5012c55 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -1452,8 +1452,7 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) pdev->id_entry->driver_data; if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_add_request(&imx_data->pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&imx_data->pm_qos_req, 0); imx_data->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); if (IS_ERR(imx_data->clk_ipg)) { @@ -1572,7 +1571,7 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) clk_disable_unprepare(imx_data->clk_per); free_sdhci: if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_remove_request(&imx_data->pm_qos_req); + cpu_latency_qos_remove_request(&imx_data->pm_qos_req); sdhci_pltfm_free(pdev); return err; } @@ -1595,7 +1594,7 @@ static int sdhci_esdhc_imx_remove(struct platform_device *pdev) clk_disable_unprepare(imx_data->clk_ahb); if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_remove_request(&imx_data->pm_qos_req); + cpu_latency_qos_remove_request(&imx_data->pm_qos_req); sdhci_pltfm_free(pdev); @@ -1667,7 +1666,7 @@ static int sdhci_esdhc_runtime_suspend(struct device *dev) clk_disable_unprepare(imx_data->clk_ahb); if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_remove_request(&imx_data->pm_qos_req); + cpu_latency_qos_remove_request(&imx_data->pm_qos_req); return ret; } @@ -1680,8 +1679,7 @@ static int sdhci_esdhc_runtime_resume(struct device *dev) int err; if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_add_request(&imx_data->pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&imx_data->pm_qos_req, 0); err = clk_prepare_enable(imx_data->clk_ahb); if (err) @@ -1714,7 +1712,7 @@ static int sdhci_esdhc_runtime_resume(struct device *dev) clk_disable_unprepare(imx_data->clk_ahb); remove_pm_qos_request: if (imx_data->socdata->flags & ESDHC_FLAG_PMQOS) - pm_qos_remove_request(&imx_data->pm_qos_req); + cpu_latency_qos_remove_request(&imx_data->pm_qos_req); return err; } #endif From 81e95ad74154232f0cda38e03e135cf1a0984888 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:24:36 +0100 Subject: [PATCH 20/30] drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/update/remove_request() instead of pm_qos_add/update/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Acked-by: Jeff Kirsher Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/net/ethernet/intel/e1000e/netdev.c | 13 ++++++------- drivers/net/wireless/ath/ath10k/core.c | 4 ++-- drivers/net/wireless/intel/ipw2x00/ipw2100.c | 10 +++++----- 3 files changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index db4ea58bac82..0f02c7a5ee9b 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -3280,10 +3280,10 @@ static void e1000_configure_rx(struct e1000_adapter *adapter) dev_info(&adapter->pdev->dev, "Some CPU C-states have been disabled in order to enable jumbo frames\n"); - pm_qos_update_request(&adapter->pm_qos_req, lat); + cpu_latency_qos_update_request(&adapter->pm_qos_req, lat); } else { - pm_qos_update_request(&adapter->pm_qos_req, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(&adapter->pm_qos_req, + PM_QOS_DEFAULT_VALUE); } /* Enable Receives */ @@ -4636,8 +4636,7 @@ int e1000e_open(struct net_device *netdev) e1000_update_mng_vlan(adapter); /* DMA latency requirement to workaround jumbo issue */ - pm_qos_add_request(&adapter->pm_qos_req, PM_QOS_CPU_DMA_LATENCY, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(&adapter->pm_qos_req, PM_QOS_DEFAULT_VALUE); /* before we allocate an interrupt, we must be ready to handle it. * Setting DEBUG_SHIRQ in the kernel makes it fire an interrupt @@ -4679,7 +4678,7 @@ int e1000e_open(struct net_device *netdev) return 0; err_req_irq: - pm_qos_remove_request(&adapter->pm_qos_req); + cpu_latency_qos_remove_request(&adapter->pm_qos_req); e1000e_release_hw_control(adapter); e1000_power_down_phy(adapter); e1000e_free_rx_resources(adapter->rx_ring); @@ -4743,7 +4742,7 @@ int e1000e_close(struct net_device *netdev) !test_bit(__E1000_TESTING, &adapter->state)) e1000e_release_hw_control(adapter); - pm_qos_remove_request(&adapter->pm_qos_req); + cpu_latency_qos_remove_request(&adapter->pm_qos_req); pm_runtime_put_sync(&pdev->dev); diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c index 5ec16ce19b69..a202a4eea76a 100644 --- a/drivers/net/wireless/ath/ath10k/core.c +++ b/drivers/net/wireless/ath/ath10k/core.c @@ -1052,11 +1052,11 @@ static int ath10k_download_fw(struct ath10k *ar) } memset(&latency_qos, 0, sizeof(latency_qos)); - pm_qos_add_request(&latency_qos, PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&latency_qos, 0); ret = ath10k_bmi_fast_download(ar, address, data, data_len); - pm_qos_remove_request(&latency_qos); + cpu_latency_qos_remove_request(&latency_qos); return ret; } diff --git a/drivers/net/wireless/intel/ipw2x00/ipw2100.c b/drivers/net/wireless/intel/ipw2x00/ipw2100.c index 536cd729c086..5dfcce77d094 100644 --- a/drivers/net/wireless/intel/ipw2x00/ipw2100.c +++ b/drivers/net/wireless/intel/ipw2x00/ipw2100.c @@ -1730,7 +1730,7 @@ static int ipw2100_up(struct ipw2100_priv *priv, int deferred) /* the ipw2100 hardware really doesn't want power management delays * longer than 175usec */ - pm_qos_update_request(&ipw2100_pm_qos_req, 175); + cpu_latency_qos_update_request(&ipw2100_pm_qos_req, 175); /* If the interrupt is enabled, turn it off... */ spin_lock_irqsave(&priv->low_lock, flags); @@ -1875,7 +1875,8 @@ static void ipw2100_down(struct ipw2100_priv *priv) ipw2100_disable_interrupts(priv); spin_unlock_irqrestore(&priv->low_lock, flags); - pm_qos_update_request(&ipw2100_pm_qos_req, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(&ipw2100_pm_qos_req, + PM_QOS_DEFAULT_VALUE); /* We have to signal any supplicant if we are disassociating */ if (associated) @@ -6566,8 +6567,7 @@ static int __init ipw2100_init(void) printk(KERN_INFO DRV_NAME ": %s, %s\n", DRV_DESCRIPTION, DRV_VERSION); printk(KERN_INFO DRV_NAME ": %s\n", DRV_COPYRIGHT); - pm_qos_add_request(&ipw2100_pm_qos_req, PM_QOS_CPU_DMA_LATENCY, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(&ipw2100_pm_qos_req, PM_QOS_DEFAULT_VALUE); ret = pci_register_driver(&ipw2100_pci_driver); if (ret) @@ -6594,7 +6594,7 @@ static void __exit ipw2100_exit(void) &driver_attr_debug_level); #endif pci_unregister_driver(&ipw2100_pci_driver); - pm_qos_remove_request(&ipw2100_pm_qos_req); + cpu_latency_qos_remove_request(&ipw2100_pm_qos_req); } module_init(ipw2100_init); From c4c632e9074b62dbe3e756accb3bd6be13fcb61a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:26:04 +0100 Subject: [PATCH 21/30] drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/remove_request() instead of pm_qos_add/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/spi/spi-fsl-qspi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-fsl-qspi.c b/drivers/spi/spi-fsl-qspi.c index e8a499cd1f13..02e5cba0a5bb 100644 --- a/drivers/spi/spi-fsl-qspi.c +++ b/drivers/spi/spi-fsl-qspi.c @@ -484,7 +484,7 @@ static int fsl_qspi_clk_prep_enable(struct fsl_qspi *q) } if (needs_wakeup_wait_mode(q)) - pm_qos_add_request(&q->pm_qos_req, PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&q->pm_qos_req, 0); return 0; } @@ -492,7 +492,7 @@ static int fsl_qspi_clk_prep_enable(struct fsl_qspi *q) static void fsl_qspi_clk_disable_unprep(struct fsl_qspi *q) { if (needs_wakeup_wait_mode(q)) - pm_qos_remove_request(&q->pm_qos_req); + cpu_latency_qos_remove_request(&q->pm_qos_req); clk_disable_unprepare(q->clk); clk_disable_unprepare(q->clk_en); From 01d2b1898c7c95863e5c3eeabb3d5688eeaefef9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:27:04 +0100 Subject: [PATCH 22/30] drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/update/remove_request() instead of pm_qos_add/update/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Acked-by: Greg Kroah-Hartman Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/tty/serial/8250/8250_omap.c | 7 +++---- drivers/tty/serial/omap-serial.c | 9 ++++----- 2 files changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 19f8d2f9e7ba..76fe72bfb8bb 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -569,7 +569,7 @@ static void omap8250_uart_qos_work(struct work_struct *work) struct omap8250_priv *priv; priv = container_of(work, struct omap8250_priv, qos_work); - pm_qos_update_request(&priv->pm_qos_request, priv->latency); + cpu_latency_qos_update_request(&priv->pm_qos_request, priv->latency); } #ifdef CONFIG_SERIAL_8250_DMA @@ -1224,8 +1224,7 @@ static int omap8250_probe(struct platform_device *pdev) priv->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; priv->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; - pm_qos_add_request(&priv->pm_qos_request, PM_QOS_CPU_DMA_LATENCY, - priv->latency); + cpu_latency_qos_add_request(&priv->pm_qos_request, priv->latency); INIT_WORK(&priv->qos_work, omap8250_uart_qos_work); spin_lock_init(&priv->rx_dma_lock); @@ -1295,7 +1294,7 @@ static int omap8250_remove(struct platform_device *pdev) pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); serial8250_unregister_port(priv->line); - pm_qos_remove_request(&priv->pm_qos_request); + cpu_latency_qos_remove_request(&priv->pm_qos_request); device_init_wakeup(&pdev->dev, false); return 0; } diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index ce2558767eee..e0b720ac754b 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -831,7 +831,7 @@ static void serial_omap_uart_qos_work(struct work_struct *work) struct uart_omap_port *up = container_of(work, struct uart_omap_port, qos_work); - pm_qos_update_request(&up->pm_qos_request, up->latency); + cpu_latency_qos_update_request(&up->pm_qos_request, up->latency); } static void @@ -1724,8 +1724,7 @@ static int serial_omap_probe(struct platform_device *pdev) up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; - pm_qos_add_request(&up->pm_qos_request, - PM_QOS_CPU_DMA_LATENCY, up->latency); + cpu_latency_qos_add_request(&up->pm_qos_request, up->latency); INIT_WORK(&up->qos_work, serial_omap_uart_qos_work); platform_set_drvdata(pdev, up); @@ -1759,7 +1758,7 @@ static int serial_omap_probe(struct platform_device *pdev) pm_runtime_dont_use_autosuspend(&pdev->dev); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); - pm_qos_remove_request(&up->pm_qos_request); + cpu_latency_qos_remove_request(&up->pm_qos_request); device_init_wakeup(up->dev, false); err_rs485: err_port_line: @@ -1777,7 +1776,7 @@ static int serial_omap_remove(struct platform_device *dev) pm_runtime_dont_use_autosuspend(up->dev); pm_runtime_put_sync(up->dev); pm_runtime_disable(up->dev); - pm_qos_remove_request(&up->pm_qos_request); + cpu_latency_qos_remove_request(&up->pm_qos_request); device_init_wakeup(&dev->dev, false); return 0; From 77b352456941e871ea6da01dcd65ddf796313b54 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:28:44 +0100 Subject: [PATCH 23/30] drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/remove_request() instead of pm_qos_add/remove_request(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- drivers/usb/chipidea/ci_hdrc_imx.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c index d8e7eb2f97b9..a479af3ae31d 100644 --- a/drivers/usb/chipidea/ci_hdrc_imx.c +++ b/drivers/usb/chipidea/ci_hdrc_imx.c @@ -393,8 +393,7 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev) } if (pdata.flags & CI_HDRC_PMQOS) - pm_qos_add_request(&data->pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&data->pm_qos_req, 0); ret = imx_get_clks(dev); if (ret) @@ -478,7 +477,7 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev) /* don't overwrite original ret (cf. EPROBE_DEFER) */ regulator_disable(data->hsic_pad_regulator); if (pdata.flags & CI_HDRC_PMQOS) - pm_qos_remove_request(&data->pm_qos_req); + cpu_latency_qos_remove_request(&data->pm_qos_req); data->ci_pdev = NULL; return ret; } @@ -499,7 +498,7 @@ static int ci_hdrc_imx_remove(struct platform_device *pdev) if (data->ci_pdev) { imx_disable_unprepare_clks(&pdev->dev); if (data->plat_data->flags & CI_HDRC_PMQOS) - pm_qos_remove_request(&data->pm_qos_req); + cpu_latency_qos_remove_request(&data->pm_qos_req); if (data->hsic_pad_regulator) regulator_disable(data->hsic_pad_regulator); } @@ -527,7 +526,7 @@ static int __maybe_unused imx_controller_suspend(struct device *dev) imx_disable_unprepare_clks(dev); if (data->plat_data->flags & CI_HDRC_PMQOS) - pm_qos_remove_request(&data->pm_qos_req); + cpu_latency_qos_remove_request(&data->pm_qos_req); data->in_lpm = true; @@ -547,8 +546,7 @@ static int __maybe_unused imx_controller_resume(struct device *dev) } if (data->plat_data->flags & CI_HDRC_PMQOS) - pm_qos_add_request(&data->pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, 0); + cpu_latency_qos_add_request(&data->pm_qos_req, 0); ret = imx_prepare_enable_clks(dev); if (ret) From 5371a79be97caacf842282fcb309675c975f428f Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:34:15 +0100 Subject: [PATCH 24/30] sound: Call cpu_latency_qos_*() instead of pm_qos_*() Call cpu_latency_qos_add/update/remove_request() and