On Wed, Dec 07, 2011 at 12:54:02AM +0530, Srivatsa S. Bhat wrote:
> 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>
I am happy with this from a kexec point of view.
Reviewed-by: Simon Horman <horms at verge.net.au>
> ---
>
> 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;
> }
>
>
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>
