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author | Ingo Molnar <mingo@elte.hu> | 2008-07-17 23:57:20 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-07-17 23:57:20 +0200 |
commit | 393d81aa026e19b6ede6f5f11955c97ee62e5df5 (patch) | |
tree | a1d9511e488e19d41089ff0a736f6ce52a81c6e5 /kernel/power | |
parent | 93a0886e2368eafb9df5e2021fb185195cee88b2 (diff) | |
parent | 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff) | |
download | linux-stable-393d81aa026e19b6ede6f5f11955c97ee62e5df5.tar.gz linux-stable-393d81aa026e19b6ede6f5f11955c97ee62e5df5.tar.bz2 linux-stable-393d81aa026e19b6ede6f5f11955c97ee62e5df5.zip |
Merge branch 'linus' into xen-64bit
Diffstat (limited to 'kernel/power')
-rw-r--r-- | kernel/power/disk.c | 50 | ||||
-rw-r--r-- | kernel/power/main.c | 16 | ||||
-rw-r--r-- | kernel/power/process.c | 97 | ||||
-rw-r--r-- | kernel/power/user.c | 71 |
4 files changed, 135 insertions, 99 deletions
diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 14a656cdc652..f011e0870b52 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -180,6 +180,17 @@ static void platform_restore_cleanup(int platform_mode) } /** + * platform_recover - recover the platform from a failure to suspend + * devices. + */ + +static void platform_recover(int platform_mode) +{ + if (platform_mode && hibernation_ops && hibernation_ops->recover) + hibernation_ops->recover(); +} + +/** * create_image - freeze devices that need to be frozen with interrupts * off, create the hibernation image and thaw those devices. Control * reappears in this routine after a restore. @@ -193,6 +204,7 @@ static int create_image(int platform_mode) if (error) return error; + device_pm_lock(); local_irq_disable(); /* At this point, device_suspend() has been called, but *not* * device_power_down(). We *must* call device_power_down() now. @@ -224,9 +236,11 @@ static int create_image(int platform_mode) /* NOTE: device_power_up() is just a resume() for devices * that suspended with irqs off ... no overall powerup. */ - device_power_up(); + device_power_up(in_suspend ? + (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); Enable_irqs: local_irq_enable(); + device_pm_unlock(); return error; } @@ -255,10 +269,10 @@ int hibernation_snapshot(int platform_mode) suspend_console(); error = device_suspend(PMSG_FREEZE); if (error) - goto Resume_console; + goto Recover_platform; if (hibernation_test(TEST_DEVICES)) - goto Resume_devices; + goto Recover_platform; error = platform_pre_snapshot(platform_mode); if (error || hibernation_test(TEST_PLATFORM)) @@ -280,12 +294,16 @@ int hibernation_snapshot(int platform_mode) Finish: platform_finish(platform_mode); Resume_devices: - device_resume(); - Resume_console: + device_resume(in_suspend ? + (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); resume_console(); Close: platform_end(platform_mode); return error; + + Recover_platform: + platform_recover(platform_mode); + goto Resume_devices; } /** @@ -300,8 +318,9 @@ static int resume_target_kernel(void) { int error; + device_pm_lock(); local_irq_disable(); - error = device_power_down(PMSG_PRETHAW); + error = device_power_down(PMSG_QUIESCE); if (error) { printk(KERN_ERR "PM: Some devices failed to power down, " "aborting resume\n"); @@ -329,9 +348,10 @@ static int resume_target_kernel(void) swsusp_free(); restore_processor_state(); touch_softlockup_watchdog(); - device_power_up(); + device_power_up(PMSG_RECOVER); Enable_irqs: local_irq_enable(); + device_pm_unlock(); return error; } @@ -350,7 +370,7 @@ int hibernation_restore(int platform_mode) pm_prepare_console(); suspend_console(); - error = device_suspend(PMSG_PRETHAW); + error = device_suspend(PMSG_QUIESCE); if (error) goto Finish; @@ -362,7 +382,7 @@ int hibernation_restore(int