Index: kernel/generic/src/time/delay.c
===================================================================
--- kernel/generic/src/time/delay.c	(revision d7533c7a0181109196018556b0ffcb2435426ce2)
+++ kernel/generic/src/time/delay.c	(revision 854eddd6711fa7a5783a815c8d140d5414badf49)
@@ -37,4 +37,5 @@
  
 #include <time/delay.h>
+#include <proc/thread.h>
 #include <typedefs.h>
 #include <cpu.h>
@@ -42,9 +43,7 @@
 #include <arch.h>
 
-/** Active delay
+/** Delay the execution for the given number of microseconds (or slightly more).
  *
- * Delay the execution for the given number
- * of microseconds (or slightly more). The delay
- * is implemented as CPU calibrated active loop.
+ * The delay is implemented as active delay loop.
  *
  * @param usec Number of microseconds to sleep.
@@ -52,17 +51,16 @@
 void delay(uint32_t usec)
 {
-	ipl_t ipl;
-	
 	/* 
-	 * The delay loop is calibrated for each and every
-	 * CPU in the system. Therefore it is necessary to
-	 * call interrupts_disable() before calling the
-	 * asm_delay_loop().
+	 * The delay loop is calibrated for each and every CPU in the system.
+	 * If running in a thread context, it is therefore necessary to disable
+	 * thread migration. We want to do this in a lightweight manner.
 	 */
-	ipl = interrupts_disable();
+	if (THREAD)
+		thread_migration_disable();
 	asm_delay_loop(usec * CPU->delay_loop_const);
-	interrupts_restore(ipl);
+	if (THREAD)
+		thread_migration_enable();
 }
 
 /** @}
- */
+*/