Commit 5950e5d5 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

freezer: Have {,un}lock_system_sleep() save/restore flags 



Rafael explained that the reason for having both PF_NOFREEZE and
PF_FREEZER_SKIP is that {,un}lock_system_sleep() is callable from
kthread context that has previously called set_freezable().

In preparation of merging the flags, have {,un}lock_system_slee() save
and restore current->flags.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220822114648.725003428@infradead.org
parent 0b9d46fc

drivers/acpi/x86/s2idle.c

+8 −4
Original line number Diff line number Diff line
@@ -541,12 +541,14 @@ void acpi_s2idle_setup(void) 


int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg)

{

	unsigned int sleep_flags;



	if (!lps0_device_handle || sleep_no_lps0)

		return -ENODEV;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();

	list_add(&arg->list_node, &lps0_s2idle_devops_head);

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);



	return 0;

}
@@ -554,12 +556,14 @@ EXPORT_SYMBOL_GPL(acpi_register_lps0_dev); 


void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg)

{

	unsigned int sleep_flags;



	if (!lps0_device_handle || sleep_no_lps0)

		return;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();

	list_del(&arg->list_node);

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);

}

EXPORT_SYMBOL_GPL(acpi_unregister_lps0_dev);

drivers/scsi/scsi_transport_spi.c

+4 −3
Original line number Diff line number Diff line
@@ -998,8 +998,9 @@ void 
spi_dv_device(struct scsi_device *sdev)

{

	struct scsi_target *starget = sdev->sdev_target;

	u8 *buffer;

	const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;

	unsigned int sleep_flags;

	u8 *buffer;



	/*

	 * Because this function and the power management code both call
@@ -1007,7 +1008,7 @@ spi_dv_device(struct scsi_device *sdev) 
	 * while suspend or resume is in progress. Hence the

	 * lock/unlock_system_sleep() calls.

	 */

	lock_system_sleep();

	sleep_flags = lock_system_sleep();



	if (scsi_autopm_get_device(sdev))

		goto unlock_system_sleep;
@@ -1058,7 +1059,7 @@ spi_dv_device(struct scsi_device *sdev) 
	scsi_autopm_put_device(sdev);



unlock_system_sleep:

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);

}

EXPORT_SYMBOL(spi_dv_device);

include/linux/suspend.h

+4 −4
Original line number Diff line number Diff line
@@ -510,8 +510,8 @@ extern bool pm_save_wakeup_count(unsigned int count); 
extern void pm_wakep_autosleep_enabled(bool set);

extern void pm_print_active_wakeup_sources(void);



extern void lock_system_sleep(void);

extern void unlock_system_sleep(void);

extern unsigned int lock_system_sleep(void);

extern void unlock_system_sleep(unsigned int);



#else /* !CONFIG_PM_SLEEP */
@@ -534,8 +534,8 @@ static inline void pm_system_wakeup(void) {} 
static inline void pm_wakeup_clear(bool reset) {}

static inline void pm_system_irq_wakeup(unsigned int irq_number) {}



static inline void lock_system_sleep(void) {}

static inline void unlock_system_sleep(void) {}

static inline unsigned int lock_system_sleep(void) { return 0; }

static inline void unlock_system_sleep(unsigned int flags) {}



#endif /* !CONFIG_PM_SLEEP */

kernel/power/hibernate.c

+22 −13
Original line number Diff line number Diff line
@@ -92,20 +92,24 @@ bool hibernation_available(void) 
 */

void hibernation_set_ops(const struct platform_hibernation_ops *ops)

{

	unsigned int sleep_flags;



	if (ops && !(ops->begin && ops->end &&  ops->pre_snapshot

	    && ops->prepare && ops->finish && ops->enter && ops->pre_restore

	    && ops->restore_cleanup && ops->leave)) {

		WARN_ON(1);

		return;

	}

	lock_system_sleep();



	sleep_flags = lock_system_sleep();



	hibernation_ops = ops;

	if (ops)

		hibernation_mode = HIBERNATION_PLATFORM;

	else if (hibernation_mode == HIBERNATION_PLATFORM)

		hibernation_mode = HIBERNATION_SHUTDOWN;



	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);

