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-rw-r--r--include/linux/radix-tree.h1
-rw-r--r--lib/radix-tree.c99
-rw-r--r--mm/shmem.c26
-rw-r--r--tools/testing/radix-tree/main.c8
-rw-r--r--tools/testing/radix-tree/test.c22
-rw-r--r--tools/testing/radix-tree/test.h2
6 files changed, 53 insertions, 105 deletions
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
index 289d007d487b..a13d3f7c6c65 100644
--- a/include/linux/radix-tree.h
+++ b/include/linux/radix-tree.h
@@ -296,7 +296,6 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
unsigned long nr_to_tag,
unsigned int fromtag, unsigned int totag);
int radix_tree_tagged(struct radix_tree_root *root, unsigned int tag);
-unsigned long radix_tree_locate_item(struct radix_tree_root *root, void *item);
static inline void radix_tree_preload_end(void)
{
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 0a7ac0fb4a65..5bdf1bdbca00 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -1579,105 +1579,6 @@ radix_tree_gang_lookup_tag_slot(struct radix_tree_root *root, void ***results,
}
EXPORT_SYMBOL(radix_tree_gang_lookup_tag_slot);
-#if defined(CONFIG_SHMEM) && defined(CONFIG_SWAP)
-#include <linux/sched.h> /* for cond_resched() */
-
-struct locate_info {
- unsigned long found_index;
- bool stop;
-};
-
-/*
- * This linear search is at present only useful to shmem_unuse_inode().
- */
-static unsigned long __locate(struct radix_tree_node *slot, void *item,
- unsigned long index, struct locate_info *info)
-{
- unsigned long i;
-
- do {
- unsigned int shift = slot->shift;
-
- for (i = (index >> shift) & RADIX_TREE_MAP_MASK;
- i < RADIX_TREE_MAP_SIZE;
- i++, index += (1UL << shift)) {
- struct radix_tree_node *node =
- rcu_dereference_raw(slot->slots[i]);
- if (node == RADIX_TREE_RETRY)
- goto out;
- if (!radix_tree_is_internal_node(node)) {
- if (node == item) {
- info->found_index = index;
- info->stop = true;
- goto out;
- }
- continue;
- }
- node = entry_to_node(node);
- if (is_sibling_entry(slot, node))
- continue;
- slot = node;
- break;
- }
- } while (i < RADIX_TREE_MAP_SIZE);
-
-out:
- if ((index == 0) && (i == RADIX_TREE_MAP_SIZE))
- info->stop = true;
- return index;
-}
-
-/**
- * radix_tree_locate_item - search through radix tree for item
- * @root: radix tree root
- * @item: item to be found
- *
- * Returns index where item was found, or -1 if not found.
- * Caller must hold no lock (since this time-consuming function needs
- * to be preemptible), and must check afterwards if item is still there.
- */
-unsigned long radix_tree_locate_item(struct radix_tree_root *root, void *item)
-{
- struct radix_tree_node *node;
- unsigned long max_index;
- unsigned long cur_index = 0;
- struct locate_info info = {
- .found_index = -1,
- .stop = false,
- };
-
- do {
- rcu_read_lock();
- node = rcu_dereference_raw(root->rnode);
- if (!radix_tree_is_internal_node(node)) {
- rcu_read_unlock();
- if (node == item)
- info.found_index = 0;
- break;
- }
-
- node = entry_to_node(node);
-
- max_index = node_maxindex(node);
- if (cur_index > max_index) {
- rcu_read_unlock();
- break;
- }
-
- cur_index = __locate(node, item, cur_index, &info);
- rcu_read_unlock();
- cond_resched();
- } while (!info.stop && cur_index <= max_index);
-
- return info.found_index;
-}
-#else
-unsigned long radix_tree_locate_item(struct radix_tree_root *root, void *item)
-{
- return -1;
-}
-#endif /* CONFIG_SHMEM && CONFIG_SWAP */
-
/**
* __radix_tree_delete_node - try to free node after clearing a slot
* @root: radix tree root
diff --git a/mm/shmem.c b/mm/shmem.c
index be11c6dd414a..54287d443806 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1049,6 +1049,30 @@ static void shmem_evict_inode(struct inode *inode)
clear_inode(inode);
}
+static unsigned long find_swap_entry(struct radix_tree_root *root, void *item)
+{
+ struct radix_tree_iter iter;
+ void **slot;
+ unsigned long found = -1;
+ unsigned int checked = 0;
+
+ rcu_read_lock();
+ radix_tree_for_each_slot(slot, root, &iter, 0) {
+ if (*slot == item) {
+ found = iter.index;
+ break;
+ }
+ checked++;
+ if ((checked % 4096) != 0)
+ continue;
+ slot = radix_tree_iter_resume(slot, &iter);
+ cond_resched_rcu();
+ }
+
+ rcu_read_unlock();
+ return found;
+}
+
/*
* If swap found in inode, free it and move page from swapcache to filecache.
