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authorLinus Torvalds <torvalds@linux-foundation.org>2012-04-04 14:26:40 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-04-04 14:26:40 -0700
commit64ebe987311853ea857a244439de5b947a4b1b07 (patch)
treeb33ab6efd7f118e0f6ab5a6bcbd59ba31a313da5
parenta5149bf3fed59b94207809704b5d06fec337a771 (diff)
parentc4772d192c70b61d52262b0db76f7abd8aeb51c6 (diff)
downloadlinux-64ebe987311853ea857a244439de5b947a4b1b07.tar.gz
Merge tag 'pm-for-3.4-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki: - Patch series that hopefully fixes races between the freezer and request_firmware() and request_firmware_nowait() for good, with two cleanups from Stephen Boyd on top. - Runtime PM fix from Alan Stern preventing tasks from getting stuck indefinitely in the runtime PM wait queue. - Device PM QoS update from MyungJoo Ham introducing a new variant of pm_qos_update_request() allowing the callers to specify a timeout. * tag 'pm-for-3.4-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / QoS: add pm_qos_update_request_timeout() API firmware_class: Move request_firmware_nowait() to workqueues firmware_class: Reorganize fw_create_instance() PM / Sleep: Mitigate race between the freezer and request_firmware() PM / Sleep: Move disabling of usermode helpers to the freezer PM / Hibernate: Disable usermode helpers right before freezing tasks firmware_class: Do not warn that system is not ready from async loads firmware_class: Split _request_firmware() into three functions, v2 firmware_class: Rework usermodehelper check PM / Runtime: don't forget to wake up waitqueue on failure
-rw-r--r--drivers/base/firmware_class.c208
-rw-r--r--drivers/base/power/runtime.c3
-rw-r--r--include/linux/kmod.h27
-rw-r--r--include/linux/pm_qos.h4
-rw-r--r--kernel/kmod.c117
-rw-r--r--kernel/power/hibernate.c18
-rw-r--r--kernel/power/process.c8
-rw-r--r--kernel/power/qos.c50
-rw-r--r--kernel/power/suspend.c7
-rw-r--r--kernel/power/user.c10
10 files changed, 284 insertions, 168 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 6c9387d646e..5401814c874 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -16,10 +16,11 @@
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
-#include <linux/kthread.h>
+#include <linux/workqueue.h>
#include <linux/highmem.h>
#include <linux/firmware.h>
#include <linux/slab.h>
+#include <linux/sched.h>
#define to_dev(obj) container_of(obj, struct device, kobj)
@@ -81,6 +82,11 @@ enum {
static int loading_timeout = 60; /* In seconds */
+static inline long firmware_loading_timeout(void)
+{
+ return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
+}
+
/* fw_lock could be moved to 'struct firmware_priv' but since it is just
* guarding for corner cases a global lock should be OK */
static DEFINE_MUTEX(fw_lock);
@@ -440,13 +446,11 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
{
struct firmware_priv *fw_priv;
struct device *f_dev;
- int error;
fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
if (!fw_priv) {
dev_err(device, "%s: kmalloc failed\n", __func__);
- error = -ENOMEM;
- goto err_out;
+ return ERR_PTR(-ENOMEM);
}
fw_priv->fw = firmware;
@@ -463,98 +467,80 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
f_dev->parent = device;
f_dev->class = &firmware_class;
- dev_set_uevent_suppress(f_dev, true);
-
- /* Need to pin this module until class device is destroyed */
- __module_get(THIS_MODULE);
-
- error = device_add(f_dev);
- if (error) {
- dev_err(device, "%s: device_register failed\n", __func__);
- goto err_put_dev;
- }
-
- error = device_create_bin_file(f_dev, &firmware_attr_data);
- if (error) {
- dev_err(device, "%s: sysfs_create_bin_file failed\n", __func__);
- goto err_del_dev;
- }
-
- error = device_create_file(f_dev, &dev_attr_loading);
- if (error) {
- dev_err(device, "%s: device_create_file failed\n", __func__);
- goto err_del_bin_attr;
- }
-
- if (uevent)
- dev_set_uevent_suppress(f_dev, false);
-
return fw_priv;
-
-err_del_bin_attr:
- device_remove_bin_file(f_dev, &firmware_attr_data);
-err_del_dev:
- device_del(f_dev);
-err_put_dev:
- put_device(f_dev);
-err_out:
- return ERR_PTR(error);
}
-static void fw_destroy_instance(struct firmware_priv *fw_priv)
-{
- struct device *f_dev = &fw_priv->dev;
-
