> Thanks, I'll look at it over the next few days.
>
> --mgross
>
> > Here is the patch that I use with the test code. There are
> three new
> > functions:
> >
> > void *pm_qos_get(int qos, char *name);
> > int pm_qos_put(void *handle);
> > int pm_qos_update_requirement_direct(void *handle, s32
> new_value);
> >
> > In the test, I wanted to keep the existing interface intact so
> I
> > could compare them at the same time. For the formal code
> submission,
> > a different approach may work better.
Here is an alternate way of adding handles to pm_qos_params that I
was alluding to. This approach may be more preferable because it
does not bloat the API and the handles become an integral part of
pm_qos_params. In my previous patch, handles are kind of bolted onto
pm_qos_params and it needs separate calls (pm_qos_get, pm_qos_put) to
acquire and release the handle. In this patch,
pm_qos_add_requirement and pm_qos_remove_requirement automatically
take care of the handles.
--- include/linux/pm_qos_params.h.orig
+++ include/linux/pm_qos_params.h
@@ -14,9 +14,11 @@
#define PM_QOS_NUM_CLASSES 4
#define PM_QOS_DEFAULT_VALUE -1
-int pm_qos_add_requirement(int qos, char *name, s32 value);
-int pm_qos_update_requirement(int qos, char *name, s32 new_value);
-void pm_qos_remove_requirement(int qos, char *name);
+struct requirement_list;
+
+struct requirement_list *pm_qos_add_requirement(int qos, char *name,
s32 value);
+int pm_qos_update_requirement(struct requirement_list *qos, s32
new_value);
+void pm_qos_remove_requirement(struct requirement_list *qos);
int pm_qos_requirement(int qos);
--- kernel/pm_qos_params.c.orig
+++ kernel/pm_qos_params.c
@@ -49,6 +49,7 @@
*/
struct requirement_list {
struct list_head list;
+ int pm_qos_class;
union {
s32 value;
s32 usec;
@@ -207,13 +208,16 @@ EXPORT_SYMBOL_GPL(pm_qos_requirement);
* performance characteristics. It recomputes the aggregate QoS
expectations
* for the pm_qos_class of parameters.
*/
-int pm_qos_add_requirement(int pm_qos_class, char *name, s32 value)
+struct requirement_list *pm_qos_add_requirement(int pm_qos_class,
char *name,
+ s32 value)
{
struct requirement_list *dep;
unsigned long flags;
dep = kzalloc(sizeof(struct requirement_list), GFP_KERNEL);
if (dep) {
+ dep->pm_qos_class = pm_qos_class;
+
if (value == PM_QOS_DEFAULT_VALUE)
dep->value =
pm_qos_array[pm_qos_class]->default_value;
else
@@ -228,48 +232,37 @@ int pm_qos_add_requirement(int pm_qos_class,
char *name, s32 value)
spin_unlock_irqrestore(&pm_qos_lock, flags);
update_target(pm_qos_class);
- return 0;
+ return dep;
}
cleanup:
kfree(dep);
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
}
EXPORT_SYMBOL_GPL(pm_qos_add_requirement);
/**
* pm_qos_update_requirement - modifies an existing qos request
- * @pm_qos_class: identifies which list of qos request to us
- * @name: identifies the request
+ * @qos: identifies the qos request to us
* @value: defines the qos request
*
- * Updates an existing qos requirement for the pm_qos_class of
parameters along
+ * Updates an existing qos requirement along
* with updating the target pm_qos_class value.
- *
- * If the named request isn't in the list then no change is made.
*/
-int pm_qos_update_requirement(int pm_qos_class, char *name, s32
new_value)
+int pm_qos_update_requirement(struct requirement_list *qos, s32
new_value)
{
unsigned long flags;
- struct requirement_list *node;
int pending_update = 0;
spin_lock_irqsave(&pm_qos_lock, flags);
- list_for_each_entry(node,
- &pm_qos_array[pm_qos_class]->requirements.list, list)
{
- if (strcmp(node->name, name) == 0) {
- if (new_value == PM_QOS_DEFAULT_VALUE)
- node->value =
-
pm_qos_array[pm_qos_class]->default_value;
- else
- node->value = new_value;
- pending_update = 1;
- break;
- }
- }
+ if (new_value == PM_QOS_DEFAULT_VALUE)
+ qos->value =
pm_qos_array[qos->pm_qos_class]->default_value;
+ else
+ qos->value = new_value;
+ pending_update = 1;
spin_unlock_irqrestore(&pm_qos_lock, flags);
if (pending_update)
- update_target(pm_qos_class);
+ update_target(qos->pm_qos_class);
return 0;
}
@@ -277,32 +270,26 @@ EXPORT_SYMBOL_GPL(pm_qos_update_requirement);
/**
* pm_qos_remove_requirement - modifies an existing qos request
- * @pm_qos_class: identifies which list of qos request to us
+ * @qos: identifies the qos request to us
* @name: identifies the request
*
- * Will remove named qos request from pm_qos_class list of
parameters and
+ * Will remove qos request from pm_qos_class list and
* recompute the current target value for the pm_qos_class.
