Index: kernel/doc/synchronization
===================================================================
--- kernel/doc/synchronization	(revision b10e6e31d0f332626f6e576a32b9d212b7751e01)
+++ kernel/doc/synchronization	(revision d0ee0de27d6c6cdab1b0395b52d3f7e8f02c6dd3)
@@ -5,4 +5,14 @@
                                  | spinlock_t |
                                  +------------+
+                                       |
+                                       +------------------------------+
+                                                                      |
+                      INTERRUPTS-DISABLED SPINNING LOCKS              |
+       irq_spinlock_lock, irq_spinlock_trylock, irq_spinlock_unlock   |
+                               +----------------+                     |
+                               | irq_spinlock_t |<--------------------+
+                               +----------------+
+
+
 
                                    WAIT QUEUES
@@ -10,6 +20,6 @@
                                    +---------+
                                    | waitq_t |
-			           +---------+
-				  /           \
+                                   +---------+
+                                  /           \
                SEMAPHORES        /             \  CONDITION VARIABLES
  semaphore_down_timeout, semaphore_up    condvar_wait_timeout, condvar_signal
@@ -18,12 +28,12 @@
             +--------------+                         +-----------+
                    |                                       ^
-		   |                                       |
+                   |                                       |
                    |                                +------+
-                   V                               /           
+                   V                               /
                 MUTEXES                           / READERS/WRITERS LOCKS
     mutex_lock_timeout, mutex_unlock   rwlock_reader/writer_lock_timeout, rwlock_unlock
               +---------+                       /        +----------+
-	      | mutex_t |------------------------------->| rwlock_t |
-	      +---------+                     /          +----------+
-	           |                         /
-		   +------------------------+
+              | mutex_t |------------------------------->| rwlock_t |
+              +---------+                     /          +----------+
+                   |                         /
+                   +------------------------+