- device_remove_file(f_dev, &dev_attr_loading);
- device_remove_bin_file(f_dev, &firmware_attr_data);
- device_unregister(f_dev);
-}
-
-static int _request_firmware(const struct firmware **firmware_p,
- const char *name, struct device *device,
- bool uevent, bool nowait)
+static struct firmware_priv *
+_request_firmware_prepare(const struct firmware **firmware_p, const char *name,
+ struct device *device, bool uevent, bool nowait)
{
- struct firmware_priv *fw_priv;
struct firmware *firmware;
- int retval = 0;
+ struct firmware_priv *fw_priv;
if (!firmware_p)
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
if (!firmware) {
dev_err(device, "%s: kmalloc(struct firmware) failed\n",
__func__);
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
}
if (fw_get_builtin_firmware(firmware, name)) {
dev_dbg(device, "firmware: using built-in firmware %s\n", name);
- return 0;
+ return NULL;
+ }
+
+ fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
+ if (IS_ERR(fw_priv)) {
+ release_firmware(firmware);
+ *firmware_p = NULL;
}
+ return fw_priv;
+}
- read_lock_usermodehelper();
+static void _request_firmware_cleanup(const struct firmware **firmware_p)
+{
+ release_firmware(*firmware_p);
+ *firmware_p = NULL;
+}
- if (WARN_ON(usermodehelper_is_disabled())) {
- dev_err(device, "firmware: %s will not be loaded\n", name);
- retval = -EBUSY;
- goto out;
+static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
+ long timeout)
+{
+ int retval = 0;
+ struct device *f_dev = &fw_priv->dev;
+
+ dev_set_uevent_suppress(f_dev, true);
+
+ /* Need to pin this module until class device is destroyed */
+ __module_get(THIS_MODULE);
+
+ retval = device_add(f_dev);
+ if (retval) {
+ dev_err(f_dev, "%s: device_register failed\n", __func__);
+ goto err_put_dev;
}
- if (uevent)
- dev_dbg(device, "firmware: requesting %s\n", name);
+ retval = device_create_bin_file(f_dev, &firmware_attr_data);
+ if (retval) {
+ dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
+ goto err_del_dev;
+ }
- fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
- if (IS_ERR(fw_priv)) {
- retval = PTR_ERR(fw_priv);
- goto out;
+ retval = device_create_file(f_dev, &dev_attr_loading);
+ if (retval) {
+ dev_err(f_dev, "%s: device_create_file failed\n", __func__);
+ goto err_del_bin_attr;
}
if (uevent) {
- if (loading_timeout > 0)
+ dev_set_uevent_suppress(f_dev, false);
+ dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_id);
+ if (timeout != MAX_SCHEDULE_TIMEOUT)
mod_timer(&fw_priv->timeout,
- round_jiffies_up(jiffies +
- loading_timeout * HZ));
+ round_jiffies_up(jiffies + timeout));
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
@@ -570,16 +556,13 @@ static int _request_firmware(const struct firmware **firmware_p,
fw_priv->fw = NULL;
mutex_unlock(&fw_lock);
- fw_destroy_instance(fw_priv);
-
-out:
- read_unlock_usermodehelper();
-
- if (retval) {
- release_firmware(firmware);
- *firmware_p = NULL;
- }
-
+ device_remove_file(f_dev, &dev_attr_loading);
+err_del_bin_attr:
+ device_remove_bin_file(f_dev, &firmware_attr_data);
+err_del_dev:
+ device_del(f_dev);
+err_put_dev:
+ put_device(f_dev);
return retval;
}
@@ -602,7 +585,26 @@ int
request_firmware(const struct firmware **firmware_p, const char *name,
struct device *device)
{
- return _request_firmware(firmware_p, name, device, true, false);
+ struct firmware_priv *fw_priv;
+ int ret;
+
+ fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
+ false);
+ if (IS_ERR_OR_NULL(fw_priv))
+ return PTR_RET(fw_priv);
+
+ ret = usermodehelper_read_trylock();
+ if (WARN_ON(ret)) {
+ dev_err(device, "firmware: %s will not be loaded\n", name);
+ } else {
+ ret = _request_firmware_load(fw_priv, true,
+ firmware_loading_timeout());
+ usermodehelper_read_unlock();
+ }
+ if (ret)
+ _request_firmware_cleanup(firmware_p);
+
+ return ret;
}
/**
@@ -629,25 +631,39 @@ struct firmware_work {
bool uevent;
};
-static int request_firmware_work_func(void *arg)
+static void request_firmware_work_func(struct work_struct *work)
{
- struct firmware_work *fw_work = arg;
+ struct firmware_work *fw_work;
const struct firmware *fw;
+ struct firmware_priv *fw_priv;
+ long timeout;
int ret;
- if (!arg) {
- WARN_ON(1);
- return 0;
+ fw_work = container_of(work, struct firmware_work, work);
+ fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
+ fw_work->uevent, true);
+ if (IS_ERR_OR_NULL(fw_priv)) {
+ ret = PTR_RET(fw_priv);
+ goto out;
+ }
+
+ timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
+ if (timeout) {
+ ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
+ usermodehelper_read_unlock();
+ } else {
+ dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
+ fw_work->name);
+ ret = -EAGAIN;
}
+ if (ret)
+ _request_firmware_cleanup(&fw);
- ret = _request_firmware(&fw, fw_work->name, fw_work->device,
- fw_work->uevent, true);
+ out:
fw_work->cont(fw, fw_work->context);
module_put(fw_work->module);
kfree(fw_work);
-
- return ret;
}
/**
@@ -673,7 +689,6 @@ request_firmware_nowait(
const char *name, struct device *device, gfp_t gfp, void *context,
void (*cont)(const struct firmware *fw, void *context))
{
- struct task_struct *task;
struct firmware_work *fw_work;
fw_work = kzalloc(sizeof (struct firmware_work), gfp);
@@ -692,15 +707,8 @@ request_firmware_nowait(
return -EFAULT;
}
- task = kthread_run(request_firmware_work_func, fw_work,
- "firmware/%s", name);
- if (IS_ERR(task)) {
- fw_work->cont(NULL, fw_work->context);
- module_put(fw_work->module);
- kfree(fw_work);
- return PTR_ERR(task);
- }
-
+ INIT_WORK(&fw_work->work, request_firmware_work_func);
+ schedule_work(&fw_work->work);
return 0;
}
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 541f821d4ea..bd0f3949bcf 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -532,6 +532,8 @@ static int rpm_suspend(struct device *dev, int rpmflags)
dev->power.suspend_time = ktime_set(0, 0);
dev->power.max_time_suspended_ns = -1;
dev->power.deferred_resume = false;
+ wake_up_all(&dev->power.wait_queue);
+
if (retval == -EAGAIN || retval == -EBUSY) {
dev->power.runtime_error = 0;
@@ -547,7 +549,6 @@ static int rpm_suspend(struct device *dev, int rpmflags)
} else {
pm_runtime_cancel_pending(dev);
}
- wake_up_all(&dev->power.wait_queue);
goto out;
}
diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index 9efeae67910..dd99c329e16 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -110,12 +110,29 @@ call_usermodehelper(char *path, char **argv, char **envp, int wait)
extern struct ctl_table usermodehelper_table[];
+enum umh_disable_depth {
+ UMH_ENABLED = 0,
+ UMH_FREEZING,
+ UMH_DISABLED,
+};
+
extern void usermodehelper_init(void);
-extern int usermodehelper_disable(void);
-extern void usermodehelper_enable(void);
-extern bool usermodehelper_is_disabled(void);
-extern void read_lock_usermodehelper(void);
-extern void read_unlock_usermodehelper(void);
+extern int __usermodehelper_disable(enum umh_disable_depth depth);
+extern void __usermodehelper_set_disable_depth(enum umh_disable_depth depth);
+
+static inline int usermodehelper_disable(void)
+{
+ return __usermodehelper_disable(UMH_DISABLED);
+}
+
+static inline void usermodehelper_enable(void)
+{
+ __usermodehelper_set_disable_depth(UMH_ENABLED);
+}
+
+extern int usermodehelper_read_trylock(void);
+extern long usermodehelper_read_lock_wait(long timeout);
+extern void usermodehelper_read_unlock(void);
#endif /* __LINUX_KMOD_H__ */
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 2e9191a712f..233149cb19f 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -8,6 +8,7 @@
#include <linux/notifier.h>
#include <linux/miscdevice.h>
#include <linux/device.h>
+#include <linux/workqueue.h>
enum {
PM_QOS_RESERVED = 0,
@@ -29,6 +30,7 @@ enum {
struct pm_qos_request {
struct plist_node node;
int pm_qos_class;
+ struct delayed_work work; /* for pm_qos_update_request_timeout */
};
struct dev_pm_qos_request {
@@ -73,6 +75,8 @@ void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
s32 value);
void pm_qos_update_request(struct pm_qos_request *req,
s32 new_value);
+void pm_qos_update_request_timeout(struct pm_qos_request *req,
+ s32 new_value, unsigned long timeout_us);
void pm_qos_remove_request(struct pm_qos_request *req);
int pm_qos_request(int pm_qos_class);
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 957a7aab8eb..05698a7415f 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -322,7 +322,7 @@ static void __call_usermodehelper(struct work_struct *work)
* land has been frozen during a system-wide hibernation or suspend operation).
