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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2020-03-30 14:45:57 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2020-03-30 14:45:57 +0200
commit8f1073ed8c18353ff2263294b243a315a71e9d48 (patch)
tree7f154d86c7f4494e5635d7b7289e942c26d5a5a6 /kernel/power
parent2f6bdb05e0b6adbcd05fae2aad7a9b6760fc7af6 (diff)
parenta534e924c58d2e7c07509521e87d059dd029dca1 (diff)
Merge branch 'pm-qos'
* pm-qos: (30 commits) PM: QoS: annotate data races in pm_qos_*_value() Documentation: power: fix pm_qos_interface.rst format warning PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE Documentation: PM: QoS: Update to reflect previous code changes PM: QoS: Update file information comments PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions sound: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*() drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*() x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*() cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request() PM: QoS: Add CPU latency QoS API wrappers PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h PM: QoS: Simplify definitions of CPU latency QoS trace events ...
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/qos.c559
1 files changed, 166 insertions, 393 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 83edf8698118..db0bed2cae26 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 <mgross@linux.intel.com>
+ * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
- * 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 <mgross@linux.intel.com>
+ * In addition to the basic functionality, more specific interfaces for managing
+ * global CPU latency QoS requests and frequency QoS requests are provided.
*/
/*#define DEBUG*/
@@ -54,56 +44,19 @@
* 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),
- .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,
-};
-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,
-};
-
-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,
-};
-
-/* 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)
{
- struct plist_node *node;
- int total_value = 0;
+ return READ_ONCE(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;
@@ -114,111 +67,42 @@ 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();
+ 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;
+ WRITE_ONCE(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
- * @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;
@@ -231,9 +115,8 @@ 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 */
@@ -252,16 +135,14 @@ 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;
}
/**
@@ -283,14 +164,12 @@ 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,
@@ -326,288 +205,180 @@ 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;
-}
-/**
- * pm_qos_request - returns current system wide qos expectation
- * @pm_qos_class: identification of which qos value is requested
- *
- * 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);
-}
-EXPORT_SYMBOL_GPL(pm_qos_request);
-
-int pm_qos_request_active(struct pm_qos_request *req)
-{
- return req->pm_qos_class != 0;
+ return prev_value != curr_value;
}
-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);
+#ifdef CONFIG_CPU_IDLE
+/* Definitions related to the CPU latency QoS. */
- 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);
-}
+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_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.
+ * cpu_latency_qos_limit - Return current system-wide CPU latency QoS limit.
*/
-static void pm_qos_work_fn(struct work_struct *work)
+s32 cpu_latency_qos_limit(void)
{
- 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);
+ return pm_qos_read_value(&cpu_latency_constraints);
}
/**
- * 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
- * @value: defines the qos request
+ * cpu_latency_qos_request_active - Check the given PM QoS request.
+ * @req: PM QoS request to check.
*
- * 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
- * handle. Caller needs to save this handle for later use in updates and
- * removal.
+ * Return: 'true' if @req has been added to the CPU latency QoS list, 'false'
+ * otherwise.
*/
-
-void pm_qos_add_request(struct pm_qos_request *req,
- int pm_qos_class, s32 value)
+bool cpu_latency_qos_request_active(struct pm_qos_request *req)
{
- if (!req) /*guard against callers passing in null */
- return;
+ return req->qos == &cpu_latency_constraints;
+}
+EXPORT_SYMBOL_GPL(cpu_latency_qos_request_active);
- if (pm_qos_request_active(req)) {
- WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n");
- 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);
+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)
+ wake_up_all_idle_cpus();
}
-EXPORT_SYMBOL_GPL(pm_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_add_request - Add new CPU latency QoS request.
+ * @req: Pointer to a preallocated handle.
+ * @value: Requested constraint value.
*
- * Updates an existing qos request for the pm_qos_class of parameters along
- * with updating the target pm_qos_class value.
+ * 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.
*
- * Attempts are made to make this code callable on hot code paths.
+ * Callers need to save the handle for later use in updates and removal of the
+ * QoS request represented by it.
*/
-void pm_qos_update_request(struct pm_qos_request *req,
- s32 new_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_update_request() called for unknown object\n");
+ if (cpu_latency_qos_request_active(req)) {
+ WARN(1, KERN_ERR "%s called for already added request\n", __func__);
return;
}
- cancel_delayed_work_sync(&req->work);
- __pm_qos_update_request(req, new_value);
+ trace_pm_qos_add_request(value);
+
+ req->qos = &cpu_latency_constraints;
+ cpu_latency_qos_apply(req, PM_QOS_ADD_REQ, value);
}
-EXPORT_SYMBOL_GPL(pm_qos_update_request);
+EXPORT_SYMBOL_GPL(cpu_latency_qos_add_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.
