ixj: push BKL into driver and wrap ioctls

[linux-2.6-omap-h63xx.git] / Documentation / RCU / whatisRCU.txt

diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt
index 820fee23696746312693b39fb8c44fa7316b1a70..e04d643a9f57a802e59057165f719f36b5ebf5ab 100644 (file)
--- a/Documentation/RCU/whatisRCU.txt
+++ b/Documentation/RCU/whatisRCU.txt
@@ -1,3 +1,11 @@
+Please note that the "What is RCU?" LWN series is an excellent place
+to start learning about RCU:
+
+1.     What is RCU, Fundamentally?  http://lwn.net/Articles/262464/
+2.     What is RCU? Part 2: Usage   http://lwn.net/Articles/263130/
+3.     RCU part 3: the RCU API      http://lwn.net/Articles/264090/
+
+

 What is RCU?
 
 RCU is a synchronization mechanism that was added to the Linux kernel
 What is RCU?
 
 RCU is a synchronization mechanism that was added to the Linux kernel


@@ -772,24 +780,18 @@ Linux-kernel source code, but it helps to have a full list of the
 APIs, since there does not appear to be a way to categorize them
 in docbook.  Here is the list, by category.
 
 APIs, since there does not appear to be a way to categorize them
 in docbook.  Here is the list, by category.
 

-Markers for RCU read-side critical sections:
-
-       rcu_read_lock
-       rcu_read_unlock
-       rcu_read_lock_bh
-       rcu_read_unlock_bh
-

 RCU pointer/list traversal:
 
        rcu_dereference
 RCU pointer/list traversal:
 
        rcu_dereference

+       list_for_each_entry_rcu
+       hlist_for_each_entry_rcu
+

        list_for_each_rcu               (to be deprecated in favor of
                                         list_for_each_entry_rcu)
        list_for_each_rcu               (to be deprecated in favor of
                                         list_for_each_entry_rcu)

-       list_for_each_entry_rcu

        list_for_each_continue_rcu      (to be deprecated in favor of new
                                         list_for_each_entry_continue_rcu)
        list_for_each_continue_rcu      (to be deprecated in favor of new
                                         list_for_each_entry_continue_rcu)

-       hlist_for_each_entry_rcu

 
 

-RCU pointer update:
+RCU pointer/list update:

 
        rcu_assign_pointer
        list_add_rcu
 
        rcu_assign_pointer
        list_add_rcu


@@ -797,15 +799,36 @@ RCU pointer update:
        list_del_rcu
        list_replace_rcu
        hlist_del_rcu
        list_del_rcu
        list_replace_rcu
        hlist_del_rcu

+       hlist_add_after_rcu
+       hlist_add_before_rcu

        hlist_add_head_rcu
        hlist_add_head_rcu

+       hlist_replace_rcu
+       list_splice_init_rcu()
+
+RCU:   Critical sections       Grace period            Barrier
+
+       rcu_read_lock           synchronize_net         rcu_barrier
+       rcu_read_unlock         synchronize_rcu
+                               call_rcu
+
+
+bh:    Critical sections       Grace period            Barrier
+
+       rcu_read_lock_bh        call_rcu_bh             rcu_barrier_bh
+       rcu_read_unlock_bh
+
+
+sched: Critical sections       Grace period            Barrier
+
+       [preempt_disable]       synchronize_sched       rcu_barrier_sched
+       [and friends]           call_rcu_sched
+
+
+SRCU:  Critical sections       Grace period            Barrier

 
 

-RCU grace period:
+       srcu_read_lock          synchronize_srcu        N/A
+       srcu_read_unlock

 
 

-       synchronize_net
-       synchronize_sched
-       synchronize_rcu
-       call_rcu
-       call_rcu_bh

 
 See the comment headers in the source code (or the docbook generated
 from them) for more information.
 
 See the comment headers in the source code (or the docbook generated
 from them) for more information.