* Should always be manipulated under umhelper_sem acquired for write.
*/
-static int usermodehelper_disabled = 1;
+static enum umh_disable_depth usermodehelper_disabled = UMH_DISABLED;
/* Number of helpers running */
static atomic_t running_helpers = ATOMIC_INIT(0);
@@ -334,32 +334,110 @@ static atomic_t running_helpers = ATOMIC_INIT(0);
static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
/*
+ * Used by usermodehelper_read_lock_wait() to wait for usermodehelper_disabled
+ * to become 'false'.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq);
+
+/*
* Time to wait for running_helpers to become zero before the setting of
* usermodehelper_disabled in usermodehelper_disable() fails
*/
#define RUNNING_HELPERS_TIMEOUT (5 * HZ)
-void read_lock_usermodehelper(void)
+int usermodehelper_read_trylock(void)
{
+ DEFINE_WAIT(wait);
+ int ret = 0;
+
down_read(&umhelper_sem);
+ for (;;) {
+ prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
+ TASK_INTERRUPTIBLE);
+ if (!usermodehelper_disabled)
+ break;
+
+ if (usermodehelper_disabled == UMH_DISABLED)
+ ret = -EAGAIN;
+
+ up_read(&umhelper_sem);
+
+ if (ret)
+ break;
+
+ schedule();
+ try_to_freeze();
+
+ down_read(&umhelper_sem);
+ }
+ finish_wait(&usermodehelper_disabled_waitq, &wait);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usermodehelper_read_trylock);
+
+long usermodehelper_read_lock_wait(long timeout)
+{
+ DEFINE_WAIT(wait);
+
+ if (timeout < 0)
+ return -EINVAL;
+
+ down_read(&umhelper_sem);
+ for (;;) {
+ prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
+ TASK_UNINTERRUPTIBLE);
+ if (!usermodehelper_disabled)
+ break;
+
+ up_read(&umhelper_sem);
+
+ timeout = schedule_timeout(timeout);
+ if (!timeout)
+ break;
+
+ down_read(&umhelper_sem);
+ }
+ finish_wait(&usermodehelper_disabled_waitq, &wait);
+ return timeout;
}
-EXPORT_SYMBOL_GPL(read_lock_usermodehelper);
+EXPORT_SYMBOL_GPL(usermodehelper_read_lock_wait);
-void read_unlock_usermodehelper(void)
+void usermodehelper_read_unlock(void)
{
up_read(&umhelper_sem);
}
-EXPORT_SYMBOL_GPL(read_unlock_usermodehelper);
+EXPORT_SYMBOL_GPL(usermodehelper_read_unlock);
/**
- * usermodehelper_disable - prevent new helpers from being started
+ * __usermodehelper_set_disable_depth - Modify usermodehelper_disabled.
+ * depth: New value to assign to usermodehelper_disabled.
+ *
+ * Change the value of usermodehelper_disabled (under umhelper_sem locked for
+ * writing) and wakeup tasks waiting for it to change.
*/
-int usermodehelper_disable(void)
+void __usermodehelper_set_disable_depth(enum umh_disable_depth depth)
+{
+ down_write(&umhelper_sem);
+ usermodehelper_disabled = depth;
+ wake_up(&usermodehelper_disabled_waitq);
+ up_write(&umhelper_sem);
+}
+
+/**
+ * __usermodehelper_disable - Prevent new helpers from being started.
+ * @depth: New value to assign to usermodehelper_disabled.
+ *
+ * Set usermodehelper_disabled to @depth and wait for running helpers to exit.
+ */
+int __usermodehelper_disable(enum umh_disable_depth depth)
{
long retval;
+ if (!depth)
+ return -EINVAL;
+
down_write(&umhelper_sem);
- usermodehelper_disabled = 1;
+ usermodehelper_disabled = depth;
up_write(&umhelper_sem);
/*
@@ -374,31 +452,10 @@ int usermodehelper_disable(void)
if (retval)
return 0;
- down_write(&umhelper_sem);
- usermodehelper_disabled = 0;
- up_write(&umhelper_sem);
+ __usermodehelper_set_disable_depth(UMH_ENABLED);
return -EAGAIN;
}
-/**
- * usermodehelper_enable - allow new helpers to be started again
- */
-void usermodehelper_enable(void)
-{
- down_write(&umhelper_sem);
- usermodehelper_disabled = 0;
- up_write(&umhelper_sem);
-}
-
-/**
- * usermodehelper_is_disabled - check if new helpers are allowed to be started
- */
-bool usermodehelper_is_disabled(void)
-{
- return usermodehelper_disabled;
-}
-EXPORT_SYMBOL_GPL(usermodehelper_is_disabled);
-
static void helper_lock(void)
{
atomic_inc(&running_helpers);
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 0a186cfde78..e09dfbfeece 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -16,7 +16,6 @@
#include <linux/string.h>
#include <linux/device.h>
#include <linux/async.h>
-#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/mount.h>
@@ -611,14 +610,10 @@ int hibernate(void)
if (error)
goto Exit;
- error = usermodehelper_disable();
- if (error)
- goto Exit;
-
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
- goto Enable_umh;
+ goto Exit;
printk(KERN_INFO "PM: Syncing filesystems ... ");
sys_sync();
@@ -661,8 +656,6 @@ int hibernate(void)
Free_bitmaps:
free_basic_memory_bitmaps();
- Enable_umh:
- usermodehelper_enable();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
pm_restore_console();
@@ -777,15 +770,9 @@ static int software_resume(void)
if (error)
goto close_finish;
- error = usermodehelper_disable();
- if (error)
- goto close_finish;
-
error = create_basic_memory_bitmaps();
- if (error) {
- usermodehelper_enable();
+ if (error)
goto close_finish;
- }
pr_debug("PM: Preparing processes for restore.\n");
error = freeze_processes();
@@ -806,7 +793,6 @@ static int software_resume(void)
thaw_processes();
Done:
free_basic_memory_bitmaps();
- usermodehelper_enable();
Finish:
pm_notifier_call_chain(PM_POST_RESTORE);
pm_restore_console();
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 0d2aeb22610..19db29f6755 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -16,6 +16,7 @@
#include <linux/freezer.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
+#include <linux/kmod.h>
/*
* Timeout for stopping processes
@@ -122,6 +123,10 @@ int freeze_processes(void)
{
int error;
+ error = __usermodehelper_disable(UMH_FREEZING);
+ if (error)
+ return error;
+
if (!pm_freezing)
atomic_inc(&system_freezing_cnt);
@@ -130,6 +135,7 @@ int freeze_processes(void)
error = try_to_freeze_tasks(true);
if (!error) {
printk("done.");
+ __usermodehelper_set_disable_depth(UMH_DISABLED);
oom_killer_disable();
}
printk("\n");
@@ -187,6 +193,8 @@ void thaw_processes(void)
} while_each_thread(g, p);
read_unlock(&tasklist_lock);
+ usermodehelper_enable();
+
schedule();
printk("done.\n");
}
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index d6d6dbd1ecc..6a031e68402 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -230,6 +230,21 @@ int pm_qos_request_active(struct pm_qos_request *req)
EXPORT_SYMBOL_GPL(pm_qos_request_active);
/**
+ * pm_qos_work_fn - the timeout handler of pm_qos_update_request_timeout
+ * @work: work struct for the delayed work (timeout)
+ *
+ * This cancels the timeout request by falling back to the default at timeout.
