[1/2,v2] PM: Change PM subsys_data lock type into spinlock

Commit Message

Rafael Wysocki Aug. 21, 2011, 7:10 p.m. UTC

From: Rafael J. Wysocki <[e-mail]>

The lock member of struct pm_subsys_data is of type struct mutex,
which is a problem, because the suspend and resume routines
defined in drivers/base/power/clock_ops.c cannot be executed
with interrupts disabled for this reason.  Modify
struct pm_subsys_data so that its lock member is a spinlock.

Signed-off-by: Rafael J. Wysocki <[e-mail]>
---
 drivers/base/power/clock_ops.c |   35 +++++++++++++++++++++--------------
 drivers/base/power/common.c    |    2 +-
 include/linux/pm.h             |    2 +-
 3 files changed, 23 insertions(+), 16 deletions(-)

Patch

Index: linux/include/linux/pm.h
===================================================================
--- linux.orig/include/linux/pm.h
+++ linux/include/linux/pm.h
@@ -438,7 +438,7 @@  struct pm_domain_data {
 };
 
 struct pm_subsys_data {
-	struct mutex lock;
+	spinlock_t lock;
 	unsigned int refcount;
 #ifdef CONFIG_PM_CLK
 	struct list_head clock_list;
Index: linux/drivers/base/power/clock_ops.c
===================================================================
--- linux.orig/drivers/base/power/clock_ops.c
+++ linux/drivers/base/power/clock_ops.c
@@ -43,6 +43,7 @@  int pm_clk_add(struct device *dev, const
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	if (!psd)
 		return -EINVAL;
@@ -63,9 +64,9 @@  int pm_clk_add(struct device *dev, const
 		}
 	}
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 	list_add_tail(&ce->node, &psd->clock_list);
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 	return 0;
 }
 
@@ -109,11 +110,12 @@  void pm_clk_remove(struct device *dev, c
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	if (!psd)
 		return;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry(ce, &psd->clock_list, node) {
 		if (!con_id && !ce->con_id) {
@@ -127,7 +129,7 @@  void pm_clk_remove(struct device *dev, c
 		}
 	}
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 }
 
 /**
@@ -169,16 +171,17 @@  void pm_clk_destroy(struct device *dev)
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce, *c;
+	unsigned long flags;
 
 	if (!psd)
 		return;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry_safe_reverse(ce, c, &psd->clock_list, node)
 		__pm_clk_remove(ce);
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 
 	dev_pm_put_subsys_data(dev);
 }
@@ -212,13 +215,14 @@  int pm_clk_suspend(struct device *dev)
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
 	if (!psd)
 		return 0;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry_reverse(ce, &psd->clock_list, node) {
 		if (ce->status == PCE_STATUS_NONE)
@@ -230,7 +234,7 @@  int pm_clk_suspend(struct device *dev)
 		}
 	}
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 
 	return 0;
 }
@@ -243,13 +247,14 @@  int pm_clk_resume(struct device *dev)
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
 	if (!psd)
 		return 0;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry(ce, &psd->clock_list, node) {
 		if (ce->status == PCE_STATUS_NONE)
@@ -261,7 +266,7 @@  int pm_clk_resume(struct device *dev)
 		}
 	}
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 
 	return 0;
 }
@@ -336,6 +341,7 @@  int pm_clk_suspend(struct device *dev)
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
@@ -343,12 +349,12 @@  int pm_clk_suspend(struct device *dev)
 	if (!psd || !dev->driver)
 		return 0;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry_reverse(ce, &psd->clock_list, node)
 		clk_disable(ce->clk);
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 
 	return 0;
 }
@@ -361,6 +367,7 @@  int pm_clk_resume(struct device *dev)
 {
 	struct pm_subsys_data *psd = dev_to_psd(dev);
 	struct pm_clock_entry *ce;
+	unsigned long flags;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
@@ -368,12 +375,12 @@  int pm_clk_resume(struct device *dev)
 	if (!psd || !dev->driver)
 		return 0;
 
-	mutex_lock(&psd->lock);
+	spin_lock_irqsave(&psd->lock, flags);
 
 	list_for_each_entry(ce, &psd->clock_list, node)
 		clk_enable(ce->clk);
 
-	mutex_unlock(&psd->lock);
+	spin_unlock_irqrestore(&psd->lock, flags);
 
 	return 0;
 }
Index: linux/drivers/base/power/common.c
===================================================================
--- linux.orig/drivers/base/power/common.c
+++ linux/drivers/base/power/common.c
@@ -34,7 +34,7 @@  int dev_pm_get_subsys_data(struct device
 	if (dev->power.subsys_data) {
 		dev->power.subsys_data->refcount++;
 	} else {
-		mutex_init(&psd->lock);
+		spin_lock_init(&psd->lock);
 		psd->refcount = 1;
 		dev->power.subsys_data = psd;
 		pm_clk_init(dev);