cpu_latency_qos_request_active() instead of pm_qos_add/update/remove_request() and pm_qos_request_active(), respectively, because the latter are going to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Acked-by: Mark Brown Acked-by: Takashi Iwai Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- sound/core/pcm_native.c | 14 +++++++------- sound/soc/intel/atom/sst/sst.c | 5 ++--- sound/soc/intel/atom/sst/sst_loader.c | 4 ++-- sound/soc/ti/omap-dmic.c | 7 ++++--- sound/soc/ti/omap-mcbsp.c | 16 ++++++++-------- sound/soc/ti/omap-mcpdm.c | 16 ++++++++-------- 6 files changed, 31 insertions(+), 31 deletions(-) diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 336406bcb59e..151bac1bbd0b 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -748,11 +748,11 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream, snd_pcm_timer_resolution_change(substream); snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP); - if (pm_qos_request_active(&substream->latency_pm_qos_req)) - pm_qos_remove_request(&substream->latency_pm_qos_req); + if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req)) + cpu_latency_qos_remove_request(&substream->latency_pm_qos_req); if ((usecs = period_to_usecs(runtime)) >= 0) - pm_qos_add_request(&substream->latency_pm_qos_req, - PM_QOS_CPU_DMA_LATENCY, usecs); + cpu_latency_qos_add_request(&substream->latency_pm_qos_req, + usecs); return 0; _error: /* hardware might be unusable from this time, @@ -821,7 +821,7 @@ static int snd_pcm_hw_free(struct snd_pcm_substream *substream) return -EBADFD; result = do_hw_free(substream); snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN); - pm_qos_remove_request(&substream->latency_pm_qos_req); + cpu_latency_qos_remove_request(&substream->latency_pm_qos_req); return result; } @@ -2598,8 +2598,8 @@ void snd_pcm_release_substream(struct snd_pcm_substream *substream) substream->ops->close(substream); substream->hw_opened = 0; } - if (pm_qos_request_active(&substream->latency_pm_qos_req)) - pm_qos_remove_request(&substream->latency_pm_qos_req); + if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req)) + cpu_latency_qos_remove_request(&substream->latency_pm_qos_req); if (substream->pcm_release) { substream->pcm_release(substream); substream->pcm_release = NULL; diff --git a/sound/soc/intel/atom/sst/sst.c b/sound/soc/intel/atom/sst/sst.c index 68bcec5241f7..d6563985e008 100644 --- a/sound/soc/intel/atom/sst/sst.c +++ b/sound/soc/intel/atom/sst/sst.c @@ -325,8 +325,7 @@ int sst_context_init(struct intel_sst_drv *ctx) ret = -ENOMEM; goto do_free_mem; } - pm_qos_add_request(ctx->qos, PM_QOS_CPU_DMA_LATENCY, - PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(ctx->qos, PM_QOS_DEFAULT_VALUE); dev_dbg(ctx->dev, "Requesting FW %s now...\n", ctx->firmware_name); ret = request_firmware_nowait(THIS_MODULE, true, ctx->firmware_name, @@ -364,7 +363,7 @@ void sst_context_cleanup(struct intel_sst_drv *ctx) sysfs_remove_group(&ctx->dev->kobj, &sst_fw_version_attr_group); flush_scheduled_work(); destroy_workqueue(ctx->post_msg_wq); - pm_qos_remove_request(ctx->qos); + cpu_latency_qos_remove_request(ctx->qos); kfree(ctx->fw_sg_list.src); kfree(ctx->fw_sg_list.dst); ctx->fw_sg_list.list_len = 0; diff --git a/sound/soc/intel/atom/sst/sst_loader.c b/sound/soc/intel/atom/sst/sst_loader.c index ce11c36848c4..9b0e3739c738 100644 --- a/sound/soc/intel/atom/sst/sst_loader.c +++ b/sound/soc/intel/atom/sst/sst_loader.c @@ -412,7 +412,7 @@ int sst_load_fw(struct intel_sst_drv *sst_drv_ctx) return -ENOMEM; /* Prevent C-states beyond C6 */ - pm_qos_update_request(sst_drv_ctx->qos, 0); + cpu_latency_qos_update_request(sst_drv_ctx->qos, 0); sst_drv_ctx->sst_state = SST_FW_LOADING; @@ -442,7 +442,7 @@ int sst_load_fw(struct intel_sst_drv *sst_drv_ctx) restore: /* Re-enable Deeper C-states beyond C6 */ - pm_qos_update_request(sst_drv_ctx->qos, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_update_request(sst_drv_ctx->qos, PM_QOS_DEFAULT_VALUE); sst_free_block(sst_drv_ctx, block); dev_dbg(sst_drv_ctx->dev, "fw load successful!!!\n"); diff --git a/sound/soc/ti/omap-dmic.c b/sound/soc/ti/omap-dmic.c index 3f226be123d4..913579c43e9d 100644 --- a/sound/soc/ti/omap-dmic.c +++ b/sound/soc/ti/omap-dmic.c @@ -112,7 +112,7 @@ static void omap_dmic_dai_shutdown(struct snd_pcm_substream *substream, mutex_lock(&dmic->mutex); - pm_qos_remove_request(&dmic->pm_qos_req); + cpu_latency_qos_remove_request(&dmic->pm_qos_req); if (!dai->active) dmic->active = 0; @@ -230,8 +230,9 @@ static int omap_dmic_dai_prepare(struct snd_pcm_substream *substream, struct omap_dmic *dmic = snd_soc_dai_get_drvdata(dai); u32 ctrl; - if (pm_qos_request_active(&dmic->pm_qos_req)) - pm_qos_update_request(&dmic->pm_qos_req, dmic->latency); + if (cpu_latency_qos_request_active(&dmic->pm_qos_req)) + cpu_latency_qos_update_request(&dmic->pm_qos_req, + dmic->latency); /* Configure uplink threshold */ omap_dmic_write(dmic, OMAP_DMIC_FIFO_CTRL_REG, dmic->threshold); diff --git a/sound/soc/ti/omap-mcbsp.c b/sound/soc/ti/omap-mcbsp.c index 26b503bbdb5f..302d5c493c29 100644 --- a/sound/soc/ti/omap-mcbsp.c +++ b/sound/soc/ti/omap-mcbsp.c @@ -836,10 +836,10 @@ static void omap_mcbsp_dai_shutdown(struct snd_pcm_substream *substream, int stream2 = tx ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK; if (mcbsp->latency[stream2]) - pm_qos_update_request(&mcbsp->pm_qos_req, - mcbsp->latency[stream2]); + cpu_latency_qos_update_request(&mcbsp->pm_qos_req, + mcbsp->latency[stream2]); else if (mcbsp->latency[stream1]) - pm_qos_remove_request(&mcbsp->pm_qos_req); + cpu_latency_qos_remove_request(&mcbsp->pm_qos_req); mcbsp->latency[stream1] = 0; @@ -863,10 +863,10 @@ static int omap_mcbsp_dai_prepare(struct snd_pcm_substream *substream, if (!latency || mcbsp->latency[stream1] < latency) latency = mcbsp->latency[stream1]; - if (pm_qos_request_active(pm_qos_req)) - pm_qos_update_request(pm_qos_req, latency); + if (cpu_latency_qos_request_active(pm_qos_req)) + cpu_latency_qos_update_request(pm_qos_req, latency); else if (latency) - pm_qos_add_request(pm_qos_req, PM_QOS_CPU_DMA_LATENCY, latency); + cpu_latency_qos_add_request(pm_qos_req, latency); return 0; } @@ -1434,8 +1434,8 @@ static int asoc_mcbsp_remove(struct platform_device *pdev) if (mcbsp->pdata->ops && mcbsp->pdata->ops->free) mcbsp->pdata->ops->free(mcbsp->id); - if (pm_qos_request_active(&mcbsp->pm_qos_req)) - pm_qos_remove_request(&mcbsp->pm_qos_req); + if (cpu_latency_qos_request_active(&mcbsp->pm_qos_req)) + cpu_latency_qos_remove_request(&mcbsp->pm_qos_req); if (mcbsp->pdata->buffer_size) sysfs_remove_group(&mcbsp->dev->kobj, &additional_attr_group); diff --git a/sound/soc/ti/omap-mcpdm.c b/sound/soc/ti/omap-mcpdm.c index a726cd7a8252..d7ac4df6f2d9 100644 --- a/sound/soc/ti/omap-mcpdm.c +++ b/sound/soc/ti/omap-mcpdm.c @@ -281,10 +281,10 @@ static void omap_mcpdm_dai_shutdown(struct snd_pcm_substream *substream, } if (mcpdm->latency[stream2]) - pm_qos_update_request(&mcpdm->pm_qos_req, - mcpdm->latency[stream2]); + cpu_latency_qos_update_request(&mcpdm->pm_qos_req, + mcpdm->latency[stream2]); else if (mcpdm->latency[stream1]) - pm_qos_remove_request(&mcpdm->pm_qos_req); + cpu_latency_qos_remove_request(&mcpdm->pm_qos_req); mcpdm->latency[stream1] = 0; @@ -386,10 +386,10 @@ static int omap_mcpdm_prepare(struct snd_pcm_substream *substream, if (!latency || mcpdm->latency[stream1] < latency) latency = mcpdm->latency[stream1]; - if (pm_qos_request_active(pm_qos_req)) - pm_qos_update_request(pm_qos_req, latency); + if (cpu_latency_qos_request_active(pm_qos_req)) + cpu_latency_qos_update_request(pm_qos_req, latency); else if (latency) - pm_qos_add_request(pm_qos_req, PM_QOS_CPU_DMA_LATENCY, latency); + cpu_latency_qos_add_request(pm_qos_req, latency); if (!omap_mcpdm_active(mcpdm)) { omap_mcpdm_start(mcpdm); @@ -451,8 +451,8 @@ static int omap_mcpdm_remove(struct snd_soc_dai *dai) free_irq(mcpdm->irq, (void *)mcpdm); pm_runtime_disable(mcpdm->dev); - if (pm_qos_request_active(&mcpdm->pm_qos_req)) - pm_qos_remove_request(&mcpdm->pm_qos_req); + if (cpu_latency_qos_request_active(&mcpdm->pm_qos_req)) + cpu_latency_qos_remove_request(&mcpdm->pm_qos_req); return 0; } From 67b06ba01857ed077e1a66bfa139156e7c68bab2 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:35:04 +0100 Subject: [PATCH 25/30] PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions Drop the PM QoS classes enum including PM_QOS_CPU_DMA_LATENCY, drop the wrappers around pm_qos_request(), pm_qos_request_active(), and pm_qos_add/update/remove_request() introduced previously, rename these functions, respectively, to cpu_latency_qos_limit(), cpu_latency_qos_request_active(), and cpu_latency_qos_add/update/remove_request(), and update their kerneldoc comments. [While at it, drop some useless comments from these functions.] No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 47 +++----------------- kernel/power/qos.c | 98 +++++++++++++++++++++--------------------- 2 files changed, 54 insertions(+), 91 deletions(-) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 63d39e66f95d..e0ca4d780457 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -9,14 +9,6 @@ #include #include -enum { - PM_QOS_RESERVED = 0, - PM_QOS_CPU_DMA_LATENCY, - - /* insert new class ID */ - PM_QOS_NUM_CLASSES, -}; - enum pm_qos_flags_status { PM_QOS_FLAGS_UNDEFINED = -1, PM_QOS_FLAGS_NONE, @@ -144,40 +136,11 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, struct pm_qos_flags_request *req, enum pm_qos_req_action action, s32 val); -void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, - s32 value); -void pm_qos_update_request(struct pm_qos_request *req, - s32 new_value); -void pm_qos_remove_request(struct pm_qos_request *req); -s32 pm_qos_request(int pm_qos_class); -int pm_qos_request_active(struct pm_qos_request *req); - -static inline void cpu_latency_qos_add_request(struct pm_qos_request *req, - s32 value) -{ - pm_qos_add_request(req, PM_QOS_CPU_DMA_LATENCY, value); -} - -static inline void cpu_latency_qos_update_request(struct pm_qos_request *req, - s32 new_value) -{ - pm_qos_update_request(req, new_value); -} - -static inline void cpu_latency_qos_remove_request(struct pm_qos_request *req) -{ - pm_qos_remove_request(req); -} - -static inline bool cpu_latency_qos_request_active(struct pm_qos_request *req) -{ - return pm_qos_request_active(req); -} - -static inline s32 cpu_latency_qos_limit(void) -{ - return pm_qos_request(PM_QOS_CPU_DMA_LATENCY); -} +s32 cpu_latency_qos_limit(void); +bool cpu_latency_qos_request_active(struct pm_qos_request *req); +void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value); +void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value); +void cpu_latency_qos_remove_request(struct pm_qos_request *req); #ifdef CONFIG_PM enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 7bb55aca03bb..7374c76f409a 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -230,21 +230,25 @@ static struct pm_qos_constraints cpu_latency_constraints = { }; /** - * pm_qos_request - returns current system wide qos expectation - * @pm_qos_class: Ignored. - * - * This function returns the current target value. + * cpu_latency_qos_limit - Return current system-wide CPU latency QoS limit. */ -s32 pm_qos_request(int pm_qos_class) +s32 cpu_latency_qos_limit(void) { return pm_qos_read_value(&cpu_latency_constraints); } -int pm_qos_request_active(struct pm_qos_request *req) +/** + * cpu_latency_qos_request_active - Check the given PM QoS request. + * @req: PM QoS request to check. + * + * Return: 'true' if @req has been added to the CPU latency QoS list, 'false' + * otherwise. + */ +bool cpu_latency_qos_request_active(struct pm_qos_request *req) { return req->qos == &cpu_latency_constraints; } -EXPORT_SYMBOL_GPL(pm_qos_request_active); +EXPORT_SYMBOL_GPL(cpu_latency_qos_request_active); static void cpu_latency_qos_apply(struct pm_qos_request *req, enum pm_qos_req_action action, s32 value) @@ -255,25 +259,24 @@ static void cpu_latency_qos_apply(struct pm_qos_request *req, } /** - * pm_qos_add_request - inserts new qos request into the list - * @req: pointer to a preallocated handle - * @pm_qos_class: Ignored. - * @value: defines the qos request + * cpu_latency_qos_add_request - Add new CPU latency QoS request. + * @req: Pointer to a preallocated handle. + * @value: Requested constraint value. * - * This function inserts a new entry in the PM_QOS_CPU_DMA_LATENCY list of - * requested QoS performance characteristics. It recomputes the aggregate QoS - * expectations for the PM_QOS_CPU_DMA_LATENCY list and initializes the @req - * handle. Caller needs to save this handle for later use in updates and - * removal. + * Use @value to initialize the request handle pointed to by @req, insert it as + * a new entry to the CPU latency QoS list and recompute the effective QoS + * constraint for that list. + * + * Callers need to save the handle for later use in updates and removal of the + * QoS request