+ */
+static void pm_qos_work_fn(struct work_struct *work)
+{
+ struct pm_qos_request *req = container_of(to_delayed_work(work),
+ struct pm_qos_request,
+ work);
+
+ pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE);
+}
+
+/**
* pm_qos_add_request - inserts new qos request into the list
* @req: pointer to a preallocated handle
* @pm_qos_class: identifies which list of qos request to use
@@ -253,6 +268,7 @@ void pm_qos_add_request(struct pm_qos_request *req,
return;
}
req->pm_qos_class = pm_qos_class;
+ INIT_DELAYED_WORK(&req->work, pm_qos_work_fn);
pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints,
&req->node, PM_QOS_ADD_REQ, value);
}
@@ -279,6 +295,9 @@ void pm_qos_update_request(struct pm_qos_request *req,
return;
}
+ if (delayed_work_pending(&req->work))
+ cancel_delayed_work_sync(&req->work);
+
if (new_value != req->node.prio)
pm_qos_update_target(
pm_qos_array[req->pm_qos_class]->constraints,
@@ -287,6 +306,34 @@ void pm_qos_update_request(struct pm_qos_request *req,
EXPORT_SYMBOL_GPL(pm_qos_update_request);
/**
+ * pm_qos_update_request_timeout - modifies an existing qos request temporarily.
+ * @req : handle to list element holding a pm_qos request to use
+ * @new_value: defines the temporal qos request
+ * @timeout_us: the effective duration of this qos request in usecs.
+ *
+ * After timeout_us, this qos request is cancelled automatically.
+ */
+void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value,
+ unsigned long timeout_us)
+{
+ if (!req)
+ return;
+ if (WARN(!pm_qos_request_active(req),
+ "%s called for unknown object.", __func__))
+ return;
+
+ if (delayed_work_pending(&req->work))
+ cancel_delayed_work_sync(&req->work);
+
+ if (new_value != req->node.prio)
+ pm_qos_update_target(
+ pm_qos_array[req->pm_qos_class]->constraints,
+ &req->node, PM_QOS_UPDATE_REQ, new_value);
+
+ schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us));
+}
+
+/**
* pm_qos_remove_request - modifies an existing qos request
* @req: handle to request list element
*
@@ -305,6 +352,9 @@ void pm_qos_remove_request(struct pm_qos_request *req)
return;
}
+ if (delayed_work_pending(&req->work))
+ cancel_delayed_work_sync(&req->work);
+
pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints,
&req->node, PM_QOS_REMOVE_REQ,
PM_QOS_DEFAULT_VALUE);
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 88e5c967370..396d262b8fd 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -12,7 +12,6 @@
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
-#include <linux/kmod.h>
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/syscalls.h>
@@ -102,17 +101,12 @@ static int suspend_prepare(void)
if (error)
goto Finish;
- error = usermodehelper_disable();
- if (error)
- goto Finish;
-
error = suspend_freeze_processes();
if (!error)
return 0;
suspend_stats.failed_freeze++;
dpm_save_failed_step(SUSPEND_FREEZE);
- usermodehelper_enable();
Finish:
pm_notifier_call_chain(PM_POST_SUSPEND);
pm_restore_console();
@@ -259,7 +253,6 @@ int suspend_devices_and_enter(suspend_state_t state)
static void suspend_finish(void)
{
suspend_thaw_processes();
- usermodehelper_enable();
pm_notifier_call_chain(PM_POST_SUSPEND);
pm_restore_console();
}
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 33c4329205a..91b0fd021a9 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -12,7 +12,6 @@
#include <linux/suspend.h>
#include <linux/syscalls.h>
#include <linux/reboot.h>
-#include <linux/kmod.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
@@ -222,14 +221,8 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
sys_sync();
printk("done.\n");
- error = usermodehelper_disable();
- if (error)
- break;
-
error = freeze_processes();
- if (error)
- usermodehelper_enable();
- else
+ if (!error)
data->frozen = 1;
break;
@@ -238,7 +231,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
break;
pm_restore_gfp_mask();
thaw_processes();
- usermodehelper_enable();
data->frozen = 0;
break;