Merge branches 'pm-core', 'pm-domains', 'pm-sleep', 'acpi-pm' and 'pm-cpuidle'

Merge changes in the PM core, system-wide PM infrastructure, generic
power domains (genpd) framework, ACPI PM infrastructure and cpuidle
for 4.19.

* pm-core:
  driver core: Add flag to autoremove device link on supplier unbind
  driver core: Rename flag AUTOREMOVE to AUTOREMOVE_CONSUMER

* pm-domains:
  PM / Domains: Introduce dev_pm_domain_attach_by_name()
  PM / Domains: Introduce option to attach a device by name to genpd
  PM / Domains: dt: Add a power-domain-names property

* pm-sleep:
  PM / reboot: Eliminate race between reboot and suspend
  PM / hibernate: Mark expected switch fall-through
  x86/power/hibernate_64: Remove VLA usage
  PM / hibernate: cast PAGE_SIZE to int when comparing with error code

* acpi-pm:
  ACPI / PM: save NVS memory for ASUS 1025C laptop
  ACPI / PM: Default to s2idle in all machines supporting LP S0

* pm-cpuidle:
  ARM: cpuidle: silence error on driver registration failure
This commit is contained in:
Rafael J. Wysocki 2018-08-14 09:48:10 +02:00
25 changed files with 186 additions and 89 deletions

View File

@ -114,18 +114,26 @@ Required properties:
- power-domains : A list of PM domain specifiers, as defined by bindings of
the power controller that is the PM domain provider.
Optional properties:
- power-domain-names : A list of power domain name strings sorted in the same
order as the power-domains property. Consumers drivers will use
power-domain-names to match power domains with power-domains
specifiers.
Example:
leaky-device@12350000 {
compatible = "foo,i-leak-current";
reg = <0x12350000 0x1000>;
power-domains = <&power 0>;
power-domain-names = "io";
};
leaky-device@12351000 {
compatible = "foo,i-leak-current";
reg = <0x12351000 0x1000>;
power-domains = <&power 0>, <&power 1> ;
power-domain-names = "io", "clk";
};
The first example above defines a typical PM domain consumer device, which is

View File

@ -81,10 +81,14 @@ integration is desired.
Two other flags are specifically targeted at use cases where the device
link is added from the consumer's ``->probe`` callback: ``DL_FLAG_RPM_ACTIVE``
can be specified to runtime resume the supplier upon addition of the
device link. ``DL_FLAG_AUTOREMOVE`` causes the device link to be automatically
purged when the consumer fails to probe or later unbinds. This obviates
the need to explicitly delete the link in the ``->remove`` callback or in
the error path of the ``->probe`` callback.
device link. ``DL_FLAG_AUTOREMOVE_CONSUMER`` causes the device link to be
automatically purged when the consumer fails to probe or later unbinds.
This obviates the need to explicitly delete the link in the ``->remove``
callback or in the error path of the ``->probe`` callback.
Similarly, when the device link is added from supplier's ``->probe`` callback,
``DL_FLAG_AUTOREMOVE_SUPPLIER`` causes the device link to be automatically
purged when the supplier fails to probe or later unbinds.
Limitations
===========

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@ -204,26 +204,26 @@ VI. Are there any precautions to be taken to prevent freezing failures?
Yes, there are.
First of all, grabbing the 'pm_mutex' lock to mutually exclude a piece of code
First of all, grabbing the 'system_transition_mutex' lock to mutually exclude a piece of code
from system-wide sleep such as suspend/hibernation is not encouraged.
If possible, that piece of code must instead hook onto the suspend/hibernation
notifiers to achieve mutual exclusion. Look at the CPU-Hotplug code
(kernel/cpu.c) for an example.
However, if that is not feasible, and grabbing 'pm_mutex' is deemed necessary,
it is strongly discouraged to directly call mutex_[un]lock(&pm_mutex) since
However, if that is not feasible, and grabbing 'system_transition_mutex' is deemed necessary,
it is strongly discouraged to directly call mutex_[un]lock(&system_transition_mutex) since
that could lead to freezing failures, because if the suspend/hibernate code
successfully acquired the 'pm_mutex' lock, and hence that other entity failed
successfully acquired the 'system_transition_mutex' lock, and hence that other entity failed
to acquire the lock, then that task would get blocked in TASK_UNINTERRUPTIBLE
state. As a consequence, the freezer would not be able to freeze that task,
leading to freezing failure.
However, the [un]lock_system_sleep() APIs are safe to use in this scenario,
since they ask the freezer to skip freezing this task, since it is anyway
"frozen enough" as it is blocked on 'pm_mutex', which will be released
"frozen enough" as it is blocked on 'system_transition_mutex', which will be released
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.
mutex_[un]lock(&system_transition_mutex). That would prevent freezing failures.
V. Miscellaneous
/sys/power/pm_freeze_timeout controls how long it will cost at most to freeze

