Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

Pull the v3.5 RCU tree from Paul E. McKenney:

 1)	A set of improvements and fixes to the RCU_FAST_NO_HZ feature
	(with more on the way for 3.6).  Posted to LKML:
	https://lkml.org/lkml/2012/4/23/324 (commits 1-3 and 5),
	https://lkml.org/lkml/2012/4/16/611 (commit 4),
	https://lkml.org/lkml/2012/4/30/390 (commit 6), and
	https://lkml.org/lkml/2012/5/4/410 (commit 7, combined with
	the other commits for the convenience of the tester).

 2)	Changes to make rcu_barrier() avoid disrupting execution of CPUs
	that have no RCU callbacks.  Posted to LKML:
	https://lkml.org/lkml/2012/4/23/322.

 3)	A couple of commits that improve the efficiency of the interaction
	between preemptible RCU and the scheduler, these two being all
	that survived an abortive attempt to allow preemptible RCU's
	__rcu_read_lock() to be inlined.  The full set was posted to
	LKML at https://lkml.org/lkml/2012/4/14/143, and the first and
	third patches of that set remain.

 4)	Lai Jiangshan's algorithmic implementation of SRCU, which includes
	call_srcu() and srcu_barrier().  A major feature of this new
	implementation is that synchronize_srcu() no longer disturbs
	the execution of other CPUs.  This work is based on earlier
	implementations by Peter Zijlstra and Paul E. McKenney.  Posted to
	LKML: https://lkml.org/lkml/2012/2/22/82.

 5)	A number of miscellaneous bug fixes and improvements which were
	posted to LKML at: https://lkml.org/lkml/2012/4/23/353 with
	subsequent updates posted to LKML.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/list_debug.c b/lib/list_debug.c
index 982b850d4e7a..3810b481f940 100644
--- a/lib/list_debug.c
+++ b/lib/list_debug.c
@@ -10,6 +10,7 @@
 #include <linux/list.h>
 #include <linux/bug.h>
 #include <linux/kernel.h>
+#include <linux/rculist.h>
 
 /*
  * Insert a new entry between two known consecutive entries.
@@ -75,3 +76,24 @@ void list_del(struct list_head *entry)
 	entry->prev = LIST_POISON2;
 }
 EXPORT_SYMBOL(list_del);
+
+/*
+ * RCU variants.
+ */
+void __list_add_rcu(struct list_head *new,
+		    struct list_head *prev, struct list_head *next)
+{
+	WARN(next->prev != prev,
+		"list_add_rcu corruption. next->prev should be "
+		"prev (%p), but was %p. (next=%p).\n",
+		prev, next->prev, next);
+	WARN(prev->next != next,
+		"list_add_rcu corruption. prev->next should be "
+		"next (%p), but was %p. (prev=%p).\n",
+		next, prev->next, prev);
+	new->next = next;
+	new->prev = prev;
+	rcu_assign_pointer(list_next_rcu(prev), new);
+	next->prev = new;
+}
+EXPORT_SYMBOL(__list_add_rcu);