[PATCH] swsusp: Untangle thaw_processes

[linux-2.6-block.git] / kernel / power / process.c

diff --git a/kernel/power/process.c b/kernel/power/process.c
index 72e72d2c61e6e412106c2e58733087b9ba16ac81..fd0ebb942f5097495e493b79527da5b7c87f74d4 100644 (file)
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -13,12 +13,15 @@
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
+#include <linux/freezer.h>
 
 /* 
  * Timeout for stopping processes
  */
 #define TIMEOUT        (20 * HZ)
 
+#define FREEZER_KERNEL_THREADS 0
+#define FREEZER_USER_SPACE 1
 
 static inline int freezeable(struct task_struct * p)
 {
@@ -39,7 +42,6 @@ void refrigerator(void)
        long save;
        save = current->state;
        pr_debug("%s entered refrigerator\n", current->comm);
-       printk("=");
 
        frozen_process(current);
        spin_lock_irq(&current->sighand->siglock);
@@ -79,6 +81,11 @@ static void cancel_freezing(struct task_struct *p)
        }
 }
 
+static inline int is_user_space(struct task_struct *p)
+{
+       return p->mm && !(p->flags & PF_BORROWED_MM);
+}
+
 /* 0 = success, else # of processes that we failed to stop */
 int freeze_processes(void)
 {
@@ -86,7 +93,7 @@ int freeze_processes(void)
        unsigned long start_time;
        struct task_struct *g, *p;
 
-       printk( "Stopping tasks: " );
+       printk("Stopping tasks... ");
        start_time = jiffies;
        user_frozen = 0;
        do {
@@ -97,14 +104,15 @@ int freeze_processes(void)
                                continue;
                        if (frozen(p))
                                continue;
-                       if (p->state == TASK_TRACED && frozen(p->parent)) {
+                       if (p->state == TASK_TRACED &&
+                           (frozen(p->parent) ||
+                            p->parent->state == TASK_STOPPED)) {
                                cancel_freezing(p);
                                continue;
                        }
-                       if (p->mm && !(p->flags & PF_BORROWED_MM)) {
-                               /* The task is a user-space one.
-                                * Freeze it unless there's a vfork completion
-                                * pending
+                       if (is_user_space(p)) {
+                               /* Freeze the task unless there is a vfork
+                                * completion pending
                                 */
                                if (!p->vfork_done)
                                        freeze_process(p);
@@ -134,41 +142,51 @@ int freeze_processes(void)
         * but it cleans up leftover PF_FREEZE requests.
         */
        if (todo) {
-               printk( "\n" );
-               printk(KERN_ERR " stopping tasks timed out "
+               printk("\n");
+               printk(KERN_ERR "Stopping tasks timed out "
                        "after %d seconds (%d tasks remaining):\n",
                        TIMEOUT / HZ, todo);
                read_lock(&tasklist_lock);
                do_each_thread(g, p) {
                        if (freezeable(p) && !frozen(p))
-                               printk(KERN_ERR "  %s\n", p->comm);
+                               printk(KERN_ERR " %s\n", p->comm);
                        cancel_freezing(p);
                } while_each_thread(g, p);
                read_unlock(&tasklist_lock);
                return todo;
        }
 
-       printk( "|\n" );
+       printk("done.\n");
        BUG_ON(in_atomic());
        return 0;
 }
 
-void thaw_processes(void)
+static void thaw_tasks(int thaw_user_space)
 {
        struct task_struct *g, *p;
 
-       printk( "Restarting tasks..." );
        read_lock(&tasklist_lock);
        do_each_thread(g, p) {
                if (!freezeable(p))
                        continue;
+
+               if (is_user_space(p) == !thaw_user_space)
+                       continue;
+
                if (!thaw_process(p))
-                       printk(KERN_INFO " Strange, %s not stopped\n", p->comm );
+                       printk(KERN_WARNING " Strange, %s not stopped\n",
+                               p->comm );
        } while_each_thread(g, p);
-
        read_unlock(&tasklist_lock);
+}
+
+void thaw_processes(void)
+{
+       printk("Restarting tasks ... ");
+       thaw_tasks(FREEZER_KERNEL_THREADS);
+       thaw_tasks(FREEZER_USER_SPACE);
        schedule();
-       printk( " done\n" );
+       printk("done.\n");
 }
 
 EXPORT_SYMBOL(refrigerator);