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@ -32,7 +32,7 @@ More details follow:
sysfs file
|
v
Acquire pm_mutex lock
Acquire system_transition_mutex lock
|
v
Send PM_SUSPEND_PREPARE
@ -96,10 +96,10 @@ execution during resume):
* thaw tasks
* send PM_POST_SUSPEND notifications
* Release pm_mutex lock.
* Release system_transition_mutex lock.
It is to be noted here that the pm_mutex lock is acquired at the very
It is to be noted here that the system_transition_mutex lock is acquired at the very
beginning, when we are just starting out to suspend, and then released only
after the entire cycle is complete (i.e., suspend + resume).

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@ -233,29 +233,35 @@ struct restore_data_record {
*/
static int get_e820_md5(struct e820_table *table, void *buf)
{
struct scatterlist sg;
struct crypto_ahash *tfm;
struct crypto_shash *tfm;
struct shash_desc *desc;
int size;
int ret = 0;
tfm = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
tfm = crypto_alloc_shash("md5", 0, 0);
if (IS_ERR(tfm))
return -ENOMEM;
{
AHASH_REQUEST_ON_STACK(req, tfm);
size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry) * table->nr_entries;
ahash_request_set_tfm(req, tfm);
sg_init_one(&sg, (u8 *)table, size);
ahash_request_set_callback(req, 0, NULL, NULL);
ahash_request_set_crypt(req, &sg, buf, size);
if (crypto_ahash_digest(req))
ret = -EINVAL;
ahash_request_zero(req);
desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
GFP_KERNEL);
if (!desc) {
ret = -ENOMEM;
goto free_tfm;
}
crypto_free_ahash(tfm);
desc->tfm = tfm;
desc->flags = 0;
size = offsetof(struct e820_table, entries) +
sizeof(struct e820_entry) * table->nr_entries;
if (crypto_shash_digest(desc, (u8 *)table, size, buf))
ret = -EINVAL;
kzfree(desc);
free_tfm:
crypto_free_shash(tfm);
return ret;
}

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@ -338,6 +338,14 @@ static const struct dmi_system_id acpisleep_dmi_table[] __initconst = {
DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
},
},
{
.callback = init_nvs_save_s3,
.ident = "Asus 1025C",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
DMI_MATCH(DMI_PRODUCT_NAME, "1025C"),
},
},
/*
* https://bugzilla.kernel.org/show_bug.cgi?id=189431
* Lenovo G50-45 is a platform later than 2012, but needs nvs memory
@ -718,9 +726,6 @@ static const struct acpi_device_id lps0_device_ids[] = {
#define ACPI_LPS0_ENTRY 5
#define ACPI_LPS0_EXIT 6
#define ACPI_LPS0_SCREEN_MASK ((1 << ACPI_LPS0_SCREEN_OFF) | (1 << ACPI_LPS0_SCREEN_ON))
#define ACPI_LPS0_PLATFORM_MASK ((1 << ACPI_LPS0_ENTRY) | (1 << ACPI_LPS0_EXIT))
static acpi_handle lps0_device_handle;
static guid_t lps0_dsm_guid;
static char lps0_dsm_func_mask;
@ -924,17 +929,14 @@ static int lps0_device_attach(struct acpi_device *adev,
if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) {
char bitmask = *(char *)out_obj->buffer.pointer;
if ((bitmask & ACPI_LPS0_PLATFORM_MASK) == ACPI_LPS0_PLATFORM_MASK ||
(bitmask & ACPI_LPS0_SCREEN_MASK) == ACPI_LPS0_SCREEN_MASK) {
lps0_dsm_func_mask = bitmask;
lps0_device_handle = adev->handle;
/*
* Use suspend-to-idle by default if the default
* suspend mode was not set from the command line.
*/
if (mem_sleep_default > PM_SUSPEND_MEM)
mem_sleep_current = PM_SUSPEND_TO_IDLE;
}
lps0_dsm_func_mask = bitmask;
lps0_device_handle = adev->handle;
/*
* Use suspend-to-idle by default if the default
* suspend mode was not set from the command line.
*/
if (mem_sleep_default > PM_SUSPEND_MEM)
mem_sleep_current = PM_SUSPEND_TO_IDLE;
acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
bitmask);

