[PATCH] suspend/resume SMP support

Using CPU hotplug to support suspend/resume SMP.  Both S3 and S4 use
disable/enable_nonboot_cpus API.  The S4 part is based on Pavel's original S4
SMP patch.

Signed-off-by: Li Shaohua<shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 18 insertions, 17 deletions

diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 02b6764034dc..fb8de63c2919 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -117,8 +117,8 @@ static void finish(void)
 {
         device_resume();
         platform_finish();
-        enable_nonboot_cpus();
         thaw_processes();
+        enable_nonboot_cpus();
         pm_restore_console();
 }
 
@@ -131,28 +131,35 @@ static int prepare_processes(void)
 
         sys_sync();
 
+        disable_nonboot_cpus();
+
         if (freeze_processes()) {
                 error = -EBUSY;
-                return error;
+                goto thaw;
         }
 
         if (pm_disk_mode == PM_DISK_PLATFORM) {
                 if (pm_ops && pm_ops->prepare) {
                         if ((error = pm_ops->prepare(PM_SUSPEND_DISK)))
-                                return error;
+                                goto thaw;
                 }
         }
 
         /* Free memory before shutting down devices. */
         free_some_memory();
-
         return 0;
+thaw:
+        thaw_processes();
+        enable_nonboot_cpus();
+        pm_restore_console();
+        return error;
 }
 
 static void unprepare_processes(void)
 {
-        enable_nonboot_cpus();
+        platform_finish();
         thaw_processes();
+        enable_nonboot_cpus();
         pm_restore_console();
 }
 
@@ -160,15 +167,9 @@ static int prepare_devices(void)
 {
         int error;
 
-        disable_nonboot_cpus();
-        if ((error = device_suspend(PMSG_FREEZE))) {
+        if ((error = device_suspend(PMSG_FREEZE)))
                 printk("Some devices failed to suspend\n");
-                platform_finish();
-                enable_nonboot_cpus();
-                return error;
-        }
-
-        return 0;
+        return error;
 }
 
 /**
@@ -185,9 +186,9 @@ int pm_suspend_disk(void)
         int error;
 
         error = prepare_processes();
-        if (!error) {
-                error = prepare_devices();
-        }
+        if (error)
+                return error;
+        error = prepare_devices();
 
         if (error) {
                 unprepare_processes();
@@ -250,7 +251,7 @@ static int software_resume(void)
 
         if ((error = prepare_processes())) {
                 swsusp_close();
-                goto Cleanup;
+                goto Done;
         }
 
         pr_debug("PM: Reading swsusp image.\n");