---

yaml
---
r: 351000
b: refs/heads/master
c: 957d128
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 89a22dadb8810983868f5bbbc5530b27bf714a60
+refs/heads/master: 957d1282bb8c07e682e142b9237cd9fcb8348a0b

trunk/Documentation/power/freezing-of-tasks.txt

@@ -223,3 +223,8 @@ since they ask the freezer to skip freezing this task, since it is anyway
 only after the entire suspend/hibernation sequence is complete.
 So, to summarize, use [un]lock_system_sleep() instead of directly using
 mutex_[un]lock(&pm_mutex). That would prevent freezing failures.
+
+V. Miscellaneous
+/sys/power/pm_freeze_timeout controls how long it will cost at most to freeze
+all user space processes or all freezable kernel threads, in unit of millisecond.
+The default value is 20000, with range of unsigned integer.

trunk/include/linux/freezer.h

@@ -12,6 +12,11 @@ extern atomic_t system_freezing_cnt;	/* nr of freezing conds in effect */
 extern bool pm_freezing;		/* PM freezing in effect */
 extern bool pm_nosig_freezing;		/* PM nosig freezing in effect */
 
+/*
+ * Timeout for stopping processes
+ */
+extern unsigned int freeze_timeout_msecs;
+
 /*
  * Check if a process has been frozen
  */

trunk/kernel/power/main.c

@@ -553,6 +553,30 @@ power_attr(pm_trace_dev_match);
 
 #endif /* CONFIG_PM_TRACE */
 
+#ifdef CONFIG_FREEZER
+static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
+				      struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%u\n", freeze_timeout_msecs);
+}
+
+static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
+				       struct kobj_attribute *attr,
+				       const char *buf, size_t n)
+{
+	unsigned long val;
+
+	if (kstrtoul(buf, 10, &val))
+		return -EINVAL;
+
+	freeze_timeout_msecs = val;
+	return n;
+}
+
+power_attr(pm_freeze_timeout);
+
+#endif	/* CONFIG_FREEZER*/
+
 static struct attribute * g[] = {
 	&state_attr.attr,
 #ifdef CONFIG_PM_TRACE
@@ -575,6 +599,9 @@ static struct attribute * g[] = {
 #ifdef CONFIG_PM_SLEEP_DEBUG
 	&pm_print_times_attr.attr,
 #endif
+#endif
+#ifdef CONFIG_FREEZER
+	&pm_freeze_timeout_attr.attr,
 #endif
 	NULL,
 };

trunk/kernel/power/process.c

@@ -21,7 +21,7 @@
 /* 
  * Timeout for stopping processes
  */
-#define TIMEOUT	(20 * HZ)
+unsigned int __read_mostly freeze_timeout_msecs = 20 * MSEC_PER_SEC;
 
 static int try_to_freeze_tasks(bool user_only)
 {
@@ -36,7 +36,7 @@ static int try_to_freeze_tasks(bool user_only)
 
 	do_gettimeofday(&start);
 
-	end_time = jiffies + TIMEOUT;
+	end_time = jiffies + msecs_to_jiffies(freeze_timeout_msecs);
 
 	if (!user_only)
 		freeze_workqueues_begin();