very heavy lock, which is equivalent to grabbing every spinlock
(and more). So the "read" side to such a lock is anything which
diables preeempt. */
-#include <linux/config.h>
#include <linux/cpu.h>
#include <asm/system.h>
-#ifdef CONFIG_SMP
+#if defined(CONFIG_STOP_MACHINE) && defined(CONFIG_SMP)
/**
* stop_machine_run: freeze the machine on all CPUs and run this function
* @fn: the function to run