linux-kernel - [PATCH v1 2/5] PM: sleep: Rearrange dpm_async

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Message-ID: <8494650.T7Z3S40VBb@rjwysocki.net>
Date: Tue, 25 Feb 2025 17:39:40 +0100
From: "Rafael J. Wysocki" <rjw@...ysocki.net>
To: Linux PM <linux-pm@...r.kernel.org>
Cc: LKML <linux-kernel@...r.kernel.org>,
 Alan Stern <stern@...land.harvard.edu>, Ulf Hansson <ulf.hansson@...aro.org>,
 Johan Hovold <johan@...nel.org>,
 Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>,
 Saravana Kannan <saravanak@...gle.com>
Subject:
 [PATCH v1 2/5] PM: sleep: Rearrange dpm_async_fn() and async state clearing

From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

In preparation for subsequent changes, move the power.completion
reinitialization along with clearing power.work_in_progress into a
separate function called dpm_clear_async_state() and rearrange
dpm_async_fn() to get rid of unnecessary indentation.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/base/power/main.c |   44 ++++++++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 14 deletions(-)

--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -599,27 +599,34 @@
 
 static bool dpm_async_fn(struct device *dev, async_func_t func)
 {
-	reinit_completion(&dev->power.completion);
+	if (!is_async(dev))
+		return false;
 
-	if (is_async(dev)) {
-		dev->power.work_in_progress = true;
+	dev->power.work_in_progress = true;
 
-		get_device(dev);
+	get_device(dev);
 
-		if (async_schedule_dev_nocall(func, dev))
-			return true;
+	if (async_schedule_dev_nocall(func, dev))
+		return true;
+
+	put_device(dev);
 
-		put_device(dev);
-	}
 	/*
-	 * Because async_schedule_dev_nocall() above has returned false or it
-	 * has not been called at all, func() is not running and it is safe to
-	 * update the work_in_progress flag without extra synchronization.
+	 * async_schedule_dev_nocall() above has returned false, so func() is
+	 * not running and it is safe to update power.work_in_progress without
+	 * extra synchronization.
 	 */
 	dev->power.work_in_progress = false;
+
 	return false;
 }
 
+static void dpm_clear_async_state(struct device *dev)
+{
+	reinit_completion(&dev->power.completion);
+	dev->power.work_in_progress = false;
+}
+
 /**
  * device_resume_noirq - Execute a "noirq resume" callback for given device.
  * @dev: Device to handle.
@@ -729,8 +736,10 @@
 	 * Trigger the resume of "async" devices upfront so they don't have to
 	 * wait for the "non-async" ones they don't depend on.
 	 */
-	list_for_each_entry(dev, &dpm_noirq_list, power.entry)
+	list_for_each_entry(dev, &dpm_noirq_list, power.entry) {
+		dpm_clear_async_state(dev);
 		dpm_async_fn(dev, async_resume_noirq);
+	}
 
 	while (!list_empty(&dpm_noirq_list)) {
 		dev = to_device(dpm_noirq_list.next);
@@ -869,8 +878,10 @@
 	 * Trigger the resume of "async" devices upfront so they don't have to
 	 * wait for the "non-async" ones they don't depend on.
 	 */
-	list_for_each_entry(dev, &dpm_late_early_list, power.entry)
+	list_for_each_entry(dev, &dpm_late_early_list, power.entry) {
+		dpm_clear_async_state(dev);
 		dpm_async_fn(dev, async_resume_early);
+	}
 
 	while (!list_empty(&dpm_late_early_list)) {
 		dev = to_device(dpm_late_early_list.next);
@@ -1035,8 +1046,10 @@
 	 * Trigger the resume of "async" devices upfront so they don't have to
 	 * wait for the "non-async" ones they don't depend on.
 	 */
-	list_for_each_entry(dev, &dpm_suspended_list, power.entry)
+	list_for_each_entry(dev, &dpm_suspended_list, power.entry) {
+		dpm_clear_async_state(dev);
 		dpm_async_fn(dev, async_resume);
+	}
 
 	while (!list_empty(&dpm_suspended_list)) {
 		dev = to_device(dpm_suspended_list.next);
@@ -1314,6 +1327,7 @@
 
 		list_move(&dev->power.entry, &dpm_noirq_list);
 
+		dpm_clear_async_state(dev);
 		if (dpm_async_fn(dev, async_suspend_noirq))
 			continue;
 
@@ -1491,6 +1505,7 @@
 
 		list_move(&dev->power.entry, &dpm_late_early_list);
 
+		dpm_clear_async_state(dev);
 		if (dpm_async_fn(dev, async_suspend_late))
 			continue;
 
@@ -1758,6 +1773,7 @@
 
 		list_move(&dev->power.entry, &dpm_suspended_list);
 
+		dpm_clear_async_state(dev);
 		if (dpm_async_fn(dev, async_suspend))
 			continue;