*/
@@ -1062,7 +1086,7 @@ static int shmem_unuse_inode(struct shmem_inode_info *info,
int error = 0;
radswap = swp_to_radix_entry(swap);
- index = radix_tree_locate_item(&mapping->page_tree, radswap);
+ index = find_swap_entry(&mapping->page_tree, radswap);
if (index == -1)
return -EAGAIN; /* tell shmem_unuse we found nothing */
diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
index 76d9c95aa487..a028dae8a043 100644
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -239,7 +239,7 @@ static void __locate_check(struct radix_tree_root *tree, unsigned long index,
item_insert_order(tree, index, order);
item = item_lookup(tree, index);
- index2 = radix_tree_locate_item(tree, item);
+ index2 = find_item(tree, item);
if (index != index2) {
printf("index %ld order %d inserted; found %ld\n",
index, order, index2);
@@ -273,17 +273,17 @@ static void locate_check(void)
index += (1UL << order)) {
__locate_check(&tree, index + offset, order);
}
- if (radix_tree_locate_item(&tree, &tree) != -1)
+ if (find_item(&tree, &tree) != -1)
abort();
item_kill_tree(&tree);
}
}
- if (radix_tree_locate_item(&tree, &tree) != -1)
+ if (find_item(&tree, &tree) != -1)
abort();
__locate_check(&tree, -1, 0);
- if (radix_tree_locate_item(&tree, &tree) != -1)
+ if (find_item(&tree, &tree) != -1)
abort();
item_kill_tree(&tree);
}
diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c
index 0de548939a2e..88bf57f7175e 100644
--- a/tools/testing/radix-tree/test.c
+++ b/tools/testing/radix-tree/test.c
@@ -151,6 +151,28 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
assert(nfound == 0);
}
+/* Use the same pattern as find_swap_entry() in mm/shmem.c */
+unsigned long find_item(struct radix_tree_root *root, void *item)
+{
+ struct radix_tree_iter iter;
+ void **slot;
+ unsigned long found = -1;
+ unsigned long checked = 0;
+
+ radix_tree_for_each_slot(slot, root, &iter, 0) {
+ if (*slot == item) {
+ found = iter.index;
+ break;
+ }
+ checked++;
+ if ((checked % 4) != 0)
+ continue;
+ slot = radix_tree_iter_resume(slot, &iter);
+ }
+
+ return found;
+}
+
static int verify_node(struct radix_tree_node *slot, unsigned int tag,
int tagged)
{
diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h
index 617416ec3c5e..3d9d1d30da22 100644
--- a/tools/testing/radix-tree/test.h
+++ b/tools/testing/radix-tree/test.h
@@ -25,6 +25,8 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
unsigned long nr, int chunk);
void item_kill_tree(struct radix_tree_root *root);
+unsigned long find_item(struct radix_tree_root *, void *item);
+
void tag_check(void);
void multiorder_checks(void);
void iteration_test(void);