platform_mode) enable_nonboot_cpus(); } platform_restore_cleanup(platform_mode); - device_resume(); + device_resume(PMSG_RECOVER); Finish: resume_console(); pm_restore_console(); @@ -392,8 +412,11 @@ int hibernation_platform_enter(void) suspend_console(); error = device_suspend(PMSG_HIBERNATE); - if (error) - goto Resume_console; + if (error) { + if (hibernation_ops->recover) + hibernation_ops->recover(); + goto Resume_devices; + } error = hibernation_ops->prepare(); if (error) @@ -403,6 +426,7 @@ int hibernation_platform_enter(void) if (error) goto Finish; + device_pm_lock(); local_irq_disable(); error = device_power_down(PMSG_HIBERNATE); if (!error) { @@ -411,6 +435,7 @@ int hibernation_platform_enter(void) while (1); } local_irq_enable(); + device_pm_unlock(); /* * We don't need to reenable the nonboot CPUs or resume consoles, since @@ -419,8 +444,7 @@ int hibernation_platform_enter(void) Finish: hibernation_ops->finish(); Resume_devices: - device_resume(); - Resume_console: + device_resume(PMSG_RESTORE); resume_console(); Close: hibernation_ops->end(); diff --git a/kernel/power/main.c b/kernel/power/main.c index 6a6d5eb3524e..3398f4651aa1 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -228,6 +228,7 @@ static int suspend_enter(suspend_state_t state) { int error = 0; + device_pm_lock(); arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); @@ -239,10 +240,11 @@ static int suspend_enter(suspend_state_t state) if (!suspend_test(TEST_CORE)) error = suspend_ops->enter(state); - device_power_up(); + device_power_up(PMSG_RESUME); Done: arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); + device_pm_unlock(); return error; } @@ -267,11 +269,11 @@ int suspend_devices_and_enter(suspend_state_t state) error = device_suspend(PMSG_SUSPEND); if (error) { printk(KERN_ERR "PM: Some devices failed to suspend\n"); - goto Resume_console; + goto Recover_platform; } if (suspend_test(TEST_DEVICES)) - goto Resume_devices; + goto Recover_platform; if (suspend_ops->prepare) { error = suspend_ops->prepare(); @@ -291,13 +293,17 @@ int suspend_devices_and_enter(suspend_state_t state) if (suspend_ops->finish) suspend_ops->finish(); Resume_devices: - device_resume(); - Resume_console: + device_resume(PMSG_RESUME); resume_console(); Close: if (suspend_ops->end) suspend_ops->end(); return error; + + Recover_platform: + if (suspend_ops->recover) + suspend_ops->recover(); + goto Resume_devices; } /** diff --git a/kernel/power/process.c b/kernel/power/process.c index f1d0b345c9ba..5fb87652f214 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -19,9 +19,6 @@ */ #define TIMEOUT (20 * HZ) -#define FREEZER_KERNEL_THREADS 0 -#define FREEZER_USER_SPACE 1 - static inline int freezeable(struct task_struct * p) { if ((p == current) || @@ -84,63 +81,53 @@ static void fake_signal_wake_up(struct task_struct *p) spin_unlock_irqrestore(&p->sighand->siglock, flags); } -static int has_mm(struct task_struct *p) +static inline bool should_send_signal(struct task_struct *p) { - return (p->mm && !(p->flags & PF_BORROWED_MM)); + return !(p->flags & PF_FREEZER_NOSIG); } /** * freeze_task - send a freeze request to given task * @p: task to send the request to - * @with_mm_only: if set, the request will only be sent if the task has its - * own mm - * Return value: 0, if @with_mm_only is set and the task has no mm of its - * own or the task is frozen, 1, otherwise + * @sig_only: if set, the request will only be sent if the task has the + * PF_FREEZER_NOSIG flag unset + * Return value: 'false', if @sig_only is set and the task has + * PF_FREEZER_NOSIG set or the task is frozen, 'true', otherwise * - * The freeze request is sent by seting the tasks's TIF_FREEZE flag and + * The freeze request is sent by setting the tasks's TIF_FREEZE flag and * either sending a fake signal to it or waking it up, depending on whether - * or not it has its own