^^^^^^^^^^^^
The Kprobe-optimizer doesn't insert the jump instruction immediately;
-rather, it calls synchronize_sched() for safety first, because it's
+rather, it calls synchronize_rcu() for safety first, because it's
possible for a CPU to be interrupted in the middle of executing the
-optimized region [3]_. As you know, synchronize_sched() can ensure
-that all interruptions that were active when synchronize_sched()
+optimized region [3]_. As you know, synchronize_rcu() can ensure
+that all interruptions that were active when synchronize_rcu()
was called are done, but only if CONFIG_PREEMPT=n. So, this version
of kprobe optimization supports only kernels with CONFIG_PREEMPT=n [4]_.