diff mbox

Async resume patch (was: Re: [GIT PULL] PM updates for 2.6.33)

Message ID 200912082240.42773.rjw@sisk.pl (mailing list archive)
State RFC, archived
Headers show

Commit Message

Rafael Wysocki Dec. 8, 2009, 9:40 p.m. UTC
None
diff mbox

Patch

Index: linux-2.6/include/linux/pm.h
===================================================================
--- linux-2.6.orig/include/linux/pm.h
+++ linux-2.6/include/linux/pm.h
@@ -26,6 +26,7 @@ 
 #include <linux/spinlock.h>
 #include <linux/wait.h>
 #include <linux/timer.h>
+#include <linux/rwsem.h>
 
 /*
  * Callbacks for platform drivers to implement.
@@ -412,9 +413,11 @@  struct dev_pm_info {
 	pm_message_t		power_state;
 	unsigned int		can_wakeup:1;
 	unsigned int		should_wakeup:1;
+	unsigned		async_suspend:1;
 	enum dpm_state		status;		/* Owned by the PM core */
 #ifdef CONFIG_PM_SLEEP
 	struct list_head	entry;
+	struct rw_semaphore	rwsem;
 #endif
 #ifdef CONFIG_PM_RUNTIME
 	struct timer_list	suspend_timer;
Index: linux-2.6/include/linux/device.h
===================================================================
--- linux-2.6.orig/include/linux/device.h
+++ linux-2.6/include/linux/device.h
@@ -472,6 +472,12 @@  static inline int device_is_registered(s
 	return dev->kobj.state_in_sysfs;
 }
 
+static inline void device_enable_async_suspend(struct device *dev, bool enable)
+{
+	if (dev->power.status == DPM_ON)
+		dev->power.async_suspend = enable;
+}
+
 void driver_init(void);
 
 /*
Index: linux-2.6/drivers/base/power/main.c
===================================================================
--- linux-2.6.orig/drivers/base/power/main.c
+++ linux-2.6/drivers/base/power/main.c
@@ -25,6 +25,7 @@ 
 #include <linux/resume-trace.h>
 #include <linux/rwsem.h>
 #include <linux/interrupt.h>
+#include <linux/async.h>
 
 #include "../base.h"
 #include "power.h"
@@ -42,6 +43,7 @@ 
 LIST_HEAD(dpm_list);
 
 static DEFINE_MUTEX(dpm_list_mtx);
+static pm_message_t pm_transition;
 
 /*
  * Set once the preparation of devices for a PM transition has started, reset
@@ -56,6 +58,7 @@  static bool transition_started;
 void device_pm_init(struct device *dev)
 {
 	dev->power.status = DPM_ON;
+	init_rwsem(&dev->power.rwsem);
 	pm_runtime_init(dev);
 }
 
@@ -334,25 +337,51 @@  static void pm_dev_err(struct device *de
  * The driver of @dev will not receive interrupts while this function is being
  * executed.
  */
-static int device_resume_noirq(struct device *dev, pm_message_t state)
+static int __device_resume_noirq(struct device *dev, pm_message_t state)
 {
 	int error = 0;
 
 	TRACE_DEVICE(dev);
 	TRACE_RESUME(0);
 
-	if (!dev->bus)
-		goto End;
+	down_read(&dev->parent->power.rwsem);
 
-	if (dev->bus->pm) {
+	if (dev->bus && dev->bus->pm) {
 		pm_dev_dbg(dev, state, "EARLY ");
 		error = pm_noirq_op(dev, dev->bus->pm, state);
 	}
- End:
+
+	up_read(&dev->parent->power.rwsem);
+	up_write(&dev->power.rwsem);
+
 	TRACE_RESUME(error);
 	return error;
 }
 