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@ -178,10 +178,10 @@ void device_pm_move_to_tail(struct device *dev)
* of the link. If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be
* ignored.
*
* If the DL_FLAG_AUTOREMOVE is set, the link will be removed automatically
* when the consumer device driver unbinds from it. The combination of both
* DL_FLAG_AUTOREMOVE and DL_FLAG_STATELESS set is invalid and will cause NULL
* to be returned.
* If the DL_FLAG_AUTOREMOVE_CONSUMER is set, the link will be removed
* automatically when the consumer device driver unbinds from it.
* The combination of both DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_STATELESS
* set is invalid and will cause NULL to be returned.
*
* A side effect of the link creation is re-ordering of dpm_list and the
* devices_kset list by moving the consumer device and all devices depending
@ -198,7 +198,8 @@ struct device_link *device_link_add(struct device *consumer,
struct device_link *link;
if (!consumer || !supplier ||
((flags & DL_FLAG_STATELESS) && (flags & DL_FLAG_AUTOREMOVE)))
((flags & DL_FLAG_STATELESS) &&
(flags & DL_FLAG_AUTOREMOVE_CONSUMER)))
return NULL;
device_links_write_lock();
@ -479,7 +480,7 @@ static void __device_links_no_driver(struct device *dev)
if (link->flags & DL_FLAG_STATELESS)
continue;
if (link->flags & DL_FLAG_AUTOREMOVE)
if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
kref_put(&link->kref, __device_link_del);
else if (link->status != DL_STATE_SUPPLIER_UNBIND)
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
@ -515,8 +516,18 @@ void device_links_driver_cleanup(struct device *dev)
if (link->flags & DL_FLAG_STATELESS)
continue;
WARN_ON(link->flags & DL_FLAG_AUTOREMOVE);
WARN_ON(link->flags & DL_FLAG_AUTOREMOVE_CONSUMER);
WARN_ON(link->status != DL_STATE_SUPPLIER_UNBIND);
/*
* autoremove the links between this @dev and its consumer
* devices that are not active, i.e. where the link state
* has moved to DL_STATE_SUPPLIER_UNBIND.
*/
if (link->status == DL_STATE_SUPPLIER_UNBIND &&
link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
kref_put(&link->kref, __device_link_del);
WRITE_ONCE(link->status, DL_STATE_DORMANT);
}

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@ -152,6 +152,23 @@ struct device *dev_pm_domain_attach_by_id(struct device *dev,
}
EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_id);
/**
* dev_pm_domain_attach_by_name - Associate a device with one of its PM domains.
* @dev: The device used to lookup the PM domain.
* @name: The name of the PM domain.
*
* For a detailed function description, see dev_pm_domain_attach_by_id().
*/
struct device *dev_pm_domain_attach_by_name(struct device *dev,
char *name)
{
if (dev->pm_domain)
return ERR_PTR(-EEXIST);
return genpd_dev_pm_attach_by_name(dev, name);
}
EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_name);
/**
* dev_pm_domain_detach - Detach a device from its PM domain.
* @dev: Device to detach.

