1 files changed, 17 insertions, 11 deletions

diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 061550de77bc..f9ebe1c82060 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -65,7 +65,8 @@ static struct kmem_cache *radix_tree_node_cachep;
  */
 struct radix_tree_preload {
         int nr;
-        struct radix_tree_node *nodes[RADIX_TREE_PRELOAD_SIZE];
+        /* nodes->private_data points to next preallocated node */
+        struct radix_tree_node *nodes;
 };
 static DEFINE_PER_CPU(struct radix_tree_preload, radix_tree_preloads) = { 0, };
 
@@ -197,8 +198,9 @@ radix_tree_node_alloc(struct radix_tree_root *root)
                  */
                 rtp = this_cpu_ptr(&radix_tree_preloads);
                 if (rtp->nr) {
-                        ret = rtp->nodes[rtp->nr - 1];
-                        rtp->nodes[rtp->nr - 1] = NULL;
+                        ret = rtp->nodes;
+                        rtp->nodes = ret->private_data;
+                        ret->private_data = NULL;
                         rtp->nr--;
                 }
                 /*
@@ -257,17 +259,20 @@ static int __radix_tree_preload(gfp_t gfp_mask)
 
         preempt_disable();
         rtp = this_cpu_ptr(&radix_tree_preloads);
-        while (rtp->nr < ARRAY_SIZE(rtp->nodes)) {
+        while (rtp->nr < RADIX_TREE_PRELOAD_SIZE) {
                 preempt_enable();
                 node = kmem_cache_alloc(radix_tree_node_cachep, gfp_mask);
                 if (node == NULL)
                         goto out;
                 preempt_disable();
                 rtp = this_cpu_ptr(&radix_tree_preloads);
-                if (rtp->nr < ARRAY_SIZE(rtp->nodes))
-                        rtp->nodes[rtp->nr++] = node;
-                else
+                if (rtp->nr < RADIX_TREE_PRELOAD_SIZE) {
+                        node->private_data = rtp->nodes;
+                        rtp->nodes = node;
+                        rtp->nr++;
+                } else {
                         kmem_cache_free(radix_tree_node_cachep, node);
+                }
         }
         ret = 0;
 out:
@@ -1463,15 +1468,16 @@ static int radix_tree_callback(struct notifier_block *nfb,
 {
        int cpu = (long)hcpu;
        struct radix_tree_preload *rtp;
+       struct radix_tree_node *node;
 
        /* Free per-cpu pool of perloaded nodes */
        if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
                rtp = &per_cpu(radix_tree_preloads, cpu);
                while (rtp->nr) {
-                       kmem_cache_free(radix_tree_node_cachep,
-                                       rtp->nodes[rtp->nr-1]);
-                       rtp->nodes[rtp->nr-1] = NULL;
-                       rtp->nr--;
+                        node = rtp->nodes;
+                        rtp->nodes = node->private_data;
+                        kmem_cache_free(radix_tree_node_cachep, node);
+                        rtp->nr--;
                }
        }
        return NOTIFY_OK;