+/*
+ * smp_processor_id(): get the current CPU ID.
+ *
+ * if DEBUG_PREEMPT is enabled the we check whether it is
+ * used in a preemption-safe way. (smp_processor_id() is safe
+ * if it's used in a preemption-off critical section, or in
+ * a thread that is bound to the current CPU.)
+ *
+ * NOTE: raw_smp_processor_id() is for internal use only
+ * (smp_processor_id() is the preferred variant), but in rare
+ * instances it might also be used to turn off false positives
+ * (i.e. smp_processor_id() use that the debugging code reports but
+ * which use for some reason is legal). Don't use this to hack around
+ * the warning message, as your code might not work under PREEMPT.
+ */
+#ifdef CONFIG_DEBUG_PREEMPT
+ extern unsigned int debug_smp_processor_id(void);
+# define smp_processor_id() debug_smp_processor_id()
+#else
+# define smp_processor_id() raw_smp_processor_id()
+#endif
+