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@ -2374,6 +2374,30 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
}
EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
/**
* genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
* @dev: The device used to lookup the PM domain.
* @name: The name of the PM domain.
*
* Parse device's OF node to find a PM domain specifier using the
* power-domain-names DT property. For further description see
* genpd_dev_pm_attach_by_id().
*/
struct device *genpd_dev_pm_attach_by_name(struct device *dev, char *name)
{
int index;
if (!dev->of_node)
return NULL;
index = of_property_match_string(dev->of_node, "power-domain-names",
name);
if (index < 0)
return NULL;
return genpd_dev_pm_attach_by_id(dev, index);
}
static const struct of_device_id idle_state_match[] = {
{ .compatible = "domain-idle-state", },
{ }

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@ -105,7 +105,8 @@ static int __init arm_idle_init_cpu(int cpu)
ret = cpuidle_register_driver(drv);
if (ret) {
pr_err("Failed to register cpuidle driver\n");
if (ret != -EBUSY)
pr_err("Failed to register cpuidle driver\n");
goto out_kfree_drv;
}

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@ -2312,7 +2312,7 @@ static int tegra_dc_couple(struct tegra_dc *dc)
* POWER_CONTROL registers during CRTC enabling.
*/
if (dc->soc->coupled_pm && dc->pipe == 1) {
u32 flags = DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE;
u32 flags = DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_CONSUMER;
struct device_link *link;
struct device *partner;

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@ -128,7 +128,8 @@ ipu_pre_lookup_by_phandle(struct device *dev, const char *name, int index)
list_for_each_entry(pre, &ipu_pre_list, list) {
if (pre_node == pre->dev->of_node) {
mutex_unlock(&ipu_pre_list_mutex);
device_link_add(dev, pre->dev, DL_FLAG_AUTOREMOVE);
device_link_add(dev, pre->dev,
DL_FLAG_AUTOREMOVE_CONSUMER);
of_node_put(pre_node);
return pre;
}

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@ -100,7 +100,8 @@ ipu_prg_lookup_by_phandle(struct device *dev, const char *name, int ipu_id)
list_for_each_entry(prg, &ipu_prg_list, list) {
if (prg_node == prg->dev->of_node) {
mutex_unlock(&ipu_prg_list_mutex);
device_link_add(dev, prg->dev, DL_FLAG_AUTOREMOVE);
device_link_add(dev, prg->dev,
DL_FLAG_AUTOREMOVE_CONSUMER);
prg->id = ipu_id;
of_node_put(prg_node);
return prg;

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@ -209,7 +209,7 @@ static int imx_pgc_power_domain_probe(struct platform_device *pdev)
goto genpd_err;
}
device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE);
device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE_CONSUMER);
return 0;

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@ -90,7 +90,7 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
* @num_vf: Called to find out how many virtual functions a device on this
* bus supports.
* @dma_configure: Called to setup DMA configuration on a device on
this bus.
* this bus.
* @pm: Power management operations of this bus, callback the specific
* device driver's pm-ops.
* @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
@ -784,14 +784,16 @@ enum device_link_state {
* Device link flags.
*
* STATELESS: The core won't track the presence of supplier/consumer drivers.
* AUTOREMOVE: Remove this link automatically on consumer driver unbind.
* AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
* PM_RUNTIME: If set, the runtime PM framework will use this link.
* RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
* AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
*/
#define DL_FLAG_STATELESS BIT(0)
#define DL_FLAG_AUTOREMOVE BIT(1)
#define DL_FLAG_PM_RUNTIME BIT(2)
#define DL_FLAG_RPM_ACTIVE BIT(3)
#define DL_FLAG_STATELESS BIT(0)
#define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1)
#define DL_FLAG_PM_RUNTIME BIT(2)
#define DL_FLAG_RPM_ACTIVE BIT(3)
#define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4)
/**
* struct device_link - Device link representation.