*/
-void pm_qos_remove_requirement(int pm_qos_class, char *name)
+void pm_qos_remove_requirement(struct requirement_list *qos)
{
unsigned long flags;
- struct requirement_list *node;
int pending_update = 0;
spin_lock_irqsave(&pm_qos_lock, flags);
- list_for_each_entry(node,
- &pm_qos_array[pm_qos_class]->requirements.list, list)
{
- if (strcmp(node->name, name) == 0) {
- kfree(node->name);
- list_del(&node->list);
- kfree(node);
- pending_update = 1;
- break;
- }
- }
+ list_del(&qos->list);
+ pending_update = 1;
spin_unlock_irqrestore(&pm_qos_lock, flags);
if (pending_update)
- update_target(pm_qos_class);
+ update_target(qos->pm_qos_class);
+
+ kfree(qos->name);
+ kfree(qos);
}
EXPORT_SYMBOL_GPL(pm_qos_remove_requirement);
@@ -345,37 +332,42 @@ int pm_qos_remove_notifier(int pm_qos_class,
struct notifier_block *notifier)
EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
#define PID_NAME_LEN sizeof("process_1234567890")
-static char name[PID_NAME_LEN];
static int pm_qos_power_open(struct inode *inode, struct file *filp)
{
int ret;
long pm_qos_class;
+ char name[PID_NAME_LEN];
+ struct requirement_list *qos;
lock_kernel();
pm_qos_class = find_pm_qos_object_by_minor(iminor(inode));
- if (pm_qos_class >= 0) {
- filp->private_data = (void *)pm_qos_class;
- sprintf(name, "process_%d", current->pid);
- ret = pm_qos_add_requirement(pm_qos_class, name,
- PM_QOS_DEFAULT_VALUE);
- if (ret >= 0) {
- unlock_kernel();
- return 0;
- }
+ if (pm_qos_class < 0) {
+ ret = -EPERM;
+ goto power_open_exit;
}
- unlock_kernel();
- return -EPERM;
+ sprintf(name, "process_%d", current->pid);
+ qos = pm_qos_add_requirement(pm_qos_class, name,
PM_QOS_DEFAULT_VALUE);
+ if (IS_ERR(qos)) {
+ ret = PTR_ERR(qos);
+ goto power_open_exit;
+ }
+
+ filp->private_data = qos;
+ ret = 0;
+
+power_open_exit:
+ unlock_kernel();
+ return ret;
}
static int pm_qos_power_release(struct inode *inode, struct file
*filp)
{
- int pm_qos_class;
+ struct requirement_list *qos;
- pm_qos_class = (long)filp->private_data;
- sprintf(name, "process_%d", current->pid);
- pm_qos_remove_requirement(pm_qos_class, name);
+ qos = (struct requirement_list *)filp->private_data;
+ pm_qos_remove_requirement(qos);
return 0;
}
@@ -384,15 +376,15 @@ static ssize_t pm_qos_power_write(struct file
*filp, const char __user *buf,
size_t count, loff_t *f_pos)
{
s32 value;
- int pm_qos_class;
+ struct requirement_list *qos;
- pm_qos_class = (long)filp->private_data;
if (count != sizeof(s32))
return -EINVAL;
if (copy_from_user(&value, buf, sizeof(s32)))
return -EFAULT;
- sprintf(name, "process_%d", current->pid);
- pm_qos_update_requirement(pm_qos_class, name, value);
+
+ qos = (struct requirement_list *)filp->private_data;
+ pm_qos_update_requirement(qos, value);
return sizeof(s32);
}
~Ai
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