[RC][PATCH] PM: Remove code duplication between main.c and user.c

Rafael J. Wysocki
2007-06-22T14:50:56Z

From: Rafael J. Wysocki <rjw@sisk.pl>

The SNAPSHOT_S2RAM ioctl code is outdated and it should not duplicate the
suspend code in kernel/power/main.c. Fix that.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
---
kernel/power/main.c | 79 +++++++++++++++++++++++++++++----------------------
kernel/power/power.h | 3 +
kernel/power/user.c | 38 +++---------------------
3 files changed, 53 insertions(+), 67 deletions(-)

Index: linux-2.6.22-rc5/kernel/power/main.c
===================================================================
--- linux-2.6.22-rc5.orig/kernel/power/main.c 2007-06-20 23:17:01.000000000 +0200
+++ linux-2.6.22-rc5/kernel/power/main.c 2007-06-21 23:09:56.000000000 +0200
@@ -71,11 +71,9 @@ static inline void pm_finish(suspend_sta
* suspend_prepare - Do prep work before entering low-power state.
* @state: State we're entering.
*
- * This is common code that is called for each state that we're
- * entering. Allocate a console, stop all processes, then make sure
- * the platform can enter the requested state.
+ * This is common code that is called for each state that we're entering.
+ * Run suspend notifiers, allocate a console and stop all processes.
*/
-
static int suspend_prepare(suspend_state_t state)
{
int error;
@@ -95,38 +93,18 @@ static int suspend_prepare(suspend_state
goto Thaw;
}

- if ((free_pages = global_page_state(NR_FREE_PAGES))
- < FREE_PAGE_NUMBER) {
+ free_pages = global_page_state(NR_FREE_PAGES);
+ if (free_pages < FREE_PAGE_NUMBER) {
pr_debug("PM: free some memory\n");
shrink_all_memory(FREE_PAGE_NUMBER - free_pages);
if (nr_free_pages() < FREE_PAGE_NUMBER) {
error = -ENOMEM;
printk(KERN_ERR "PM: No enough memory\n");
- goto Thaw;
}
}
-
- suspend_console();
- error = device_suspend(PMSG_SUSPEND);
- if (error) {
- printk(KERN_ERR "Some devices failed to suspend\n");
- goto Resume_console;
- }
- if (pm_ops->prepare) {
- if ((error = pm_ops->prepare(state)))
- goto Resume_devices;
- }
-
- error = disable_nonboot_cpus();
if (!error)
return 0;

- enable_nonboot_cpus();
- pm_finish(state);
- Resume_devices:
- device_resume();
- Resume_console:
- resume_console();
Thaw:
thaw_processes();
pm_restore_console();
@@ -147,6 +125,12 @@ void __attribute__ ((weak)) arch_suspend
local_irq_enable();
}

+/**
+ * suspend_enter - enter the desired system sleep state.
+ * @state: state to enter
+ *
+ * This function should be called after devices have been suspended.
+ */
int suspend_enter(suspend_state_t state)
{
int error = 0;
@@ -166,6 +150,41 @@ int suspend_enter(suspend_state_t state)
return error;
}

+/**
+ * suspend_devices_and_enter - suspend devices and enter the desired system sleep
+ * state.
+ * @state: state to enter
+ */
+int suspend_devices_and_enter(suspend_state_t state)
+{
+ int error;
+
+ if (!pm_ops)
+ return -ENOSYS;
+
+ suspend_console();
+ error = device_suspend(PMSG_SUSPEND);
+ if (error) {
+ printk(KERN_ERR "Some devices failed to suspend\n");
+ goto Resume_console;
+ }
+ if (pm_ops->prepare) {
+ error = pm_ops->prepare(state);
+ if (error)
+ goto Resume_devices;
+ }
+ error = disable_nonboot_cpus();
+ if (!error)
+ suspend_enter(state);
+
+ enable_nonboot_cpus();
+ pm_finish(state);
+ Resume_devices:
+ device_resume();
+ Resume_console:
+ resume_console();
+ return error;
+}

/**
* suspend_finish - Do final work before exiting suspend sequence.
@@ -174,13 +193,8 @@ int suspend_enter(suspend_state_t state)
* Call platform code to clean up, restart processes, and free the
* console that we've allocated. This is not called for suspend-to-disk.
*/
-
static void suspend_finish(suspend_state_t state)
{
- enable_nonboot_cpus();
- pm_finish(state);
- device_resume();
- resume_console();
thaw_processes();
pm_restore_console();
pm_notifier_call_chain(PM_POST_SUSPEND);
@@ -215,7 +229,6 @@ static inline int valid_state(suspend_st
* Then, do the setup for suspend, enter the state, and cleaup (after
* we've woken up).
*/
-
static int enter_state(suspend_state_t state)
{
int error;
@@ -230,7 +243,7 @@ static int enter_state(suspend_state_t s
goto Unlock;

pr_debug("PM: Entering %s sleep\n", pm_states[state]);
- error = suspend_enter(state);
+ error = suspend_devices_and_enter(state);

pr_debug("PM: Finishing wakeup.\n");
suspend_finish(state);
Index: linux-2.6.22-rc5/kernel/power/power.h
===================================================================
--- linux-2.6.22-rc5.orig/kernel/power/power.h 2007-06-20 23:16:46.000000000 +0200
+++ linux-2.6.22-rc5/kernel/power/power.h 2007-06-21 23:10:10.000000000 +0200
@@ -170,7 +170,6 @@ extern int swsusp_resume(void);
extern int swsusp_read(unsigned int *flags_p);
extern int swsusp_write(unsigned int flags);
extern void swsusp_close(void);
-extern int suspend_enter(suspend_state_t state);

struct timeval;
/* kernel/power/swsusp.c */
@@ -178,6 +177,8 @@ extern void swsusp_show_speed(struct tim
unsigned int, char *);

/* kernel/power/main.c */
+extern int suspend_enter(suspend_state_t state);
+extern int suspend_devices_and_enter(suspend_state_t state);
extern struct blocking_notifier_head pm_chain_head;

static inline int pm_notifier_call_chain(unsigned long val)
Index: linux-2.6.22-rc5/kernel/power/user.c
===================================================================
--- linux-2.6.22-rc5.orig/kernel/power/user.c 2007-06-20 23:16:46.000000000 +0200
+++ linux-2.6.22-rc5/kernel/power/user.c 2007-06-21 23:29:10.000000000 +0200
@@ -255,47 +255,19 @@ static int snapshot_ioctl(struct inode *
break;

case SNAPSHOT_S2RAM:
- if (!pm_ops) {
- error = -ENOSYS;
- break;
- }
-
if (!data->frozen) {
error = -EPERM;
break;
}
-
if (!mutex_trylock(&pm_mutex)) {
error = -EBUSY;
break;
}
-
- if (pm_ops->prepare) {
- error = pm_ops->prepare(PM_SUSPEND_MEM);
- if (error)
- goto OutS3;
- }
-
- /* Put devices to sleep */
- suspend_console();
- error = device_suspend(PMSG_SUSPEND);
- if (error) {
- printk(KERN_ERR "Failed to suspend some devices.\n");
- } else {
- error = disable_nonboot_cpus();
- if (!error) {
- /* Enter S3, system is already frozen */
- suspend_enter(PM_SUSPEND_MEM);
- enable_nonboot_cpus();
- }
- /* Wake up devices */
- device_resume();
- }
- resume_console();
- if (pm_ops->finish)
- pm_ops->finish(PM_SUSPEND_MEM);
-
- OutS3:
+ /*
+ * 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;