Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits)
  sched: Fix broken assertion
  sched: Assert task state bits at build time
  sched: Update task_state_arraypwith new states
  sched: Add missing state chars to TASK_STATE_TO_CHAR_STR
  sched: Move TASK_STATE_TO_CHAR_STR near the TASK_state bits
  sched: Teach might_sleep() about preemptible RCU
  sched: Make warning less noisy
  sched: Simplify set_task_cpu()
  sched: Remove the cfs_rq dependency from set_task_cpu()
  sched: Add pre and post wakeup hooks
  sched: Move kthread_bind() back to kthread.c
  sched: Fix select_task_rq() vs hotplug issues
  sched: Fix sched_exec() balancing
  sched: Ensure set_task_cpu() is never called on blocked tasks
  sched: Use TASK_WAKING for fork wakups
  sched: Select_task_rq_fair() must honour SD_LOAD_BALANCE
  sched: Fix task_hot() test order
  sched: Fix set_cpu_active() in cpu_down()
  sched: Mark boot-cpu active before smp_init()
  sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
  ...

1 files changed, 3 insertions, 21 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 291ac58..1c8ddd6 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -209,6 +209,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
 		return -ENOMEM;
 
 	cpu_hotplug_begin();
+	set_cpu_active(cpu, false);
 	err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
 					hcpu, -1, &nr_calls);
 	if (err == NOTIFY_BAD) {
@@ -280,18 +281,6 @@ int __ref cpu_down(unsigned int cpu)
 		goto out;
 	}
 
-	set_cpu_active(cpu, false);
-
-	/*
-	 * Make sure the all cpus did the reschedule and are not
-	 * using stale version of the cpu_active_mask.
-	 * This is not strictly necessary becuase stop_machine()
-	 * that we run down the line already provides the required
-	 * synchronization. But it's really a side effect and we do not
-	 * want to depend on the innards of the stop_machine here.
-	 */
-	synchronize_sched();
-
 	err = _cpu_down(cpu, 0);
 
 out:
@@ -382,19 +371,12 @@ int disable_nonboot_cpus(void)
 		return error;
 	cpu_maps_update_begin();
 	first_cpu = cpumask_first(cpu_online_mask);
-	/* We take down all of the non-boot CPUs in one shot to avoid races
+	/*
+	 * We take down all of the non-boot CPUs in one shot to avoid races
 	 * with the userspace trying to use the CPU hotplug at the same time
 	 */
 	cpumask_clear(frozen_cpus);
 
-	for_each_online_cpu(cpu) {
-		if (cpu == first_cpu)
-			continue;
-		set_cpu_active(cpu, false);
-	}
-
-	synchronize_sched();
-
 	printk("Disabling non-boot CPUs ...\n");
 	for_each_online_cpu(cpu) {
 		if (cpu == first_cpu)