diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/kmod.c | 117 | ||||
| -rw-r--r-- | kernel/power/hibernate.c | 18 | ||||
| -rw-r--r-- | kernel/power/process.c | 8 | ||||
| -rw-r--r-- | kernel/power/qos.c | 50 | ||||
| -rw-r--r-- | kernel/power/suspend.c | 7 | ||||
| -rw-r--r-- | kernel/power/user.c | 10 |
6 files changed, 148 insertions, 62 deletions
diff --git a/kernel/kmod.c b/kernel/kmod.c index 957a7aab8ebc..05698a7415fe 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 0a186cfde788..e09dfbfeecee 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 0d2aeb226108..19db29f67558 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 d6d6dbd1ecc0..6a031e684026 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 88e5c967370d..396d262b8fd0 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 33c4329205af..91b0fd021a95 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; |