Commit-ID: 83d40bd3bc3ab3d6b5a4a331f7667d627948a099
Gitweb: http://git.kernel.org/tip/83d40bd3bc3ab3d6b5a4a331f7667d627948a099
Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
AuthorDate: Tue, 9 May 2017 13:28:51 -0700
Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
CommitDate: Thu, 8 Jun 2017 18:52:38 -0700
rcu: Move rnp->lock wrappers for SRCU use
This commit moves the now-generic rnp->lock wrapper macros from
kernel/rcu/tree.h to kernel/rcu/rcu.h, thus allowing SRCU to use them.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/rcu.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
kernel/rcu/tree.h | 53 -----------------------------------------------------
2 files changed, 53 insertions(+), 53 deletions(-)
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 6a1e85b..2a75beb8 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -303,6 +303,59 @@ static inline void rcu_init_levelspread(int *levelspread, const int *levelcnt)
cpu <= rnp->grphi; \
cpu = cpumask_next((cpu), cpu_possible_mask))
+/*
+ * Wrappers for the rcu_node::lock acquire and release.
+ *
+ * Because the rcu_nodes form a tree, the tree traversal locking will observe
+ * different lock values, this in turn means that an UNLOCK of one level
+ * followed by a LOCK of another level does not imply a full memory barrier;
+ * and most importantly transitivity is lost.
+ *
+ * In order to restore full ordering between tree levels, augment the regular
+ * lock acquire functions with smp_mb__after_unlock_lock().
+ *
+ * As ->lock of struct rcu_node is a __private field, therefore one should use
+ * these wrappers rather than directly call raw_spin_{lock,unlock}* on ->lock.
+ */
+#define raw_spin_lock_rcu_node(p) \
+do { \
+ raw_spin_lock(&ACCESS_PRIVATE(p, lock)); \
+ smp_mb__after_unlock_lock(); \
+} while (0)
+
+#define raw_spin_unlock_rcu_node(p) raw_spin_unlock(&ACCESS_PRIVATE(p, lock))
+
+#define raw_spin_lock_irq_rcu_node(p) \
+do { \
+ raw_spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \
+ smp_mb__after_unlock_lock(); \
+} while (0)
+
+#define raw_spin_unlock_irq_rcu_node(p) \
+ raw_spin_unlock_irq(&ACCESS_PRIVATE(p, lock))
+
+#define raw_spin_lock_irqsave_rcu_node(rnp, flags) \
+do { \
+ typecheck(unsigned long, flags); \
+ raw_spin_lock_irqsave(&ACCESS_PRIVATE(rnp, lock), flags); \
+ smp_mb__after_unlock_lock(); \
+} while (0)
+
+#define raw_spin_unlock_irqrestore_rcu_node(rnp, flags) \
+do { \
+ typecheck(unsigned long, flags); \
+ raw_spin_unlock_irqrestore(&ACCESS_PRIVATE(rnp, lock), flags); \
+} while (0)
+
+#define raw_spin_trylock_rcu_node(p) \
+({ \
+ bool ___locked = raw_spin_trylock(&ACCESS_PRIVATE(p, lock)); \
+ \
+ if (___locked) \
+ smp_mb__after_unlock_lock(); \
+ ___locked; \
+})
+
#endif /* #if defined(SRCU) || !defined(TINY_RCU) */
#ifdef CONFIG_TINY_RCU
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index a7f63f1..baa0bac 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -565,56 +565,3 @@ static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll)
#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
}
#endif /* #ifdef CONFIG_RCU_TRACE */
-
-/*
- * Wrappers for the rcu_node::lock acquire and release.
- *
- * Because the rcu_nodes form a tree, the tree traversal locking will observe
- * different lock values, this in turn means that an UNLOCK of one level
- * followed by a LOCK of another level does not imply a full memory barrier;
- * and most importantly transitivity is lost.
- *
- * In order to restore full ordering between tree levels, augment the regular
- * lock acquire functions with smp_mb__after_unlock_lock().
- *
- * As ->lock of struct rcu_node is a __private field, therefore one should use
- * these wrappers rather than directly call raw_spin_{lock,unlock}* on ->lock.
- */
-#define raw_spin_lock_rcu_node(p) \
-do { \
- raw_spin_lock(&ACCESS_PRIVATE(p, lock)); \
- smp_mb__after_unlock_lock(); \
-} while (0)
-
-#define raw_spin_unlock_rcu_node(p) raw_spin_unlock(&ACCESS_PRIVATE(p, lock))
-
-#define raw_spin_lock_irq_rcu_node(p) \
-do { \
- raw_spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \
- smp_mb__after_unlock_lock(); \
-} while (0)
-
-#define raw_spin_unlock_irq_rcu_node(p) \
- raw_spin_unlock_irq(&ACCESS_PRIVATE(p, lock))
-
-#define raw_spin_lock_irqsave_rcu_node(rnp, flags) \
-do { \
- typecheck(unsigned long, flags); \
- raw_spin_lock_irqsave(&ACCESS_PRIVATE(rnp, lock), flags); \
- smp_mb__after_unlock_lock(); \
-} while (0)
-
-#define raw_spin_unlock_irqrestore_rcu_node(rnp, flags) \
-do { \
- typecheck(unsigned long, flags); \
- raw_spin_unlock_irqrestore(&ACCESS_PRIVATE(rnp, lock), flags); \
-} while (0)
-
-#define raw_spin_trylock_rcu_node(p) \
-({ \
- bool ___locked = raw_spin_trylock(&ACCESS_PRIVATE(p, lock)); \
- \
- if (___locked) \
- smp_mb__after_unlock_lock(); \
- ___locked; \
-})
--
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