represented by it. */ -void pm_qos_add_request(struct pm_qos_request *req, - int pm_qos_class, s32 value) +void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value) { - if (!req) /*guard against callers passing in null */ + if (!req) return; - if (pm_qos_request_active(req)) { - WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); + if (cpu_latency_qos_request_active(req)) { + WARN(1, KERN_ERR "%s called for already added request\n", __func__); return; } @@ -282,25 +285,24 @@ void pm_qos_add_request(struct pm_qos_request *req, req->qos = &cpu_latency_constraints; cpu_latency_qos_apply(req, PM_QOS_ADD_REQ, value); } -EXPORT_SYMBOL_GPL(pm_qos_add_request); +EXPORT_SYMBOL_GPL(cpu_latency_qos_add_request); /** - * pm_qos_update_request - modifies an existing qos request - * @req : handle to list element holding a pm_qos request to use - * @value: defines the qos request + * cpu_latency_qos_update_request - Modify existing CPU latency QoS request. + * @req : QoS request to update. + * @new_value: New requested constraint value. * - * Updates an existing qos request for the PM_QOS_CPU_DMA_LATENCY list along - * with updating the target PM_QOS_CPU_DMA_LATENCY value. - * - * Attempts are made to make this code callable on hot code paths. + * Use @new_value to update the QoS request represented by @req in the CPU + * latency QoS list along with updating the effective constraint value for that + * list. */ -void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) +void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value) { - if (!req) /*guard against callers passing in null */ + if (!req) return; - if (!pm_qos_request_active(req)) { - WARN(1, KERN_ERR "pm_qos_update_request() called for unknown object\n"); + if (!cpu_latency_qos_request_active(req)) { + WARN(1, KERN_ERR "%s called for unknown object\n", __func__); return; } @@ -311,24 +313,22 @@ void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) cpu_latency_qos_apply(req, PM_QOS_UPDATE_REQ, new_value); } -EXPORT_SYMBOL_GPL(pm_qos_update_request); +EXPORT_SYMBOL_GPL(cpu_latency_qos_update_request); /** - * pm_qos_remove_request - modifies an existing qos request - * @req: handle to request list element + * cpu_latency_qos_remove_request - Remove existing CPU latency QoS request. + * @req: QoS request to remove. * - * Will remove pm qos request from the list of constraints and - * recompute the current target value for PM_QOS_CPU_DMA_LATENCY. Call this - * on slow code paths. + * Remove the CPU latency QoS request represented by @req from the CPU latency + * QoS list along with updating the effective constraint value for that list. */ -void pm_qos_remove_request(struct pm_qos_request *req) +void cpu_latency_qos_remove_request(struct pm_qos_request *req) { - if (!req) /*guard against callers passing in null */ + if (!req) return; - /* silent return to keep pcm code cleaner */ - if (!pm_qos_request_active(req)) { - WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown object\n"); + if (!cpu_latency_qos_request_active(req)) { + WARN(1, KERN_ERR "%s called for unknown object\n", __func__); return; } @@ -337,7 +337,7 @@ void pm_qos_remove_request(struct pm_qos_request *req) cpu_latency_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } -EXPORT_SYMBOL_GPL(pm_qos_remove_request); +EXPORT_SYMBOL_GPL(cpu_latency_qos_remove_request); /* User space interface to the CPU latency QoS via misc device. */ @@ -349,7 +349,7 @@ static int cpu_latency_qos_open(struct inode *inode, struct file *filp) if (!req) return -ENOMEM; - pm_qos_add_request(req, PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE); + cpu_latency_qos_add_request(req, PM_QOS_DEFAULT_VALUE); filp->private_data = req; return 0; @@ -361,7 +361,7 @@ static int cpu_latency_qos_release(struct inode *inode, struct file *filp) filp->private_data = NULL; - pm_qos_remove_request(req); + cpu_latency_qos_remove_request(req); kfree(req); return 0; @@ -374,7 +374,7 @@ static ssize_t cpu_latency_qos_read(struct file *filp, char __user *buf, unsigned long flags; s32 value; - if (!req || !pm_qos_request_active(req)) + if (!req || !cpu_latency_qos_request_active(req)) return -EINVAL; spin_lock_irqsave(&pm_qos_lock, flags); @@ -400,7 +400,7 @@ static ssize_t cpu_latency_qos_write(struct file *filp, const char __user *buf, return ret; } - pm_qos_update_request(filp->private_data, value); + cpu_latency_qos_update_request(filp->private_data, value); return count; } From fe52de36dc5d60960230cabec88c357113d9c32a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:35:39 +0100 Subject: [PATCH 26/30] PM: QoS: Update file information comments Update the file information comments in include/linux/pm_qos.h and kernel/power/qos.c by adding titles along with copyright and authors information to them and changing the qos.c description to better reflect its contents (outdated information is dropped from it in particular). Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 15 +++++++++++---- kernel/power/qos.c | 34 ++++++++++++---------------------- 2 files changed, 23 insertions(+), 26 deletions(-) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index e0ca4d780457..df065db3f57a 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -1,10 +1,17 @@ /* SPDX-License-Identifier: GPL-2.0 */ +/* + * Definitions related to Power Management Quality of Service (PM QoS). + * + * Copyright (C) 2020 Intel Corporation + * + * Authors: + * Mark Gross + * Rafael J. Wysocki + */ + #ifndef _LINUX_PM_QOS_H #define _LINUX_PM_QOS_H -/* interface for the pm_qos_power infrastructure of the linux kernel. - * - * Mark Gross - */ + #include #include #include diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 7374c76f409a..ef73573db43d 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -1,31 +1,21 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * This module exposes the interface to kernel space for specifying - * QoS dependencies. It provides infrastructure for registration of: + * Power Management Quality of Service (PM QoS) support base. * - * Dependents on a QoS value : register requests - * Watchers of QoS value : get notified when target QoS value changes + * Copyright (C) 2020 Intel Corporation * - * This QoS design is best effort based. Dependents register their QoS needs. - * Watchers register to keep track of the current QoS needs of the system. + * Authors: + * Mark Gross + * Rafael J. Wysocki * - * There are 3 basic classes of QoS parameter: latency, timeout, throughput - * each have defined units: - * latency: usec - * timeout: usec <-- currently not used. - * throughput: kbs (kilo byte / sec) + * Provided here is an interface for specifying PM QoS dependencies. It allows + * entities depending on QoS constraints to register their requests which are + * aggregated as appropriate to produce effective constraints (target values) + * that can be monitored by entities needing to respect them, either by polling + * or through a built-in notification mechanism. * - * There are lists of pm_qos_objects each one wrapping requests, notifiers - * - * User mode requests on a QOS parameter register themselves to the - * subsystem by opening the device node /dev/... and writing there request to - * the node. As long as the process holds a file handle open to the node the - * client continues to be accounted for. Upon file release the usermode - * request is removed and a new qos target is computed. This way when the - * request that the application has is cleaned up when closes the file - * pointer or exits the pm_qos_object will get an opportunity to clean up. - * - * Mark Gross + * In addition to the basic functionality, more specific interfaces for managing + * global CPU latency QoS requests and frequency QoS requests are provided. */ /*#define DEBUG*/ From b8e6e27c626e60bb5708ce8c974b58c485c32ac7 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:36:35 +0100 Subject: [PATCH 27/30] Documentation: PM: QoS: Update to reflect previous code changes Update the PM QoS documentation to reflect the previous code changes regarding the removal of PM QoS classes and the CPU latency QoS API rework. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- Documentation/admin-guide/pm/cpuidle.rst | 73 ++++++++++---------- Documentation/power/pm_qos_interface.rst | 84 +++++++++++------------- 2 files changed, 74 insertions(+), 83 deletions(-) diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index 6a06dc473dd6..5605cc6f9560 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -583,20 +583,17 @@ Power Management Quality of Service for CPUs The power management quality of service (PM QoS) framework in the Linux kernel allows kernel code and user space processes to set constraints on various energy-efficiency features of the kernel to prevent performance from dropping -below a required level. The PM QoS constraints can be set globally, in -predefined categories referred to as PM QoS classes, or against individual -devices. +below a required level. CPU idle time management can be affected by PM QoS in two ways, through the -global constraint in the ``PM_QOS_CPU_DMA_LATENCY`` class and through the -resume latency constraints for individual CPUs. Kernel code (e.g. device -drivers) can set both of them with the help of special internal interfaces -provided by the PM QoS framework. User space can modify the former by opening -the :file:`cpu_dma_latency` special device file under :file:`/dev/` and writing -a binary value (interpreted as a signed 32-bit integer) to it. In turn, the -resume latency constraint for a CPU can be modified by user space by writing a -string (representing a signed 32-bit integer) to the -:file:`power/pm_qos_resume_latency_us` file under +global CPU latency limit and through the resume latency constraints for +individual CPUs. Kernel code (e.g. device drivers) can set both of them with +the help of special internal interfaces provided by the PM QoS framework. User +space can modify the former by opening the :file:`cpu_dma_latency` special +device file under :file:`/dev/` and writing a binary value (interpreted as a +signed 32-bit integer) to it. In turn, the resume latency constraint for a CPU +can be modified from user space by writing a string (representing a signed +32-bit integer) to the :file:`power/pm_qos_resume_latency_us` file under :file:`/sys/devices/system/cpu/cpu/` in ``sysfs``, where the CPU number ```` is allocated at the system initialization time. Negative values will be rejected in both cases and, also in both cases, the written integer @@ -605,32 +602,34 @@ number will be interpreted as a requested PM QoS constraint in microseconds. The requested value is not automatically applied as a new constraint, however, as it may be less restrictive (greater in this particular case) than another constraint previously requested by someone else. For this reason, the PM QoS -framework maintains a list of requests that have been made so far in each -global class and for each device, aggregates them and applies the effective -(minimum in this particular case) value as the new constraint. +framework maintains a list of requests that have been made so far for the +global CPU latency limit and for each individual CPU, aggregates them and +applies the effective (minimum in this particular case) value as the new +constraint. In fact, opening the :file:`cpu_dma_latency` special device file causes a new -PM QoS request to be created and added to the priority list of requests in the -``PM_QOS_CPU_DMA_LATENCY`` class and the file descriptor coming from the -"open" operation represents that request. If that file descriptor is then -used for writing, the number written to it will be associated with the PM QoS -request represented by it as a new requested constraint value. Next, the -priority list mechanism will be used to determine the new effective value of -the entire list of requests and that effective value will be set as a new -constraint. Thus setting a new requested constraint value will only change the -real constraint if the effective "list" value is affected by it. In particular, -for the ``PM_QOS_CPU_DMA_LATENCY`` class it only affects the real constraint if -it is the minimum of the requested constraints in the list. The process holding -a file descriptor obtained by opening the :file:`cpu_dma_latency` special device -file controls the PM QoS request associated with that file descriptor, but it -controls this particular PM QoS request only. +PM QoS request to be created and added to a global priority list of CPU latency +limit requests and the file descriptor coming from the "open" operation +represents that request. If that file descriptor is then used for writing, the +number written to it will be associated with the PM QoS request represented by +it as a new requested limit value. Next, the priority list mechanism will be +used to determine the new effective value of the entire list of requests and +that effective value