there cannot be any readers who hold references to the data structure,
and these can now be safely reclaimed (e.g., freed or unref'ed).
-Here is a picutre:
+Here is a picture:
thread 1 thread 2 thread 3
------------------- ------------------------ -------------------
and then read from there.
RCU read-side critical sections must use atomic_rcu_read() to
- read data, unless concurrent writes are presented by another
+ read data, unless concurrent writes are prevented by another
synchronization mechanism.
Furthermore, RCU read-side critical sections should traverse the