This commit moves the rcu_init_levelspread() function from
kernel/rcu/tree.c to kernel/rcu/rcu.h so that SRCU can access it. This is
another step towards enabling SRCU to create its own combining tree.
This commit is code-movement only, give or take knock-on adjustments.
Signed-off-by: Paul E. McKenney <paul...@linux.vnet.ibm.com>
---
include/linux/rcu_node_tree.h | 3 ---
kernel/rcu/rcu.h | 36 ++++++++++++++++++++++++++++++++++++
kernel/rcu/srcu.c | 1 +
kernel/rcu/tree.c | 25 -------------------------
kernel/rcu/tree_trace.c | 1 +
5 files changed, 38 insertions(+), 28 deletions(-)
diff --git a/include/linux/rcu_node_tree.h b/include/linux/rcu_node_tree.h
index b7eb97096b1c..4b766b61e1a0 100644
--- a/include/linux/rcu_node_tree.h
+++ b/include/linux/rcu_node_tree.h
@@ -96,7 +96,4 @@
# error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
#endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */
-extern int rcu_num_lvls;
-extern int rcu_num_nodes;
-
#endif /* __LINUX_RCU_NODE_TREE_H */
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index a943b42a9cf7..87326479b39a 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -190,4 +190,40 @@ void rcu_test_sync_prims(void);
*/
extern void resched_cpu(int cpu);
+#if defined(SRCU) || !defined(TINY_RCU)
+
+#include <linux/rcu_node_tree.h>
+
+extern int rcu_num_lvls;
+extern int rcu_num_nodes;
+static bool rcu_fanout_exact;
+static int rcu_fanout_leaf;
+
+/*
+ * Compute the per-level fanout, either using the exact fanout specified
+ * or balancing the tree, depending on the rcu_fanout_exact boot parameter.
+ */
+static inline void rcu_init_levelspread(int *levelspread, const int *levelcnt)
+{
+ int i;
+
+ if (rcu_fanout_exact) {
+ levelspread[rcu_num_lvls - 1] = rcu_fanout_leaf;
+ for (i = rcu_num_lvls - 2; i >= 0; i--)
+ levelspread[i] = RCU_FANOUT;
+ } else {
+ int ccur;
+ int cprv;
+
+ cprv = nr_cpu_ids;
+ for (i = rcu_num_lvls - 1; i >= 0; i--) {
+ ccur = levelcnt[i];
+ levelspread[i] = (cprv + ccur - 1) / ccur;
+ cprv = ccur;
+ }
+ }
+}
+
+#endif /* #if defined(SRCU) || !defined(TINY_RCU) */
+
#endif /* __LINUX_RCU_H */
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index 56fd30862122..0b511de7ca4d 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -36,6 +36,7 @@
#include <linux/delay.h>
#include <linux/srcu.h>
+#include <linux/rcu_node_tree.h>
#include "rcu.h"
static int init_srcu_struct_fields(struct srcu_struct *sp)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 844a030c1960..df3527744af8 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3952,31 +3952,6 @@ void rcu_scheduler_starting(void)
}
/*
- * Compute the per-level fanout, either using the exact fanout specified
- * or balancing the tree, depending on the rcu_fanout_exact boot parameter.
- */
-static void __init rcu_init_levelspread(int *levelspread, const int *levelcnt)
-{
- int i;
-
- if (rcu_fanout_exact) {
- levelspread[rcu_num_lvls - 1] = rcu_fanout_leaf;
- for (i = rcu_num_lvls - 2; i >= 0; i--)
- levelspread[i] = RCU_FANOUT;
- } else {
- int ccur;
- int cprv;
-
- cprv = nr_cpu_ids;
- for (i = rcu_num_lvls - 1; i >= 0; i--) {
- ccur = levelcnt[i];
- levelspread[i] = (cprv + ccur - 1) / ccur;
- cprv = ccur;
- }
- }
-}
-
-/*
* Helper function for rcu_init() that initializes one rcu_state structure.
*/
static void __init rcu_init_one(struct rcu_state *rsp)
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 066c64071a7b..30c5bf89ee58 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -45,6 +45,7 @@
#define RCU_TREE_NONCORE
#include "tree.h"
+#include "rcu.h"
static int r_open(struct inode *inode, struct file *file,
const struct seq_operations *op)
--
2.5.2
