srcu: Use rnp->lock wrappers to replace explicit memory barriers
This commit uses TREE RCU's rnp->lock wrappers to replace a few explicit
memory barriers. This change also has the advantage of making SRCU's
memory-ordering properties be implemented in roughly the same way as they
are in Tree RCU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
index 24e949b..42973f7 100644
--- a/include/linux/srcutree.h
+++ b/include/linux/srcutree.h
@@ -40,7 +40,7 @@ struct srcu_data {
unsigned long srcu_unlock_count[2]; /* Unlocks per CPU. */
/* Update-side state. */
- spinlock_t lock ____cacheline_internodealigned_in_smp;
+ raw_spinlock_t __private lock ____cacheline_internodealigned_in_smp;
struct rcu_segcblist srcu_cblist; /* List of callbacks.*/
unsigned long srcu_gp_seq_needed; /* Furthest future GP needed. */
unsigned long srcu_gp_seq_needed_exp; /* Furthest future exp GP. */
@@ -58,7 +58,7 @@ struct srcu_data {
* Node in SRCU combining tree, similar in function to rcu_data.
*/
struct srcu_node {
- spinlock_t lock;
+ raw_spinlock_t __private lock;
unsigned long srcu_have_cbs[4]; /* GP seq for children */
/* having CBs, but only */
/* is > ->srcu_gq_seq. */
@@ -78,7 +78,7 @@ struct srcu_struct {
struct srcu_node *level[RCU_NUM_LVLS + 1];
/* First node at each level. */
struct mutex srcu_cb_mutex; /* Serialize CB preparation. */
- spinlock_t gp_lock; /* protect ->srcu_cblist */
+ raw_spinlock_t __private lock; /* Protect counters */
struct mutex srcu_gp_mutex; /* Serialize GP work. */
unsigned int srcu_idx; /* Current rdr array element. */
unsigned long srcu_gp_seq; /* Grace-period seq #. */
@@ -109,7 +109,7 @@ void process_srcu(struct work_struct *work);
#define __SRCU_STRUCT_INIT(name) \
{ \
.sda = &name##_srcu_data, \
- .gp_lock = __SPIN_LOCK_UNLOCKED(name.gp_lock), \
+ .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
.srcu_gp_seq_needed = 0 - 1, \
__SRCU_DEP_MAP_INIT(name) \
}