+static void async_resume_noirq(void *data, async_cookie_t cookie)
+{
+	struct device *dev = (struct device *)data;
+	int error;
+
+	error = __device_resume_noirq(dev, pm_transition);
+	if (error)
+		pm_dev_err(dev, pm_transition, " async EARLY", error);
+	put_device(dev);
+}
+
+static int device_resume_noirq(struct device *dev)
+{
+	down_write(&dev->power.rwsem);
+
+	if (dev->power.async_suspend && !pm_trace_is_enabled()) {
+		get_device(dev);
+		async_schedule(async_resume_noirq, dev);
+		return 0;
+	}
+
+	return __device_resume_noirq(dev, pm_transition);
+}
+
 /**
  * dpm_resume_noirq - Execute "early resume" callbacks for non-sysdev devices.
  * @state: PM transition of the system being carried out.
@@ -366,32 +395,35 @@  void dpm_resume_noirq(pm_message_t state
 
 	mutex_lock(&dpm_list_mtx);
 	transition_started = false;
+	pm_transition = state;
 	list_for_each_entry(dev, &dpm_list, power.entry)
 		if (dev->power.status > DPM_OFF) {
 			int error;
 
 			dev->power.status = DPM_OFF;
-			error = device_resume_noirq(dev, state);
+			error = device_resume_noirq(dev);
 			if (error)
 				pm_dev_err(dev, state, " early", error);
 		}
 	mutex_unlock(&dpm_list_mtx);
+	async_synchronize_full();
 	resume_device_irqs();
 }
 EXPORT_SYMBOL_GPL(dpm_resume_noirq);
 
 /**
- * device_resume - Execute "resume" callbacks for given device.
+ * __device_resume - Execute "resume" callbacks for given device.
  * @dev: Device to handle.
  * @state: PM transition of the system being carried out.
  */
-static int device_resume(struct device *dev, pm_message_t state)
+static int __device_resume(struct device *dev, pm_message_t state)
 {
 	int error = 0;
 
 	TRACE_DEVICE(dev);
 	TRACE_RESUME(0);
 
+	down_read(&dev->parent->power.rwsem);
 	down(&dev->sem);
 
 	if (dev->bus) {
@@ -426,11 +458,37 @@  static int device_resume(struct device *
 	}
  End:
 	up(&dev->sem);
+	up_read(&dev->parent->power.rwsem);
+	up_write(&dev->power.rwsem);
 
 	TRACE_RESUME(error);
 	return error;
 }
 
+static void async_resume(void *data, async_cookie_t cookie)
+{
+	struct device *dev = (struct device *)data;
+	int error;
+
+	error = __device_resume(dev, pm_transition);
+	if (error)
+		pm_dev_err(dev, pm_transition, " async", error);
+	put_device(dev);
+}
+
+static int device_resume(struct device *dev)
+{
+	down_write(&dev->power.rwsem);
+
+	if (dev->power.async_suspend && !pm_trace_is_enabled()) {
+		get_device(dev);
+		async_schedule(async_resume, dev);
+		return 0;
+	}
+
+	return __device_resume(dev, pm_transition);
+}
+
 /**
  * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
  * @state: PM transition of the system being carried out.
@@ -444,6 +502,7 @@  static void dpm_resume(pm_message_t stat
 
 	INIT_LIST_HEAD(&list);
 	mutex_lock(&dpm_list_mtx);
+	pm_transition = state;
 	while (!list_empty(&dpm_list)) {
 		struct device *dev = to_device(dpm_list.next);
 
@@ -454,7 +513,7 @@  static void dpm_resume(pm_message_t stat
 			dev->power.status = DPM_RESUMING;
 			mutex_unlock(&dpm_list_mtx);
 
-			error = device_resume(dev, state);
+			error = device_resume(dev);
 
 			mutex_lock(&dpm_list_mtx);
 			if (error)
@@ -469,6 +528,7 @@  static void dpm_resume(pm_message_t stat
 	}
 	list_splice(&list, &dpm_list);
 	mutex_unlock(&dpm_list_mtx);
+	async_synchronize_full();
 }
 
 /**
Index: linux-2.6/include/linux/resume-trace.h
===================================================================
--- linux-2.6.orig/include/linux/resume-trace.h
+++ linux-2.6/include/linux/resume-trace.h
@@ -6,6 +6,11 @@ 
 
 extern int pm_trace_enabled;
 
+static inline int pm_trace_is_enabled(void)
+{
+       return pm_trace_enabled;
+}
+
 struct device;
 extern void set_trace_device(struct device *);
 extern void generate_resume_trace(const void *tracedata, unsigned int user);
@@ -17,6 +22,8 @@  extern void generate_resume_trace(const 
 
 #else
 
+static inline int pm_trace_is_enabled(void) { return 0; }
+
 #define TRACE_DEVICE(dev) do { } while (0)
 #define TRACE_RESUME(dev) do { } while (0)