The patch titled Subject: radix-tree: split node->path into offset and height has been added to the -mm tree. Its filename is radix-tree-split-node-path-into-offset-and-height.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/radix-tree-split-node-path-into-offset-and-height.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/radix-tree-split-node-path-into-offset-and-height.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> Subject: radix-tree: split node->path into offset and height Neither piece of information we're storing in node->path can be larger than 64, so store each in its own unsigned char instead of shifting and masking to store them both in an unsigned int. Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> Reviewed-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> Cc: Konstantin Khlebnikov <koct9i@xxxxxxxxx> Cc: Kirill Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/radix-tree.h | 7 +----- lib/radix-tree.c | 38 +++++++++++++++-------------------- 2 files changed, 19 insertions(+), 26 deletions(-) diff -puN include/linux/radix-tree.h~radix-tree-split-node-path-into-offset-and-height include/linux/radix-tree.h --- a/include/linux/radix-tree.h~radix-tree-split-node-path-into-offset-and-height +++ a/include/linux/radix-tree.h @@ -84,16 +84,13 @@ static inline int radix_tree_is_indirect #define RADIX_TREE_MAX_PATH (DIV_ROUND_UP(RADIX_TREE_INDEX_BITS, \ RADIX_TREE_MAP_SHIFT)) -/* Height component in node->path */ -#define RADIX_TREE_HEIGHT_SHIFT (RADIX_TREE_MAX_PATH + 1) -#define RADIX_TREE_HEIGHT_MASK ((1UL << RADIX_TREE_HEIGHT_SHIFT) - 1) - /* Internally used bits of node->count */ #define RADIX_TREE_COUNT_SHIFT (RADIX_TREE_MAP_SHIFT + 1) #define RADIX_TREE_COUNT_MASK ((1UL << RADIX_TREE_COUNT_SHIFT) - 1) struct radix_tree_node { - unsigned int path; /* Offset in parent & height from the bottom */ + unsigned char height; /* From the bottom */ + unsigned char offset; /* Slot offset in parent */ unsigned int count; union { struct { diff -puN lib/radix-tree.c~radix-tree-split-node-path-into-offset-and-height lib/radix-tree.c --- a/lib/radix-tree.c~radix-tree-split-node-path-into-offset-and-height +++ a/lib/radix-tree.c @@ -218,15 +218,15 @@ radix_tree_find_next_bit(const unsigned } #ifndef __KERNEL__ -static void dump_node(struct radix_tree_node *node, unsigned offset, +static void dump_node(struct radix_tree_node *node, unsigned shift, unsigned long index) { unsigned long i; - pr_debug("radix node: %p offset %d tags %lx %lx %lx path %x count %d parent %p\n", - node, offset, + pr_debug("radix node: %p offset %d tags %lx %lx %lx height %d count %d parent %p\n", + node, node->offset, node->tags[0][0], node->tags[1][0], node->tags[2][0], - node->path, node->count, node->parent); + node->height, node->count, node->parent); for (i = 0; i < RADIX_TREE_MAP_SIZE; i++) { unsigned long first = index | (i << shift); @@ -243,7 +243,7 @@ static void dump_node(struct radix_tree_ pr_debug("radix entry %p offset %ld indices %ld-%ld\n", entry, i, first, last); } else { - dump_node(indirect_to_ptr(entry), i, + dump_node(indirect_to_ptr(entry), shift - RADIX_TREE_MAP_SHIFT, first); } } @@ -257,7 +257,7 @@ static void radix_tree_dump(struct radix root->gfp_mask >> __GFP_BITS_SHIFT); if (!radix_tree_is_indirect_ptr(root->rnode)) return; - dump_node(indirect_to_ptr(root->rnode), 0, + dump_node(indirect_to_ptr(root->rnode), (root->height - 1) * RADIX_TREE_MAP_SHIFT, 0); } #endif @@ -421,7 +421,7 @@ static inline unsigned long radix_tree_m static inline unsigned long node_maxindex(struct radix_tree_node *node) { - return radix_tree_maxindex(node->path & RADIX_TREE_HEIGHT_MASK); + return radix_tree_maxindex(node->height); } static unsigned radix_tree_load_root(struct radix_tree_root *root, @@ -434,8 +434,7 @@ static unsigned radix_tree_load_root(str if (likely(radix_tree_is_indirect_ptr(node))) { node = indirect_to_ptr(node); *maxindex = node_maxindex(node); - return (node->path & RADIX_TREE_HEIGHT_MASK) * - RADIX_TREE_MAP_SHIFT; + return node->height * RADIX_TREE_MAP_SHIFT; } *maxindex = 0; @@ -476,9 +475,10 @@ static int radix_tree_extend(struct radi } /* Increase the height. */ - newheight = root->height+1; - BUG_ON(newheight & ~RADIX_TREE_HEIGHT_MASK); - node->path = newheight; + newheight = root->height + 1; + BUG_ON(newheight > BITS_PER_LONG); + node->height = newheight; + node->offset = 0; node->count = 1; node->parent = NULL; slot = root->rnode; @@ -546,13 +546,13 @@ int __radix_tree_create(struct radix_tre slot = radix_tree_node_alloc(root); if (!slot) return -ENOMEM; - slot->path = height; + slot->height = height; + slot->offset = offset; slot->parent = node; if (node) { 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)); @@ -1319,11 +1319,10 @@ struct locate_info { static unsigned long __locate(struct radix_tree_node *slot, void *item, unsigned long index, struct locate_info *info) { - unsigned int shift, height; + unsigned int shift; unsigned long base, i; - height = slot->path & RADIX_TREE_HEIGHT_MASK; - shift = height * RADIX_TREE_MAP_SHIFT; + shift = slot->height * RADIX_TREE_MAP_SHIFT; do { shift -= RADIX_TREE_MAP_SHIFT; @@ -1509,10 +1508,7 @@ bool __radix_tree_delete_node(struct rad parent = node->parent; if (parent) { - unsigned int offset; - - offset = node->path >> RADIX_TREE_HEIGHT_SHIFT; - parent->slots[offset] = NULL; + parent->slots[node->offset] = NULL; parent->count--; } else { root_tag_clear_all(root); _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxxxx are radix-tree-introduce-radix_tree_empty.patch radix-tree-test-suite-fix-build.patch radix-tree-test-suite-add-tests-for-radix_tree_locate_item.patch introduce-config_radix_tree_multiorder.patch radix-tree-add-missing-sibling-entry-functionality.patch radix-tree-fix-sibling-entry-insertion.patch radix-tree-fix-deleting-a-multi-order-entry-through-an-alias.patch radix-tree-remove-restriction-on-multi-order-entries.patch radix-tree-introduce-radix_tree_load_root.patch radix-tree-fix-extending-the-tree-for-multi-order-entries-at-offset-0.patch radix-tree-test-suite-start-adding-multiorder-tests.patch radix-tree-fix-several-shrinking-bugs-with-multiorder-entries.patch radix-tree-rewrite-__radix_tree_lookup.patch radix-tree-fix-multiorder-bug_on-in-radix_tree_insert.patch radix-tree-fix-radix_tree_create-for-sibling-entries.patch radix-tree-rewrite-radix_tree_locate_item.patch radix-tree-fix-radix_tree_range_tag_if_tagged-for-multiorder-entries.patch radix-tree-add-copyright-statements.patch drivers-hwspinlock-use-correct-radix-tree-api.patch radix-tree-miscellaneous-fixes.patch radix-tree-split-node-path-into-offset-and-height.patch radix-tree-replace-node-height-with-node-shift.patch radix-tree-remove-a-use-of-root-height-from-delete_node.patch radix-tree-test-suite-remove-dependencies-on-height.patch radix-tree-remove-root-height.patch radix-tree-rename-indirect_ptr-to-internal_node.patch radix-tree-rename-ptr_to_indirect-to-node_to_entry.patch radix-tree-rename-indirect_to_ptr-to-entry_to_node.patch radix-tree-rename-radix_tree_is_indirect_ptr.patch radix-tree-change-naming-conventions-in-radix_tree_shrink.patch radix-tree-tidy-up-next_chunk.patch radix-tree-tidy-up-range_tag_if_tagged.patch radix-tree-tidy-up-__radix_tree_create.patch radix-tree-introduce-radix_tree_replace_clear_tags.patch radix-tree-make-radix_tree_descend-more-useful.patch radix-tree-free-up-the-bottom-bit-of-exceptional-entries-for-reuse.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html