mm (ie. it is a user land task). If @with_mm_only - * is set and the task has no mm of its own (ie. it is a kernel thread), - * its TIF_FREEZE flag should not be set. - * - * The task_lock() is necessary to prevent races with exit_mm() or - * use_mm()/unuse_mm() from occuring. + * or not it has PF_FREEZER_NOSIG set. If @sig_only is set and the task + * has PF_FREEZER_NOSIG set (ie. it is a typical kernel thread), its + * TIF_FREEZE flag will not be set. */ -static int freeze_task(struct task_struct *p, int with_mm_only) +static bool freeze_task(struct task_struct *p, bool sig_only) { - int ret = 1; + /* + * We first check if the task is freezing and next if it has already + * been frozen to avoid the race with frozen_process() which first marks + * the task as frozen and next clears its TIF_FREEZE. + */ + if (!freezing(p)) { + rmb(); + if (frozen(p)) + return false; - task_lock(p); - if (freezing(p)) { - if (has_mm(p)) { - if (!signal_pending(p)) - fake_signal_wake_up(p); - } else { - if (with_mm_only) - ret = 0; - else - wake_up_state(p, TASK_INTERRUPTIBLE); - } + if (!sig_only || should_send_signal(p)) + set_freeze_flag(p); + else + return false; + } + + if (should_send_signal(p)) { + if (!signal_pending(p)) + fake_signal_wake_up(p); + } else if (sig_only) { + return false; } else { - rmb(); - if (frozen(p)) { - ret = 0; - } else { - if (has_mm(p)) { - set_freeze_flag(p); - fake_signal_wake_up(p); - } else { - if (with_mm_only) { - ret = 0; - } else { - set_freeze_flag(p); - wake_up_state(p, TASK_INTERRUPTIBLE); - } - } - } + wake_up_state(p, TASK_INTERRUPTIBLE); } - task_unlock(p); - return ret; + + return true; } static void cancel_freezing(struct task_struct *p) @@ -156,7 +143,7 @@ static void cancel_freezing(struct task_struct *p) } } -static int try_to_freeze_tasks(int freeze_user_space) +static int try_to_freeze_tasks(bool sig_only) { struct task_struct *g, *p; unsigned long end_time; @@ -175,7 +162,7 @@ static int try_to_freeze_tasks(int freeze_user_space) if (frozen(p) || !freezeable(p)) continue; - if (!freeze_task(p, freeze_user_space)) + if (!freeze_task(p, sig_only)) continue; /* @@ -235,13 +222,13 @@ int freeze_processes(void) int error; printk("Freezing user space processes ... "); - error = try_to_freeze_tasks(FREEZER_USER_SPACE); + error = try_to_freeze_tasks(true); if (error) goto Exit; printk("done.\n"); printk("Freezing remaining freezable tasks ... "); - error = try_to_freeze_tasks(FREEZER_KERNEL_THREADS); + error = try_to_freeze_tasks(false); if (error) goto Exit; printk("done."); @@ -251,7 +238,7 @@ int freeze_processes(void) return error; } -static void thaw_tasks(int thaw_user_space) +static void thaw_tasks(bool nosig_only) { struct task_struct *g, *p; @@ -260,7 +247,7 @@ static void thaw_tasks(int thaw_user_space) if (!freezeable(p)) continue; - if (!p->mm == thaw_user_space) + if (nosig_only && should_send_signal(p)) continue; thaw_process(p); @@ -271,8 +258,8 @@ static void thaw_tasks(int thaw_user_space) void thaw_processes(void) { printk("Restarting tasks ... "); - thaw_tasks(FREEZER_KERNEL_THREADS); - thaw_tasks(FREEZER_USER_SPACE); + thaw_tasks(true); + thaw_tasks(false); schedule(); printk("done.\n"); } diff --git a/kernel/power/user.c b/kernel/power/user.c index f5512cb3aa86..a6332a313262 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -23,6 +23,7 @@ #include <linux/console.h> #include <linux/cpu.h> #include <linux/freezer.h> +#include <linux/smp_lock.h> #include <asm/uaccess.h> @@ -69,16 +70,22 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; - if (!atomic_add_unless(&snapshot_device_available, -1, 0)) - return -EBUSY; + mutex_lock(&pm_mutex); + + if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { + error = -EBUSY; + goto Unlock; + } if ((filp->f_flags & O_ACCMODE) == O_RDWR) { atomic_inc(&snapshot_device_available); - return -ENOSYS; + error = -ENOSYS; + goto Unlock; } if(create_basic_memory_bitmaps()) { atomic_inc(&snapshot_device_available); - return -ENOMEM; + error = -ENOMEM; + goto Unlock; } nonseekable_open(inode, filp); data = &snapshot_state; @@ -98,33 +105,36 @@ static int snapshot_open(struct inode *inode, struct file *filp) if (error) pm_notifier_call_chain(PM_POST_HIBERNATION); } - if (error) { + if (error) atomic_inc(&snapshot_device_available); - return error; - } data->frozen = 0; data->ready = 0; data->platform_support = 0; - return 0; + Unlock: + mutex_unlock(&pm_mutex); + + return error; } static int snapshot_release(struct inode *inode, struct file *filp) { struct snapshot_data *data; + mutex_lock(&pm_mutex); + swsusp_free(); free_basic_memory_bitmaps(); data = filp->private_data; free_all_swap_pages(data->swap); - if (data->frozen) { - mutex_lock(&pm_mutex); + if (data->frozen) thaw_processes(); - mutex_unlock(&pm_mutex); - } pm_notifier_call_chain(data->mode == O_WRONLY ? PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); + + mutex_unlock(&pm_mutex); + return 0; } @@ -134,9 +144,13 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, struct snapshot_data *data; ssize_t res; + mutex_lock(&pm_mutex); + data = filp->private_data; - if (!data->ready) - return -ENODATA; + if (!data->ready) { + res = -ENODATA; + goto Unlock; + } res = snapshot_read_next(&data->handle, count); if (res > 0) { if (copy_to_user(buf, data_of(data->handle), res)) @@ -144,6 +158,10 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, else *offp = data->handle.offset; } + + Unlock: + mutex_unlock(&pm_mutex); + return res; } @@ -153,6 +171,8 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, struct snapshot_data *data; ssize_t res; + mutex_lock(&pm_mutex); + data = filp->private_data; res = snapshot_write_next(&data->handle, count); if (res > 0) { @@ -161,11 +181,14 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, else *offp = data->handle.offset; } + + mutex_unlock(&pm_mutex); + return res; } -static int snapshot_ioctl(struct inode *inode, struct file *filp, - unsigned int cmd, unsigned long arg) +static long snapshot_ioctl(struct file *filp, unsigned int cmd, + unsigned long arg) { int error = 0; struct snapshot_data *data; @@ -179,6 +202,9 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (!mutex_trylock(&pm_mutex)) + return -EBUSY; + data = filp->private_data; switch (cmd) { @@ -186,7 +212,6 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, case SNAPSHOT_FREEZE: if (data->frozen) break; - mutex_lock(&pm_mutex); printk("Syncing filesystems ... "); sys_sync(); printk("done.\n"); @@ -194,7 +219,6 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, error = freeze_processes(); if (error) thaw_processes(); - mutex_unlock(&pm_mutex); if (!error) data->frozen = 1; break; @@ -202,9 +226,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, case SNAPSHOT_UNFREEZE: if (!data->frozen || data->ready) break; - mutex_lock(&pm_mutex); thaw_processes(); - mutex_unlock(&pm_mutex); data->frozen = 0; break; @@ -307,16 +329,11 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, error = -EPERM; break; } - if (!mutex_trylock(&pm_mutex)) { - error = -EBUSY; - break; - } /* * Tasks are frozen and the notifiers have been called with * PM_HIBERNATION_PREPARE */ error = suspend_devices_and_enter(PM_SUSPEND_MEM); - mutex_unlock(&pm_mutex); break; case SNAPSHOT_PLATFORM_SUPPORT: @@ -390,6 +407,8 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, } + mutex_unlock(&pm_mutex); + return error; } @@ -399,7 +418,7 @@ static const struct file_operations snapshot_fops = { .read = snapshot_read, .write = snapshot_write, .llseek = no_llseek, - .ioctl = snapshot_ioctl, + .unlocked_ioctl = snapshot_ioctl, }; static struct miscdevice snapshot_device = { |