Index: kernel/generic/include/cpu.h
===================================================================
--- kernel/generic/include/cpu.h	(revision 46b305ad06b46ff90c280b198a0339a0ea00df22)
+++ kernel/generic/include/cpu.h	(revision b83c5e408a25b05bd779719d25173f668005f88a)
@@ -74,4 +74,5 @@
 	size_t missed_clock_ticks;
 
+	/** Can only be accessed when interrupts are disabled. */
 	uint64_t current_clock_tick;