Using [un]lock_system_sleep() is safer than directly using mutex_[un]lock() on 'pm_mutex', since the latter could lead to freezing failures. Hence convert all the present users of mutex_[un]lock(&pm_mutex) to use these safe APIs instead. Suggested-by: Tejun Heo <tj at kernel.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat at linux.vnet.ibm.com> --- kernel/kexec.c | 4 ++-- kernel/power/hibernate.c | 16 ++++++++-------- kernel/power/main.c | 4 ++-- kernel/power/suspend.c | 4 ++-- kernel/power/user.c | 16 ++++++++-------- 5 files changed, 22 insertions(+), 22 deletions(-) diff --git a/kernel/kexec.c b/kernel/kexec.c index dc7bc08..090ee10 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -1523,7 +1523,7 @@ int kernel_kexec(void) #ifdef CONFIG_KEXEC_JUMP if (kexec_image->preserve_context) { - mutex_lock(&pm_mutex); + lock_system_sleep(); pm_prepare_console(); error = freeze_processes(); if (error) { @@ -1576,7 +1576,7 @@ int kernel_kexec(void) thaw_processes(); Restore_console: pm_restore_console(); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } #endif diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 605149a..6d6d288 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -69,14 +69,14 @@ void hibernation_set_ops(const struct platform_hibernation_ops *ops) WARN_ON(1); return; } - mutex_lock(&pm_mutex); + lock_system_sleep(); hibernation_ops = ops; if (ops) hibernation_mode = HIBERNATION_PLATFORM; else if (hibernation_mode == HIBERNATION_PLATFORM) hibernation_mode = HIBERNATION_SHUTDOWN; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } static bool entering_platform_hibernation; @@ -597,7 +597,7 @@ int hibernate(void) { int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); /* The snapshot device should not be opened while we're running */ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -665,7 +665,7 @@ int hibernate(void) pm_restore_console(); atomic_inc(&snapshot_device_available); Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -893,7 +893,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - mutex_lock(&pm_mutex); + lock_system_sleep(); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (len == strlen(hibernation_modes[i]) && !strncmp(buf, hibernation_modes[i], len)) { @@ -919,7 +919,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, if (!error) pr_debug("PM: Hibernation mode set to '%s'\n", hibernation_modes[mode]); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error ? error : n; } @@ -946,9 +946,9 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, if (maj != MAJOR(res) || min != MINOR(res)) goto out; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_resume_device = res; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); printk(KERN_INFO "PM: Starting manual resume from disk\n"); noresume = 0; software_resume(); diff --git a/kernel/power/main.c b/kernel/power/main.c index 7d36fb3..9824b41e 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -116,7 +116,7 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - mutex_lock(&pm_mutex); + lock_system_sleep(); level = TEST_FIRST; for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) @@ -126,7 +126,7 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, break; } - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error ? error : n; } diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index d336b27..4fd51be 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -42,9 +42,9 @@ static const struct platform_suspend_ops *suspend_ops; */ void suspend_set_ops(const struct platform_suspend_ops *ops) { - mutex_lock(&pm_mutex); + lock_system_sleep(); suspend_ops = ops; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } EXPORT_SYMBOL_GPL(suspend_set_ops); diff --git a/kernel/power/user.c b/kernel/power/user.c index 06ea33d..98ade21 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -71,7 +71,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -123,7 +123,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) data->platform_support = 0; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -132,7 +132,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) { struct snapshot_data *data; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_free(); free_basic_memory_bitmaps(); @@ -146,7 +146,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return 0; } @@ -158,7 +158,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; if (!data->ready) { @@ -179,7 +179,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, *offp += res; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; } @@ -191,7 +191,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; @@ -208,7 +208,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, if (res > 0) *offp += res; unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; }