}

EXPORT_SYMBOL_GPL(hibernation_set_ops);
@@ -713,6 +717,7 @@ static int load_image_and_restore(void) 
int hibernate(void)

{

	bool snapshot_test = false;

	unsigned int sleep_flags;

	int error;



	if (!hibernation_available()) {
@@ -720,7 +725,7 @@ int hibernate(void) 
		return -EPERM;

	}



	lock_system_sleep();

	sleep_flags = lock_system_sleep();

	/* The snapshot device should not be opened while we're running */

	if (!hibernate_acquire()) {

		error = -EBUSY;
@@ -794,7 +799,7 @@ int hibernate(void) 
	pm_restore_console();

	hibernate_release();

 Unlock:

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);

	pr_info("hibernation exit\n");



	return error;
@@ -809,9 +814,10 @@ int hibernate(void) 
 */

int hibernate_quiet_exec(int (*func)(void *data), void *data)

{

	unsigned int sleep_flags;

	int error;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();



	if (!hibernate_acquire()) {

		error = -EBUSY;
@@ -891,7 +897,7 @@ int hibernate_quiet_exec(int (*func)(void *data), void *data) 
	hibernate_release();



unlock:

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);



	return error;

}
@@ -1100,11 +1106,12 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, 
static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,

			  const char *buf, size_t n)

{

	int mode = HIBERNATION_INVALID;

	unsigned int sleep_flags;

	int error = 0;

	int i;

	int len;

	char *p;

	int mode = HIBERNATION_INVALID;

	int i;



	if (!hibernation_available())

		return -EPERM;
@@ -1112,7 +1119,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, 
	p = memchr(buf, '\n', n);

	len = p ? p - buf : n;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();

	for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {

		if (len == strlen(hibernation_modes[i])

		    && !strncmp(buf, hibernation_modes[i], len)) {
@@ -1142,7 +1149,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, 
	if (!error)

		pm_pr_dbg("Hibernation mode set to '%s'\n",

			       hibernation_modes[mode]);

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);

	return error ? error : n;

}
@@ -1158,9 +1165,10 @@ static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr, 
static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,

			    const char *buf, size_t n)

{

	dev_t res;

	unsigned int sleep_flags;

	int len = n;

	char *name;

	dev_t res;



	if (len && buf[len-1] == '\n')

		len--;
@@ -1173,9 +1181,10 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, 
	if (!res)

		return -EINVAL;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();

	swsusp_resume_device = res;

	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);



	pm_pr_dbg("Configured hibernation resume from disk to %u\n",

		  swsusp_resume_device);

	noresume = 0;

kernel/power/main.c

+10 −6
Original line number Diff line number Diff line
@@ -21,14 +21,16 @@ 


#ifdef CONFIG_PM_SLEEP



void lock_system_sleep(void)

unsigned int lock_system_sleep(void)

{

	unsigned int flags = current->flags;

	current->flags |= PF_FREEZER_SKIP;

	mutex_lock(&system_transition_mutex);

	return flags;

}

EXPORT_SYMBOL_GPL(lock_system_sleep);



void unlock_system_sleep(void)

void unlock_system_sleep(unsigned int flags)

{

	/*

	 * Don't use freezer_count() because we don't want the call to
@@ -46,6 +48,7 @@ void unlock_system_sleep(void) 
	 * Which means, if we use try_to_freeze() here, it would make them

	 * enter the refrigerator, thus causing hibernation to lockup.

	 */

	if (!(flags & PF_FREEZER_SKIP))

		current->flags &= ~PF_FREEZER_SKIP;

	mutex_unlock(&system_transition_mutex);

}
@@ -263,16 +266,17 @@ static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, 
static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,

				const char *buf, size_t n)

{

	unsigned int sleep_flags;

	const char * const *s;

	int error = -EINVAL;

	int level;

	char *p;

	int len;

	int error = -EINVAL;



	p = memchr(buf, '\n', n);

	len = p ? p - buf : n;



	lock_system_sleep();

	sleep_flags = lock_system_sleep();



	level = TEST_FIRST;

	for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
@@ -282,7 +286,7 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, 
			break;

		}



	unlock_system_sleep();

	unlock_system_sleep(sleep_flags);



	return error ? error : n;

}