From: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
Set the 'indirect_ptr' bit on all the pointers to internal nodes, not
just on the root node. This enables the following patches to support
multi-order entries in the radix tree. This patch is split out for ease
of bisection.
Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
---
lib/radix-tree.c | 24 ++++++++++++++++++------
tools/testing/radix-tree/test.c | 5 +++--
2 files changed, 21 insertions(+), 8 deletions(-)
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 7a984ad..422a92a 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -360,9 +360,10 @@ static int radix_tree_extend(struct radix_tree_root *root, unsigned long index)
node->count = 1;
node->parent = NULL;
slot = root->rnode;
- if (newheight > 1) {
+ if (radix_tree_is_indirect_ptr(slot) && newheight > 1) {
slot = indirect_to_ptr(slot);
slot->parent = node;
+ slot = ptr_to_indirect(slot);
}
node->slots[0] = slot;
node = ptr_to_indirect(node);
@@ -418,17 +419,20 @@ int __radix_tree_create(struct radix_tree_root *root, unsigned long index,
slot->path = height;
slot->parent = node;
if (node) {
- rcu_assign_pointer(node->slots[offset], slot);
+ rcu_assign_pointer(node->slots[offset],
+ ptr_to_indirect(slot));
node->count++;
slot->path |= offset << RADIX_TREE_HEIGHT_SHIFT;
} else
- rcu_assign_pointer(root->rnode, ptr_to_indirect(slot));
+ rcu_assign_pointer(root->rnode,
+ ptr_to_indirect(slot));
}
/* Go a level down */
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
node = slot;
slot = node->slots[offset];
+ slot = indirect_to_ptr(slot);
shift -= RADIX_TREE_MAP_SHIFT;
height--;
}
@@ -526,6 +530,7 @@ void *__radix_tree_lookup(struct radix_tree_root *root, unsigned long index,
node = rcu_dereference_raw(*slot);
if (node == NULL)
return NULL;
+ node = indirect_to_ptr(node);
shift -= RADIX_TREE_MAP_SHIFT;
height--;
@@ -612,6 +617,7 @@ void *radix_tree_tag_set(struct radix_tree_root *root,
tag_set(slot, tag, offset);
slot = slot->slots[offset];
BUG_ON(slot == NULL);
+ slot = indirect_to_ptr(slot);
shift -= RADIX_TREE_MAP_SHIFT;
height--;
}
@@ -651,11 +657,12 @@ void *radix_tree_tag_clear(struct radix_tree_root *root,
goto out;
shift = height * RADIX_TREE_MAP_SHIFT;
- slot = indirect_to_ptr(root->rnode);
+ slot = root->rnode;
while (shift) {
if (slot == NULL)
goto out;
+ slot = indirect_to_ptr(slot);
shift -= RADIX_TREE_MAP_SHIFT;
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
@@ -731,6 +738,7 @@ int radix_tree_tag_get(struct radix_tree_root *root,
if (node == NULL)
return 0;
+ node = indirect_to_ptr(node);
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
if (!tag_get(node, tag, offset))
@@ -831,6 +839,7 @@ restart:
node = rcu_dereference_raw(node->slots[offset]);
if (node == NULL)
goto restart;
+ node = indirect_to_ptr(node);
shift -= RADIX_TREE_MAP_SHIFT;
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
}
@@ -932,6 +941,7 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
shift -= RADIX_TREE_MAP_SHIFT;
node = slot;
slot = slot->slots[offset];
+ slot = indirect_to_ptr(slot);
continue;
}
@@ -1181,6 +1191,7 @@ static unsigned long __locate(struct radix_tree_node *slot, void *item,
slot = rcu_dereference_raw(slot->slots[i]);
if (slot == NULL)
goto out;
+ slot = indirect_to_ptr(slot);
}
/* Bottom level: check items */
@@ -1264,7 +1275,8 @@ static inline void radix_tree_shrink(struct radix_tree_root *root)
*/
if (to_free->count != 1)
break;
- if (!to_free->slots[0])
+ slot = to_free->slots[0];
+ if (!slot)
break;
/*
@@ -1274,8 +1286,8 @@ static inline void radix_tree_shrink(struct radix_tree_root *root)
* (to_free->slots[0]), it will be safe to dereference the new
* one (root->rnode) as far as dependent read barriers go.
*/
- slot = to_free->slots[0];
if (root->height > 1) {
+ slot = indirect_to_ptr(slot);
slot->parent = NULL;
slot = ptr_to_indirect(slot);
}
diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c
index c9b0bd7..2bebf34 100644
--- a/tools/testing/radix-tree/test.c
+++ b/tools/testing/radix-tree/test.c
@@ -142,6 +142,8 @@ static int verify_node(struct radix_tree_node *slot, unsigned int tag,
int i;
int j;
+ slot = indirect_to_ptr(slot);
+
/* Verify consistency at this level */
for (i = 0; i < RADIX_TREE_TAG_LONGS; i++) {
if (slot->tags[tag][i]) {
@@ -184,8 +186,7 @@ void verify_tag_consistency(struct radix_tree_root *root, unsigned int tag)
{
if (!root->height)
return;
- verify_node(indirect_to_ptr(root->rnode),
- tag, root->height, !!root_tag_get(root, tag));
+ verify_node(root->rnode, tag, root->height, !!root_tag_get(root, tag));
}
void item_kill_tree(struct radix_tree_root *root)
--
2.7.0.rc3
--
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