KVM: MMU: invalidate and flush on spte small->large page size change

[safe/jmp/linux-2.6] / kernel / freezer.c

diff --git a/kernel/freezer.c b/kernel/freezer.c
index cb0931f..bd1d42b 100644 (file)
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -44,12 +44,19 @@ void refrigerator(void)
        recalc_sigpending(); /* We sent fake signal, clean it up */
        spin_unlock_irq(&current->sighand->siglock);
 
+       /* prevent accounting of that task to load */
+       current->flags |= PF_FREEZING;
+
        for (;;) {
                set_current_state(TASK_UNINTERRUPTIBLE);
                if (!frozen(current))
                        break;
                schedule();
        }
+
+       /* Remove the accounting blocker */
+       current->flags &= ~PF_FREEZING;
+
        pr_debug("%s left refrigerator\n", current->comm);
        __set_current_state(save);
 }
@@ -120,3 +127,35 @@ void cancel_freezing(struct task_struct *p)
                spin_unlock_irqrestore(&p->sighand->siglock, flags);
        }
 }
+
+static int __thaw_process(struct task_struct *p)
+{
+       if (frozen(p)) {
+               p->flags &= ~PF_FROZEN;
+               return 1;
+       }
+       clear_freeze_flag(p);
+       return 0;
+}
+
+/*
+ * Wake up a frozen process
+ *
+ * task_lock() is needed to prevent the race with refrigerator() which may
+ * occur if the freezing of tasks fails.  Namely, without the lock, if the
+ * freezing of tasks failed, thaw_tasks() might have run before a task in
+ * refrigerator() could call frozen_process(), in which case the task would be
+ * frozen and no one would thaw it.
+ */
+int thaw_process(struct task_struct *p)
+{
+       task_lock(p);
+       if (__thaw_process(p) == 1) {
+               task_unlock(p);
+               wake_up_process(p);
+               return 1;
+       }
+       task_unlock(p);
+       return 0;
+}
+EXPORT_SYMBOL(thaw_process);