Merge branches 'x86-alternatives-for-linus', 'x86-fpu-for-linus', 'x86-hwmon-for...

[pandora-kernel.git] / kernel / cpu.c

diff --git a/kernel/cpu.c b/kernel/cpu.c
index f6e726f..156cc55 100644 (file)
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -189,7 +189,6 @@ static inline void check_for_tasks(int cpu)
 }
 
 struct take_cpu_down_param {
-       struct task_struct *caller;
        unsigned long mod;
        void *hcpu;
 };
@@ -198,7 +197,6 @@ struct take_cpu_down_param {
 static int __ref take_cpu_down(void *_param)
 {
        struct take_cpu_down_param *param = _param;
-       unsigned int cpu = (unsigned long)param->hcpu;
        int err;
 
        /* Ensure this CPU doesn't handle any more interrupts. */
@@ -208,11 +206,6 @@ static int __ref take_cpu_down(void *_param)
 
        cpu_notify(CPU_DYING | param->mod, param->hcpu);
 
-       if (task_cpu(param->caller) == cpu)
-               move_task_off_dead_cpu(cpu, param->caller);
-       /* Force idle task to run as soon as we yield: it should
-          immediately notice cpu is offline and die quickly. */
-       sched_idle_next();
        return 0;
 }
 
@@ -223,7 +216,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
        void *hcpu = (void *)(long)cpu;
        unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
        struct take_cpu_down_param tcd_param = {
-               .caller = current,
                .mod = mod,
                .hcpu = hcpu,
        };
@@ -253,9 +245,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
        }
        BUG_ON(cpu_online(cpu));
 
-       /* Wait for it to sleep (leaving idle task). */
+       /*
+        * The migration_call() CPU_DYING callback will have removed all
+        * runnable tasks from the cpu, there's only the idle task left now
+        * that the migration thread is done doing the stop_machine thing.
+        *
+        * Wait for the stop thread to go away.
+        */
        while (!idle_cpu(cpu))
-               yield();
+               cpu_relax();
 
        /* This actually kills the CPU. */
        __cpu_die(cpu);
@@ -386,6 +384,14 @@ out:
 #ifdef CONFIG_PM_SLEEP_SMP
 static cpumask_var_t frozen_cpus;
 
+void __weak arch_disable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_disable_nonboot_cpus_end(void)
+{
+}
+
 int disable_nonboot_cpus(void)
 {
        int cpu, first_cpu, error = 0;
@@ -397,6 +403,7 @@ int disable_nonboot_cpus(void)
         * with the userspace trying to use the CPU hotplug at the same time
         */
        cpumask_clear(frozen_cpus);
+       arch_disable_nonboot_cpus_begin();
 
        printk("Disabling non-boot CPUs ...\n");
        for_each_online_cpu(cpu) {
@@ -412,6 +419,8 @@ int disable_nonboot_cpus(void)
                }
        }
 
+       arch_disable_nonboot_cpus_end();
+
        if (!error) {
                BUG_ON(num_online_cpus() > 1);
                /* Make sure the CPUs won't be enabled by someone else */