+ * cpu_latency_qos_update_request - Modify existing CPU latency QoS request.
+ * @req : QoS request to update.
+ * @new_value: New requested constraint value.
*
- * After timeout_us, this qos request is cancelled automatically.
+ * 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_timeout(struct pm_qos_request *req, s32 new_value,
- unsigned long timeout_us)
+void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value)
{
if (!req)
return;
- if (WARN(!pm_qos_request_active(req),
- "%s called for unknown object.", __func__))
+
+ if (!cpu_latency_qos_request_active(req)) {
+ WARN(1, KERN_ERR "%s called for unknown object\n", __func__);
return;
+ }
- cancel_delayed_work_sync(&req->work);
+ trace_pm_qos_update_request(new_value);
- 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);
+ if (new_value == req->node.prio)
+ return;
- schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us));
+ cpu_latency_qos_apply(req, PM_QOS_UPDATE_REQ, new_value);
}
+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 the pm_qos_class. 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;
}
- cancel_delayed_work_sync(&req->work);
+ trace_pm_qos_remove_request(PM_QOS_DEFAULT_VALUE);
- 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,
- 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);
-
-/**
- * pm_qos_add_notifier - sets notification entry for changes to target value
- * @pm_qos_class: identifies which qos target changes should be notified.
- * @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.
- */
-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;
-}
-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.
- * @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.
- */
-int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier)
-{
- int retval;
+EXPORT_SYMBOL_GPL(cpu_latency_qos_remove_request);
- retval = blocking_notifier_chain_unregister(
- pm_qos_array[pm_qos_class]->constraints->notifiers,
- notifier);
+/* User space interface to the CPU latency QoS via misc device. */
- return retval;
-}
-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 cpu_latency_qos_open(struct inode *inode, struct file *filp)
{
- 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);
+ struct pm_qos_request *req;
- return misc_register(&qos->pm_qos_power_miscdev);
-}
+ req = kzalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
-static int find_pm_qos_object_by_minor(int minor)
-{
- int pm_qos_class;
+ cpu_latency_qos_add_request(req, PM_QOS_DEFAULT_VALUE);
+ filp->private_data = req;
- 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;
+ return 0;
}
-static int pm_qos_power_open(struct inode *inode, struct file *filp)
+static int cpu_latency_qos_release(struct inode *inode, struct file *filp)
{
- long pm_qos_class;
-
- 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;
-
- pm_qos_add_request(req, pm_qos_class, PM_QOS_DEFAULT_VALUE);
- filp->private_data = req;
-
- return 0;
- }
- return -EPERM;
-}
+ struct pm_qos_request *req = filp->private_data;
-static int pm_qos_power_release(struct inode *inode, struct file *filp)
-{
- struct pm_qos_request *req;
+ filp->private_data = NULL;
- req = filp->private_data;
- pm_qos_remove_request(req);
+ cpu_latency_qos_remove_request(req);
kfree(req);
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)
{
- 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 || !cpu_latency_qos_request_active(req))
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_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;
- struct pm_qos_request *req;
if (count == sizeof(s32)) {
if (copy_from_user(&value, buf, sizeof(s32)))
@@ -620,36 +391,38 @@ 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);
+ cpu_latency_qos_update_request(filp->private_data, value);
return count;
}
+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 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);
+static struct miscdevice cpu_latency_qos_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "cpu_dma_latency",
+ .fops = &cpu_latency_qos_fops,
+};
- d = debugfs_create_dir("pm_qos", NULL);
+static int __init cpu_latency_qos_init(void)
+{
+ int ret;
- for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) {
- ret = register_pm_qos_misc(pm_qos_array[i], d);
- if (ret < 0) {
- pr_err("%s: %s setup failed\n",
- __func__, pm_qos_array[i]->name);
- return ret;
- }
- }
+ ret = misc_register(&cpu_latency_qos_miscdev);
+ if (ret < 0)
+ pr_err("%s: %s setup failed\n", __func__,
+ cpu_latency_qos_miscdev.name);
return ret;
}
-
-late_initcall(pm_qos_power_init);
+late_initcall(cpu_latency_qos_init);
+#endif /* CONFIG_CPU_IDLE */
/* Definitions related to the frequency QoS below. */