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@ -239,6 +239,8 @@ unsigned int of_genpd_opp_to_performance_state(struct device *dev,
int genpd_dev_pm_attach(struct device *dev);
struct device *genpd_dev_pm_attach_by_id(struct device *dev,
unsigned int index);
struct device *genpd_dev_pm_attach_by_name(struct device *dev,
char *name);
#else /* !CONFIG_PM_GENERIC_DOMAINS_OF */
static inline int of_genpd_add_provider_simple(struct device_node *np,
struct generic_pm_domain *genpd)
@ -290,6 +292,12 @@ static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev,
return NULL;
}
static inline struct device *genpd_dev_pm_attach_by_name(struct device *dev,
char *name)
{
return NULL;
}
static inline
struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
{
@ -301,6 +309,8 @@ struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
int dev_pm_domain_attach(struct device *dev, bool power_on);
struct device *dev_pm_domain_attach_by_id(struct device *dev,
unsigned int index);
struct device *dev_pm_domain_attach_by_name(struct device *dev,
char *name);
void dev_pm_domain_detach(struct device *dev, bool power_off);
void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
#else
@ -313,6 +323,11 @@ static inline struct device *dev_pm_domain_attach_by_id(struct device *dev,
{
return NULL;
}
static inline struct device *dev_pm_domain_attach_by_name(struct device *dev,
char *name)
{
return NULL;
}
static inline void dev_pm_domain_detach(struct device *dev, bool power_off) {}
static inline void dev_pm_domain_set(struct device *dev,
struct dev_pm_domain *pd) {}

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@ -414,7 +414,7 @@ static inline bool hibernation_available(void) { return false; }
#define PM_RESTORE_PREPARE 0x0005 /* Going to restore a saved image */
#define PM_POST_RESTORE 0x0006 /* Restore failed */
extern struct mutex pm_mutex;
extern struct mutex system_transition_mutex;
#ifdef CONFIG_PM_SLEEP
void save_processor_state(void);

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@ -15,7 +15,9 @@
atomic_t system_freezing_cnt = ATOMIC_INIT(0);
EXPORT_SYMBOL(system_freezing_cnt);
/* indicate whether PM freezing is in effect, protected by pm_mutex */
/* indicate whether PM freezing is in effect, protected by
* system_transition_mutex
*/
bool pm_freezing;
bool pm_nosig_freezing;

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@ -338,7 +338,7 @@ static int create_image(int platform_mode)
* hibernation_snapshot - Quiesce devices and create a hibernation image.
* @platform_mode: If set, use platform driver to prepare for the transition.
*
* This routine must be called with pm_mutex held.
* This routine must be called with system_transition_mutex held.
*/
int hibernation_snapshot(int platform_mode)
{
@ -500,8 +500,9 @@ static int resume_target_kernel(bool platform_mode)
* hibernation_restore - Quiesce devices and restore from a hibernation image.
* @platform_mode: If set, use platform driver to prepare for the transition.
*
* This routine must be called with pm_mutex held. If it is successful, control
* reappears in the restored target kernel in hibernation_snapshot().
* This routine must be called with system_transition_mutex held. If it is
* successful, control reappears in the restored target kernel in
* hibernation_snapshot().
*/
int hibernation_restore(int platform_mode)
{
@ -638,6 +639,7 @@ static void power_down(void)
break;
case HIBERNATION_PLATFORM:
hibernation_platform_enter();
/* Fall through */
case HIBERNATION_SHUTDOWN:
if (pm_power_off)
kernel_power_off();
@ -805,13 +807,13 @@ static int software_resume(void)
* name_to_dev_t() below takes a sysfs buffer mutex when sysfs
* is configured into the kernel. Since the regular hibernate
* trigger path is via sysfs which takes a buffer mutex before
* calling hibernate functions (which take pm_mutex) this can
* cause lockdep to complain about a possible ABBA deadlock
* calling hibernate functions (which take system_transition_mutex)
* this can cause lockdep to complain about a possible ABBA deadlock
* which cannot happen since we're in the boot code here and
* sysfs can't be invoked yet. Therefore, we use a subclass
* here to avoid lockdep complaining.
*/
mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
if (swsusp_resume_device)
goto Check_image;
@ -899,7 +901,7 @@ static int software_resume(void)
atomic_inc(&snapshot_device_available);
/* For success case, the suspend path will release the lock */
Unlock:
mutex_unlock(&pm_mutex);
mutex_unlock(&system_transition_mutex);
pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
return error;
Close_Finish:

