[RFC][PATCH -mm 2/5] swsusp: Change code ordering in disk.c

Rafael J. Wysocki
2006-11-25T21:34:32Z

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

The changes here only affect the built-in swsusp.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/cpu.c | 2
kernel/power/disk.c | 110 ++++++++++++++++++++++++++--------------------------
2 files changed, 58 insertions(+), 54 deletions(-)

Index: linux-2.6.19-rc6-mm1/kernel/cpu.c
===================================================================
--- linux-2.6.19-rc6-mm1.orig/kernel/cpu.c
+++ linux-2.6.19-rc6-mm1/kernel/cpu.c
@@ -318,6 +318,8 @@ void enable_nonboot_cpus(void)
mutex_lock(&cpu_add_remove_lock);
cpu_hotplug_disabled = 0;
mutex_unlock(&cpu_add_remove_lock);
+ if (cpus_empty(frozen_cpus))
+ return;

printk("Enabling non-boot CPUs ...\n");
for_each_cpu_mask(cpu, frozen_cpus) {
Index: linux-2.6.19-rc6-mm1/kernel/power/disk.c
===================================================================
--- linux-2.6.19-rc6-mm1.orig/kernel/power/disk.c
+++ linux-2.6.19-rc6-mm1/kernel/power/disk.c
@@ -89,52 +89,26 @@ static inline void platform_finish(void)
}
}

+static void unprepare_processes(void)
+{
+ thaw_processes();
+ pm_restore_console();
+}
+
static int prepare_processes(void)
{
int error = 0;

pm_prepare_console();
-
- error = disable_nonboot_cpus();
- if (error)
- goto enable_cpus;
-
if (freeze_processes()) {
error = -EBUSY;
- goto thaw;
- }
-
- if (pm_disk_mode == PM_DISK_TESTPROC) {
- printk("swsusp debug: Waiting for 5 seconds.\n");
- mdelay(5000);
- goto thaw;
- }
-
- error = platform_prepare();
- if (error)
- goto thaw;
-
- /* Free memory before shutting down devices. */
- if (!(error = swsusp_shrink_memory()))
+ } else if (pm_disk_mode != PM_DISK_TESTPROC) {
return 0;
-
- platform_finish();
- thaw:
- thaw_processes();
- enable_cpus:
- enable_nonboot_cpus();
- pm_restore_console();
+ }
+ unprepare_processes();
return error;
}

-static void unprepare_processes(void)
-{
- platform_finish();
- thaw_processes();
- enable_nonboot_cpus();
- pm_restore_console();
-}
-
/**
* pm_suspend_disk - The granpappy of hibernation power management.
*
@@ -152,29 +126,45 @@ int pm_suspend_disk(void)
if (error)
return error;

- if (pm_disk_mode == PM_DISK_TESTPROC)
+ if (pm_disk_mode == PM_DISK_TESTPROC) {
+ printk("swsusp debug: Waiting for 5 seconds.\n");
+ mdelay(5000);
+ goto Thaw;
+ }
+ /* Free memory before shutting down devices. */
+ error = swsusp_shrink_memory();
+ if (error)
+ goto Thaw;
+
+ error = platform_prepare();
+ if (error)
goto Thaw;

suspend_console();
error = device_suspend(PMSG_FREEZE);
if (error) {
- resume_console();
- printk("Some devices failed to suspend\n");
- goto Thaw;
+ printk(KERN_ERR "PM: Some devices failed to suspend\n");
+ goto Resume_devices;
}
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Enable_cpus;

if (pm_disk_mode == PM_DISK_TEST) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
- goto Done;
+ goto Enable_cpus;
}

pr_debug("PM: snapshotting memory.\n");
in_suspend = 1;
- if ((error = swsusp_suspend()))
- goto Done;
+ error = swsusp_suspend();
+ if (error)
+ goto Enable_cpus;

if (in_suspend) {
+ enable_nonboot_cpus();
+ platform_finish();
device_resume();
resume_console();
pr_debug("PM: writing image.\n");
@@ -190,7 +180,10 @@ int pm_suspend_disk(void)
}

swsusp_free();
- Done:
+ Enable_cpus:
+ enable_nonboot_cpus();
+ Resume_devices:
+ platform_finish();
device_resume();
resume_console();
Thaw:
@@ -239,41 +232,50 @@ static int software_resume(void)

pr_debug("PM: Checking swsusp image.\n");

- if ((error = swsusp_check()))
+ error = swsusp_check();
+ if (error)
goto Done;

pr_debug("PM: Preparing processes for restore.\n");

- if ((error = prepare_processes())) {
+ error = prepare_processes();
+ if (error) {
swsusp_close();
goto Done;
}

pr_debug("PM: Reading swsusp image.\n");

- if ((error = swsusp_read())) {
+ error = swsusp_read();
+ if (error) {
swsusp_free();
goto Thaw;
}

pr_debug("PM: Preparing devices for restore.\n");

- suspend_console();
- if ((error = device_suspend(PMSG_PRETHAW))) {
- resume_console();
- printk("Some devices failed to suspend\n");
+ error = platform_prepare();
+ if (error) {
swsusp_free();
goto Thaw;
}
+ suspend_console();
+ error = device_suspend(PMSG_PRETHAW);
+ if (error)
+ goto Free;

- mb();
+ error = disable_nonboot_cpus();
+ if (!error)
+ swsusp_resume();

- pr_debug("PM: Restoring saved image.\n");
- swsusp_resume();
- pr_debug("PM: Restore failed, recovering.n");
+ enable_nonboot_cpus();
+ Free:
+ swsusp_free();
+ platform_finish();
device_resume();
resume_console();
Thaw:
+ printk(KERN_ERR "PM: Restore failed, recovering.\n");
unprepare_processes();
Done:
/* For success case, the suspend path will release the lock */