#include <net/compat.h>
-/* All things not in 2.6.22, 2.6.23 and 2.6.24 */
+/* This is the backport of pm-qos params for kernels <= 2.6.25 */
#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25))
+/*
+ * This module exposes the interface to kernel space for specifying
+ * QoS dependencies. It provides infrastructure for registration of:
+ *
+ * Dependents on a QoS value : register requirements
+ * Watchers of QoS value : get notified when target QoS value changes
+ *
+ * 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.
+ *
+ * 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)
+ *
+ * There are lists of pm_qos_objects each one wrapping requirements, notifiers
+ *
+ * User mode requirements 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
+ * requirement is removed and a new qos target is computed. This way when the
+ * requirement 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>
+ */
+
+#include <linux/pm_qos_params.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/device.h>
#include <linux/miscdevice.h>
+#include <linux/string.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+
+#include <linux/uaccess.h>
/*
- * locking rule: all changes to target_value or requirements or notifiers lists
+ * locking rule: all changes to requirements or notifiers lists
* 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 miscdevice pm_qos_power_miscdev;
char *name;
s32 default_value;
- s32 target_value;
+ atomic_t target_value;
s32 (*comparitor)(s32, s32);
};
.notifiers = &cpu_dma_lat_notifier,
.name = "cpu_dma_latency",
.default_value = 2000 * USEC_PER_SEC,
- .target_value = 2000 * USEC_PER_SEC,
+ .target_value = ATOMIC_INIT(2000 * USEC_PER_SEC),
.comparitor = min_compare
};
.notifiers = &network_lat_notifier,
.name = "network_latency",
.default_value = 2000 * USEC_PER_SEC,
- .target_value = 2000 * USEC_PER_SEC,
+ .target_value = ATOMIC_INIT(2000 * USEC_PER_SEC),
.comparitor = min_compare
};
.notifiers = &network_throughput_notifier,
.name = "network_throughput",
.default_value = 0,
- .target_value = 0,
+ .target_value = ATOMIC_INIT(0),
.comparitor = max_compare
};
.notifiers = &system_bus_freq_notifier,
.name = "system_bus_freq",
.default_value = 0,
- .target_value = 0,
+ .target_value = ATOMIC_INIT(0),
.comparitor = max_compare
};
-static struct pm_qos_object *pm_qos_array[] = {
+static struct pm_qos_object *pm_qos_array[PM_QOS_NUM_CLASSES] = {
[PM_QOS_RESERVED] = &null_pm_qos,
[PM_QOS_CPU_DMA_LATENCY] = &cpu_dma_pm_qos,
[PM_QOS_NETWORK_LATENCY] = &network_lat_pm_qos,
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,
- .open = pm_qos_power_open,
- .release = pm_qos_power_release,
+ .write = pm_qos_power_write,
+ .open = pm_qos_power_open,
+ .release = pm_qos_power_release,
};
/* static helper functions */
return min(v1, v2);
}
+
static void update_target(int target)
{
s32 extreme_value;
extreme_value = pm_qos_array[target]->comparitor(
extreme_value, node->value);
}
- if (pm_qos_array[target]->target_value != extreme_value) {
+ if (atomic_read(&pm_qos_array[target]->target_value) != extreme_value) {
call_notifier = 1;
- pm_qos_array[target]->target_value = extreme_value;
+ atomic_set(&pm_qos_array[target]->target_value, extreme_value);
pr_debug(KERN_ERR "new target for qos %d is %d\n", target,
- pm_qos_array[target]->target_value);
+ atomic_read(&pm_qos_array[target]->target_value));
}
spin_unlock_irqrestore(&pm_qos_lock, flags);
*/
int pm_qos_requirement(int pm_qos_class)
{
- int ret_val;
- unsigned long flags;
-
- spin_lock_irqsave(&pm_qos_lock, flags);
- ret_val = pm_qos_array[pm_qos_class]->target_value;
- spin_unlock_irqrestore(&pm_qos_lock, flags);
-
- return ret_val;
+ return atomic_read(&pm_qos_array[pm_qos_class]->target_value);
}
EXPORT_SYMBOL_GPL(pm_qos_requirement);
* @value: defines the qos request
*
* This function inserts a new entry in the pm_qos_class list of requested qos
- * performance charactoistics. It recomputes the agregate QoS expectations for
- * the pm_qos_class of parrameters.
+ * 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)
{
* @name: identifies the request
* @value: defines the qos request
*
- * Updates an existing qos requierement for the pm_qos_class of parameters along
+ * Updates an existing qos requirement for the pm_qos_class of parameters along
* with updating the target pm_qos_class value.
*
- * If the named request isn't in the lest then no change is made.
+ * 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)
{
* @pm_qos_class: identifies which list of qos request to us
* @name: identifies the request
*
- * Will remove named qos request from pm_qos_class list of parrameters and
+ * Will remove named qos request from pm_qos_class list of parameters and
* recompute the current target value for the pm_qos_class.
*/
void pm_qos_remove_requirement(int pm_qos_class, char *name)
* @notifier: notifier block managed by caller.
*
* will register the notifier into a notification chain that gets called
- * uppon changes to the pm_qos_class target value.
+ * upon changes to the pm_qos_class target value.
*/
- int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
+int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
{
int retval;
* @notifier: notifier block to be removed.
*
* will remove the notifier from the notification chain that gets called
- * uppon changes to the pm_qos_class target value.
+ * upon changes to the pm_qos_class target value.
*/
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];
+#define PID_NAME_LEN 32
static int pm_qos_power_open(struct inode *inode, struct file *filp)
{
int ret;
long pm_qos_class;
+ char name[PID_NAME_LEN];
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);
+ snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
ret = pm_qos_add_requirement(pm_qos_class, name,
PM_QOS_DEFAULT_VALUE);
if (ret >= 0)
return 0;
}
-
return -EPERM;
}
static int pm_qos_power_release(struct inode *inode, struct file *filp)
{
int pm_qos_class;
+ char name[PID_NAME_LEN];
pm_qos_class = (long)filp->private_data;
- sprintf(name, "process_%d", current->pid);
+ snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
pm_qos_remove_requirement(pm_qos_class, name);
return 0;
{
s32 value;
int pm_qos_class;
+ char name[PID_NAME_LEN];
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);
+ snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
pm_qos_update_requirement(pm_qos_class, name, value);
return sizeof(s32);
}
+
/*
* This initializes pm-qos for older kernels.
*/
return ret;
}
ret = register_pm_qos_misc(&system_bus_freq_pm_qos);
- if (ret < 0) {
+ if (ret < 0)
printk(KERN_ERR
- "pm_qos_param: network_throughput setup failed\n");
- return ret;
- }
+ "pm_qos_param: system_bus_freq setup failed\n");
return ret;
}
-
#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25) */
projects / openwrt / staging / blogic.git / commitdiff