[RFC][PATCH -mm 3/5] swsusp: Change code ordering in user.c

Rafael J. Wysocki
2006-11-25T21:38:27Z

Change the ordering of code in kernel/power/user.c so that device_suspend()
is called before disable_nonboot_cpus() and device_resume() is called after
enable_nonboot_cpus().

The changes here only affect the userland interface of swsusp.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/user.c | 92 ++++++++++++++++++++++++++++++++--------------------
1 file changed, 58 insertions(+), 34 deletions(-)

Index: linux-2.6.19-rc6-mm1/kernel/power/user.c
===================================================================
--- linux-2.6.19-rc6-mm1.orig/kernel/power/user.c
+++ linux-2.6.19-rc6-mm1/kernel/power/user.c
@@ -122,6 +122,59 @@ static ssize_t snapshot_write(struct fil
return res;
}

+static int snapshot_suspend(void)
+{
+ int error;
+
+ mutex_lock(&pm_mutex);
+ /* Free memory before shutting down devices. */
+ error = swsusp_shrink_memory();
+ if (error)
+ goto Finish;
+
+ suspend_console();
+ error = device_suspend(PMSG_FREEZE);
+ if (error)
+ goto Resume_devices;
+
+ error = disable_nonboot_cpus();
+ if (!error) {
+ in_suspend = 1;
+ error = swsusp_suspend();
+ }
+ enable_nonboot_cpus();
+ Resume_devices:
+ device_resume();
+ resume_console();
+ Finish:
+ mutex_unlock(&pm_mutex);
+ return error;
+}
+
+static int snapshot_restore(void)
+{
+ int error;
+
+ mutex_lock(&pm_mutex);
+ pm_prepare_console();
+ suspend_console();
+ error = device_suspend(PMSG_PRETHAW);
+ if (error)
+ goto Resume_devices;
+
+ error = disable_nonboot_cpus();
+ if (!error)
+ error = swsusp_resume();
+
+ enable_nonboot_cpus();
+ Resume_devices:
+ device_resume();
+ resume_console();
+ pm_restore_console();
+ mutex_unlock(&pm_mutex);
+ return error;
+}
+
static int snapshot_ioctl(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
@@ -145,14 +198,9 @@ static int snapshot_ioctl(struct inode *
if (data->frozen)
break;
mutex_lock(&pm_mutex);
- error = disable_nonboot_cpus();
- if (!error) {
- error = freeze_processes();
- if (error) {
- thaw_processes();
- enable_nonboot_cpus();
- error = -EBUSY;
- }
+ if (freeze_processes()) {
+ thaw_processes();
+ error = -EBUSY;
}
mutex_unlock(&pm_mutex);
if (!error)
@@ -164,7 +212,6 @@ static int snapshot_ioctl(struct inode *
break;
mutex_lock(&pm_mutex);
thaw_processes();
- enable_nonboot_cpus();
mutex_unlock(&pm_mutex);
data->frozen = 0;
break;
@@ -174,20 +221,7 @@ static int snapshot_ioctl(struct inode *
error = -EPERM;
break;
}
- mutex_lock(&pm_mutex);
- /* Free memory before shutting down devices. */
- error = swsusp_shrink_memory();
- if (!error) {
- suspend_console();
- error = device_suspend(PMSG_FREEZE);
- if (!error) {
- in_suspend = 1;
- error = swsusp_suspend();
- device_resume();
- }
- resume_console();
- }
- mutex_unlock(&pm_mutex);
+ error = snapshot_suspend();
if (!error)
error = put_user(in_suspend, (unsigned int __user *)arg);
if (!error)
@@ -201,17 +235,7 @@ static int snapshot_ioctl(struct inode *
error = -EPERM;
break;
}
- mutex_lock(&pm_mutex);
- pm_prepare_console();
- suspend_console();
- error = device_suspend(PMSG_PRETHAW);
- if (!error) {
- error = swsusp_resume();
- device_resume();
- }
- resume_console();
- pm_restore_console();
- mutex_unlock(&pm_mutex);
+ error = snapshot_restore();
break;