Merge branch 'core/rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core/rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (23 commits)
  rcu classic: update qlen when cpu offline
  rcu: make rcutorture even more vicious: invoke RCU readers from irq handlers (timers)
  rcu: make quiescent rcutorture less power-hungry
  rcu, rcutorture: make quiescent rcutorture less power-hungry
  rcu: make rcutorture more vicious: reinstate boot-time testing
  rcu: make rcutorture more vicious: add stutter feature
  rcutorture: WARN_ON_ONCE(1) when detecting an error
  rcu: remove unused field struct rcu_data::rcu_tasklet
  Revert "prohibit rcutorture from being compiled into the kernel"
  rcu: fix nf_conntrack_helper.c build bug
  rculist.h: fix include in net/netfilter/nf_conntrack_netlink.c
  rcu: remove duplicated include in kernel/rcupreempt.c
  rcu: remove duplicated include in kernel/rcupreempt_trace.c
  RCU, rculist.h: fix list iterators
  rcu: fix rcu_try_flip_waitack_needed() to prevent grace-period stall
  rculist.h: use the rcu API
  rcu: split list.h and move rcu-protected lists into rculist.h
  sched: 1Q08 RCU doc update, add call_rcu_sched()
  rcu: add call_rcu_sched() and friends to rcutorture
  rcu: add rcu_barrier_sched() and rcu_barrier_bh()
  ...

1 files changed, 24 insertions, 2 deletions

diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index d42dbec06083..e8b4039cfb2f 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -40,6 +40,7 @@
 #include <linux/cpumask.h>
 #include <linux/seqlock.h>
 #include <linux/lockdep.h>
+#include <linux/completion.h>
 
 /**
  * struct rcu_head - callback structure for use with RCU
@@ -168,6 +169,27 @@ struct rcu_head {
                 (p) = (v); \
         })
 
+/* Infrastructure to implement the synchronize_() primitives. */
+
+struct rcu_synchronize {
+        struct rcu_head head;
+        struct completion completion;
+};
+
+extern void wakeme_after_rcu(struct rcu_head  *head);
+
+#define synchronize_rcu_xxx(name, func) \
+void name(void) \
+{ \
+        struct rcu_synchronize rcu; \
+        \
+        init_completion(&rcu.completion); \
+        /* Will wake me after RCU finished. */ \
+        func(&rcu.head, wakeme_after_rcu); \
+        /* Wait for it. */ \
+        wait_for_completion(&rcu.completion); \
+}
+
 /**
  * synchronize_sched - block until all CPUs have exited any non-preemptive
  * kernel code sequences.
@@ -224,8 +246,8 @@ extern void call_rcu_bh(struct rcu_head *head,
 /* Exported common interfaces */
 extern void synchronize_rcu(void);
 extern void rcu_barrier(void);
-extern long rcu_batches_completed(void);
-extern long rcu_batches_completed_bh(void);
+extern void rcu_barrier_bh(void);
+extern void rcu_barrier_sched(void);
 
 /* Internal to kernel */
 extern void rcu_init(void);