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@ -15,17 +15,16 @@
#include <linux/workqueue.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/suspend.h>
#include "power.h"
DEFINE_MUTEX(pm_mutex);
#ifdef CONFIG_PM_SLEEP
void lock_system_sleep(void)
{
current->flags |= PF_FREEZER_SKIP;
mutex_lock(&pm_mutex);
mutex_lock(&system_transition_mutex);
}
EXPORT_SYMBOL_GPL(lock_system_sleep);
@ -37,8 +36,9 @@ void unlock_system_sleep(void)
*
* Reason:
* Fundamentally, we just don't need it, because freezing condition
* doesn't come into effect until we release the pm_mutex lock,
* since the freezer always works with pm_mutex held.
* doesn't come into effect until we release the
* system_transition_mutex lock, since the freezer always works with
* system_transition_mutex held.
*
* More importantly, in the case of hibernation,
* unlock_system_sleep() gets called in snapshot_read() and
@ -47,7 +47,7 @@ void unlock_system_sleep(void)
* enter the refrigerator, thus causing hibernation to lockup.
*/
current->flags &= ~PF_FREEZER_SKIP;
mutex_unlock(&pm_mutex);
mutex_unlock(&system_transition_mutex);
}
EXPORT_SYMBOL_GPL(unlock_system_sleep);

View File

@ -556,7 +556,7 @@ static int enter_state(suspend_state_t state)
} else if (!valid_state(state)) {
return -EINVAL;
}
if (!mutex_trylock(&pm_mutex))
if (!mutex_trylock(&system_transition_mutex))
return -EBUSY;
if (state == PM_SUSPEND_TO_IDLE)
@ -590,7 +590,7 @@ static int enter_state(suspend_state_t state)
pm_pr_dbg("Finishing wakeup.\n");
suspend_finish();
Unlock:
mutex_unlock(&pm_mutex);
mutex_unlock(&system_transition_mutex);
return error;
}

View File

@ -923,7 +923,7 @@ int swsusp_write(unsigned int flags)
}
memset(&snapshot, 0, sizeof(struct snapshot_handle));
error = snapshot_read_next(&snapshot);
if (error < PAGE_SIZE) {
if (error < (int)PAGE_SIZE) {
if (error >= 0)
error = -EFAULT;
@ -1483,7 +1483,7 @@ int swsusp_read(unsigned int *flags_p)
memset(&snapshot, 0, sizeof(struct snapshot_handle));
error = snapshot_write_next(&snapshot);
if (error < PAGE_SIZE)
if (error < (int)PAGE_SIZE)
return error < 0 ? error : -EFAULT;
header = (struct swsusp_info *)data_of(snapshot);
error = get_swap_reader(&handle, flags_p);

View File

@ -216,7 +216,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!mutex_trylock(&pm_mutex))
if (!mutex_trylock(&system_transition_mutex))
return -EBUSY;
lock_device_hotplug();
@ -394,7 +394,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
}
unlock_device_hotplug();
mutex_unlock(&pm_mutex);
mutex_unlock(&system_transition_mutex);
return error;
}

View File

@ -294,7 +294,7 @@ void kernel_power_off(void)
}
EXPORT_SYMBOL_GPL(kernel_power_off);
static DEFINE_MUTEX(reboot_mutex);
DEFINE_MUTEX(system_transition_mutex);
/*
* Reboot system call: for obvious reasons only root may call it,
@ -338,7 +338,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
cmd = LINUX_REBOOT_CMD_HALT;
mutex_lock(&reboot_mutex);
mutex_lock(&system_transition_mutex);
switch (cmd) {
case LINUX_REBOOT_CMD_RESTART:
kernel_restart(NULL);
@ -389,7 +389,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
ret = -EINVAL;
break;
}
mutex_unlock(&reboot_mutex);
mutex_unlock(&system_transition_mutex);
return ret;
}

View File

@ -155,16 +155,17 @@ static inline void set_pcppage_migratetype(struct page *page, int migratetype)
* 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 pm_mutex held (gfp_allowed_mask also should
* only be modified with pm_mutex held, unless the suspend/hibernate code is
* guaranteed not to run in parallel with that modification).
* 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(&pm_mutex));
WARN_ON(!mutex_is_locked(&system_transition_mutex));
if (saved_gfp_mask) {
gfp_allowed_mask = saved_gfp_mask;
saved_gfp_mask = 0;
@ -173,7 +174,7 @@ void pm_restore_gfp_mask(void)
void pm_restrict_gfp_mask(void)
{
WARN_ON(!mutex_is_locked(&pm_mutex));
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);