From: Jean Pihet <j-pihet@xxxxxx>
The devices wake-up latency constraints class of PM QoS is
storing the constraints list using the device pm_info struct.
This patch adds the init and de-init of the per-device constraints
list in order to support the dynamic insertion and removal
of the devices in the system.
Signed-off-by: Jean Pihet <j-pihet@xxxxxx>
---
drivers/base/power/main.c | 8 +++--
include/linux/pm.h | 1 +
include/linux/pm_qos_params.h | 2 +
kernel/pm_qos_params.c | 70 ++++++++++++++++++++++++++++++++--------
4 files changed, 64 insertions(+), 17 deletions(-)
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index b1fd96b..51f5526 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -27,6 +27,7 @@
#include <linux/sched.h>
#include <linux/async.h>
#include <linux/suspend.h>
+#include <linux/pm_qos_params.h>
#include "../base.h"
#include "power.h"
@@ -96,8 +97,8 @@ void device_pm_add(struct device *dev)
dev_name(dev->parent));
list_add_tail(&dev->power.entry, &dpm_list);
mutex_unlock(&dpm_list_mtx);
- /* ToDo: call PM QoS to init the per-device wakeup latency constraints */
- plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
+ /* Call PM QoS to init the per-device wakeup latency constraints */
+ pm_qos_dev_wakeup_lat_init(dev);
}
/**
@@ -108,7 +109,8 @@ void device_pm_remove(struct device *dev)
{
pr_debug("PM: Removing info for %s:%s\n",
dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
- /* ToDo: call PM QoS to de-init the per-device wakeup latency constraints */
+ /* Call PM QoS to de-init the per-device wakeup latency constraints */
+ pm_qos_dev_wakeup_lat_deinit(dev);
complete_all(&dev->power.completion);
mutex_lock(&dpm_list_mtx);
list_del_init(&dev->power.entry);
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 35fe682..d9b6092 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -464,6 +464,7 @@ struct dev_pm_info {
void *subsys_data; /* Owned by the subsystem. */
#endif
struct plist_head wakeup_lat_plist_head;
+ int wakeup_lat_init;
};
extern void update_pm_runtime_accounting(struct device *dev);
diff --git a/include/linux/pm_qos_params.h b/include/linux/pm_qos_params.h
index e6e16cb..5b6707a 100644
--- a/include/linux/pm_qos_params.h
+++ b/include/linux/pm_qos_params.h
@@ -45,4 +45,6 @@ int pm_qos_add_notifier(int class, struct notifier_block *notifier);
int pm_qos_remove_notifier(int class, struct notifier_block *notifier);
int pm_qos_request_active(struct pm_qos_request_list *req);
+void pm_qos_dev_wakeup_lat_init(struct device *dev);
+void pm_qos_dev_wakeup_lat_deinit(struct device *dev);
#endif
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index d61c8e5..6f25ccb 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -275,11 +275,21 @@ void pm_qos_add_request(struct pm_qos_request_list *pm_qos_req,
struct pm_qos_object *o = pm_qos_array[pm_qos_params->class];
int new_value;
- if ((pm_qos_params->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
- (pm_qos_request_active(pm_qos_req))) {
- WARN(1, KERN_ERR "pm_qos_add_request() called for already "
- "added request\n");
- return;
+ if (pm_qos_params->class == PM_QOS_DEV_WAKEUP_LATENCY) {
+ if (!pm_qos_params->dev) {
+ WARN(1, KERN_ERR "pm_qos_add_request() called for "
+ "invalid device\n");
+ return;
+ }
+ /* Silently return if the device is being released */
+ if (!pm_qos_params->dev->power.wakeup_lat_init)
+ return;
+ } else {
+ if (pm_qos_request_active(pm_qos_req)) {
+ WARN(1, KERN_ERR "pm_qos_add_request() called for "
+ "already added request\n");
+ return;
+ }
}
if (pm_qos_params->value == PM_QOS_DEFAULT_VALUE)
@@ -312,11 +322,16 @@ void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req,
if (!pm_qos_req) /*guard against callers passing in null */
return;
- if ((pm_qos_req->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
- (!pm_qos_request_active(pm_qos_req))) {
- WARN(1, KERN_ERR "pm_qos_update_request() called for unknown "
- "object\n");
- return;
+ if (pm_qos_req->class == PM_QOS_DEV_WAKEUP_LATENCY) {
+ /* Silently return if the device is being released */
+ if (!pm_qos_req->dev->power.wakeup_lat_init)
+ return;
+ } else {
+ if (!pm_qos_request_active(pm_qos_req)) {
+ WARN(1, KERN_ERR "pm_qos_update_request() called "
+ "for unknown object\n");
+ return;
+ }
}
if (new_value == PM_QOS_DEFAULT_VALUE)
@@ -343,11 +358,16 @@ void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req)
return;
/* silent return to keep pcm code cleaner */
- if ((pm_qos_req->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
- (!pm_qos_request_active(pm_qos_req))) {
- WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown "
- "object\n");
+ if (pm_qos_req->class == PM_QOS_DEV_WAKEUP_LATENCY) {
+ /* Silently return if the device is being released */
+ if (!pm_qos_req->dev->power.wakeup_lat_init)
+ return;
+ } else {
+ if (!pm_qos_request_active(pm_qos_req)) {
+ WARN(1, KERN_ERR "pm_qos_remove_request() called "
+ "for unknown object\n");
return;
+ }
}
update_target(pm_qos_req, 1, PM_QOS_DEFAULT_VALUE);
@@ -393,6 +413,28 @@ int pm_qos_remove_notifier(int class, struct notifier_block *notifier)
}
EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
+/* Called from the device PM subsystem at device init */
+void pm_qos_dev_wakeup_lat_init(struct device *dev)
+{
+ plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
+ dev->power.wakeup_lat_init = 1;
+}
+
+/* Called from the device PM subsystem at device release */
+void pm_qos_dev_wakeup_lat_deinit(struct device *dev)
+{
+ struct pm_qos_request_list *req, *tmp;
+
+ dev->power.wakeup_lat_init = 0;
+
+ /* Flush the constraints list for the device */
+ plist_for_each_entry_safe(req, tmp,
+ &dev->power.wakeup_lat_plist_head,
+ list)
+ update_target(req, 1, PM_QOS_DEFAULT_VALUE);
+ plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
+}
+
static int pm_qos_power_open(struct inode *inode, struct file *filp)
{
struct pm_qos_parameters pm_qos_params;
--
1.7.4.1
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