diff options
Diffstat (limited to 'kernel/power/main.c')
-rw-r--r-- | kernel/power/main.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/kernel/power/main.c b/kernel/power/main.c index 3113ec2f1db4..f6425ae3e8b0 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -21,6 +21,33 @@ #include "power.h" #ifdef CONFIG_PM_SLEEP +/* + * The following functions are used by the suspend/hibernate code to temporarily + * change gfp_allowed_mask in order to avoid using I/O during memory allocations + * while devices are suspended. To avoid races with the suspend/hibernate code, + * they should always be called with system_transition_mutex held + * (gfp_allowed_mask also should only be modified with system_transition_mutex + * held, unless the suspend/hibernate code is guaranteed not to run in parallel + * with that modification). + */ +static gfp_t saved_gfp_mask; + +void pm_restore_gfp_mask(void) +{ + WARN_ON(!mutex_is_locked(&system_transition_mutex)); + if (saved_gfp_mask) { + gfp_allowed_mask = saved_gfp_mask; + saved_gfp_mask = 0; + } +} + +void pm_restrict_gfp_mask(void) +{ + WARN_ON(!mutex_is_locked(&system_transition_mutex)); + WARN_ON(saved_gfp_mask); + saved_gfp_mask = gfp_allowed_mask; + gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS); +} unsigned int lock_system_sleep(void) { @@ -556,6 +583,12 @@ power_attr_ro(pm_wakeup_irq); bool pm_debug_messages_on __read_mostly; +bool pm_debug_messages_should_print(void) +{ + return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON; +} +EXPORT_SYMBOL_GPL(pm_debug_messages_should_print); + static ssize_t pm_debug_messages_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { |