diff options
| -rw-r--r-- | Documentation/power/freezing-of-tasks.txt | 5 | ||||
| -rw-r--r-- | include/linux/freezer.h | 5 | ||||
| -rw-r--r-- | kernel/power/main.c | 27 | ||||
| -rw-r--r-- | kernel/power/process.c | 4 |
4 files changed, 39 insertions, 2 deletions
diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index 6ec291ea1c78..85894d83b352 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/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. diff --git a/include/linux/freezer.h b/include/linux/freezer.h index e4238ceaa4d6..e70df40d84f6 100644 --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -13,6 +13,11 @@ 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 */ static inline bool frozen(struct task_struct *p) diff --git a/kernel/power/main.c b/kernel/power/main.c index b1c26a92ca9f..d77663bfedeb 100644 --- a/kernel/power/main.c +++ b/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 @@ -576,6 +600,9 @@ static struct attribute * g[] = { &pm_print_times_attr.attr, #endif #endif +#ifdef CONFIG_FREEZER + &pm_freeze_timeout_attr.attr, +#endif NULL, }; diff --git a/kernel/power/process.c b/kernel/power/process.c index d5a258b60c6f..98088e0e71e8 100644 --- a/kernel/power/process.c +++ b/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(); |