will be set as a new CPU latency limit. Thus requesting a +new limit value will only change the real limit if the effective "list" value is +affected by it, which is the case if it is the minimum of the requested values +in the list. + +The process holding a file descriptor obtained by opening the +:file:`cpu_dma_latency` special device file controls the PM QoS request +associated with that file descriptor, but it controls this particular PM QoS +request only. Closing the :file:`cpu_dma_latency` special device file or, more precisely, the file descriptor obtained while opening it, causes the PM QoS request associated -with that file descriptor to be removed from the ``PM_QOS_CPU_DMA_LATENCY`` -class priority list and destroyed. If that happens, the priority list mechanism -will be used, again, to determine the new effective value for the whole list -and that value will become the new real constraint. +with that file descriptor to be removed from the global priority list of CPU +latency limit requests and destroyed. If that happens, the priority list +mechanism will be used again, to determine the new effective value for the whole +list and that value will become the new limit. In turn, for each CPU there is one resume latency PM QoS request associated with the :file:`power/pm_qos_resume_latency_us` file under @@ -647,10 +646,10 @@ CPU in question every time the list of requests is updated this way or another (there may be other requests coming from kernel code in that list). CPU idle time governors are expected to regard the minimum of the global -effective ``PM_QOS_CPU_DMA_LATENCY`` class constraint and the effective -resume latency constraint for the given CPU as the upper limit for the exit -latency of the idle states they can select for that CPU. They should never -select any idle states with exit latency beyond that limit. +(effective) CPU latency limit and the effective resume latency constraint for +the given CPU as the upper limit for the exit latency of the idle states that +they are allowed to select for that CPU. They should never select any idle +states with exit latency beyond that limit. Idle States Control Via Kernel Command Line diff --git a/Documentation/power/pm_qos_interface.rst b/Documentation/power/pm_qos_interface.rst index 0d62d506caf0..064f668fbdab 100644 --- a/Documentation/power/pm_qos_interface.rst +++ b/Documentation/power/pm_qos_interface.rst @@ -7,86 +7,78 @@ performance expectations by drivers, subsystems and user space applications on one of the parameters. Two different PM QoS frameworks are available: -1. PM QoS classes for cpu_dma_latency +1. CPU latency QoS. 2. The per-device PM QoS framework provides the API to manage the per-device latency constraints and PM QoS flags. -Each parameters have defined units: - - * latency: usec - * timeout: usec - * throughput: kbs (kilo bit / sec) - * memory bandwidth: mbs (mega bit / sec) +The latency unit used in the PM QoS framework is the microsecond (usec). 1. PM QoS framework =================== -The infrastructure exposes multiple misc device nodes one per implemented -parameter. The set of parameters implement is defined by pm_qos_power_init() -and pm_qos_params.h. This is done because having the available parameters -being runtime configurable or changeable from a driver was seen as too easy to -abuse. +A global list of CPU latency QoS requests is maintained along with an aggregated +(effective) target value. The aggregated target value is updated with changes +to the request list or elements of the list. For CPU latency QoS, the +aggregated target value is simply the min of the request values held in the list +elements. -For each parameter a list of performance requests is maintained along with -an aggregated target value. The aggregated target value is updated with -changes to the request list or elements of the list. Typically the -aggregated target value is simply the max or min of the request values held -in the parameter list elements. Note: the aggregated target value is implemented as an atomic variable so that reading the aggregated value does not require any locking mechanism. +From kernel space the use of this interface is simple: -From kernel mode the use of this interface is simple: +void cpu_latency_qos_add_request(handle, target_value): + Will insert an element into the CPU latency QoS list with the target value. + Upon change to this list the new target is recomputed and any registered + notifiers are called only if the target value is now different. + Clients of PM QoS need to save the returned handle for future use in other + PM QoS API functions. -void pm_qos_add_request(handle, param_class, target_value): - Will insert an element into the list for that identified PM QoS class with the - target value. Upon change to this list the new target is recomputed and any - registered notifiers are called only if the target value is now different. - Clients of pm_qos need to save the returned handle for future use in other - pm_qos API functions. - -void pm_qos_update_request(handle, new_target_value): +void cpu_latency_qos_update_request(handle, new_target_value): Will update the list element pointed to by the handle with the new target value and recompute the new aggregated target, calling the notification tree if the target is changed. -void pm_qos_remove_request(handle): +void cpu_latency_qos_remove_request(handle): Will remove the element. After removal it will update the aggregate target and call the notification tree if the target was changed as a result of removing the request. -int pm_qos_request(param_class): - Returns the aggregated value for a given PM QoS class. +int cpu_latency_qos_limit(): + Returns the aggregated value for the CPU latency QoS. -int pm_qos_request_active(handle): - Returns if the request is still active, i.e. it has not been removed from a - PM QoS class constraints list. +int cpu_latency_qos_request_active(handle): + Returns if the request is still active, i.e. it has not been removed from the + CPU latency QoS list. -int pm_qos_add_notifier(param_class, notifier): - Adds a notification callback function to the PM QoS class. The callback is - called when the aggregated value for the PM QoS class is changed. +int cpu_latency_qos_add_notifier(notifier): + Adds a notification callback function to the CPU latency QoS. The callback is + called when the aggregated value for the CPU latency QoS is changed. -int pm_qos_remove_notifier(int param_class, notifier): - Removes the notification callback function for the PM QoS class. +int cpu_latency_qos_remove_notifier(notifier): + Removes the notification callback function from the CPU latency QoS. -From user mode: +From user space: -Only processes can register a pm_qos request. To provide for automatic +The infrastructure exposes one device node, /dev/cpu_dma_latency, for the CPU +latency QoS. + +Only processes can register a PM QoS request. To provide for automatic cleanup of a process, the interface requires the process to register its -parameter requests in the following way: +parameter requests as follows. -To register the default pm_qos target for the specific parameter, the process -must open /dev/cpu_dma_latency +To register the default PM QoS target for the CPU latency QoS, the process must +open /dev/cpu_dma_latency. As long as the device node is held open that process has a registered request on the parameter. -To change the requested target value the process needs to write an s32 value to -the open device node. Alternatively the user mode program could write a hex -string for the value using 10 char long format e.g. "0x12345678". This -translates to a pm_qos_update_request call. +To change the requested target value, the process needs to write an s32 value to +the open device node. Alternatively, it can write a hex string for the value +using the 10 char long format e.g. "0x12345678". This translates to a +cpu_latency_qos_update_request() call. To remove the user mode request for a target value simply close the device node. From 814d51f8889bc4afa75f647eeffd5ff0a5620e8d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 12 Feb 2020 00:37:11 +0100 Subject: [PATCH 28/30] PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE Because cpuidle is the only user of the effective constraint coming from the CPU latency QoS, add #ifdef CONFIG_CPU_IDLE around that code to avoid building it unnecessarily. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Amit Kucheria Tested-by: Amit Kucheria --- include/linux/pm_qos.h | 13 +++++++++++++ kernel/power/qos.c | 2 ++ 2 files changed, 15 insertions(+) diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index df065db3f57a..4a69d4af3ff8 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -143,11 +143,24 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, struct pm_qos_flags_request *req, enum pm_qos_req_action action, s32 val); +#ifdef CONFIG_CPU_IDLE s32 cpu_latency_qos_limit(void); bool cpu_latency_qos_request_active(struct pm_qos_request *req); void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value); void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value); void cpu_latency_qos_remove_request(struct pm_qos_request *req); +#else +static inline s32 cpu_latency_qos_limit(void) { return INT_MAX; } +static inline bool cpu_latency_qos_request_active(struct pm_qos_request *req) +{ + return false; +} +static inline void cpu_latency_qos_add_request(struct pm_qos_request *req, + s32 value) {} +static inline void cpu_latency_qos_update_request(struct pm_qos_request *req, + s32 new_value) {} +static inline void cpu_latency_qos_remove_request(struct pm_qos_request *req) {} +#endif #ifdef CONFIG_PM enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index ef73573db43d..32927682bcc4 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -209,6 +209,7 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, return prev_value != curr_value; } +#ifdef CONFIG_CPU_IDLE /* Definitions related to the CPU latency QoS. */ static struct pm_qos_constraints cpu_latency_constraints = { @@ -421,6 +422,7 @@ static int __init cpu_latency_qos_init(void) return ret; } late_initcall(cpu_latency_qos_init); +#endif /* CONFIG_CPU_IDLE */ /* Definitions related to the frequency QoS below. */ From 3c87402771f2bc38ee92eb506bb58e4fc4a5b8b9 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sun, 16 Feb 2020 20:54:21 -0800 Subject: [PATCH 29/30] Documentation: power: fix pm_qos_interface.rst format warning Fix Sphinx warnings by indenting the bullet list (and making it unnumbered). Documentation/power/pm_qos_interface.rst:12: WARNING: Unexpected indentation. Signed-off-by: Randy Dunlap Signed-off-by: Rafael J. Wysocki --- Documentation/power/pm_qos_interface.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/power/pm_qos_interface.rst b/Documentation/power/pm_qos_interface.rst index 064f668fbdab..69b0fe3e2542 100644 --- a/Documentation/power/pm_qos_interface.rst +++ b/Documentation/power/pm_qos_interface.rst @@ -7,8 +7,8 @@ performance expectations by drivers, subsystems and user space applications on one of the parameters. Two different PM QoS frameworks are available: -1. CPU latency QoS. -2. The per-device PM QoS framework provides the API to manage the + * CPU latency QoS. + * The per-device PM QoS framework provides the API to manage the per-device latency constraints and PM QoS flags. The latency unit used in the PM QoS framework is the microsecond (usec). From a534e924c58d2e7c07509521e87d059dd029dca1 Mon Sep 17 00:00:00 2001 From: Qian Cai Date: Tue, 25 Feb 2020 20:58:13 -0500 Subject: [PATCH 30/30] PM: QoS: annotate data races in pm_qos_*_value() The target_value field in struct pm_qos_constraints is used for lockless access to the effective constraint value of a given QoS list, so the readers of it cannot expect it to always reflect the most recent effective constraint value. However, they can and do expect it to be equal to a valid effective constraint value computed at a certain time in the past (event though it may not be the most recent one), so add READ|WRITE_ONCE() annotations around the target_value accesses to prevent the compiler from possibly causing that expectation to be unmet by generating code in an exceptionally convoluted way. Signed-off-by: Qian Cai [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki --- kernel/power/qos.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 32927682bcc4..db0bed2cae26 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -52,7 +52,7 @@ static DEFINE_SPINLOCK(pm_qos_lock); */ s32 pm_qos_read_value(struct pm_qos_constraints *c) { - return c->target_value; + return READ_ONCE(c->target_value); } static int pm_qos_get_value(struct pm_qos_constraints *c) @@ -75,7 +75,7 @@ static int pm_qos_get_value(struct pm_qos_constraints *c) static void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) { - c->target_value = value; + WRITE_ONCE(c->target_value, value); } /**