diff options
Diffstat (limited to 'include/linux/radix-tree.h')
| -rw-r--r-- | include/linux/radix-tree.h | 69 |
1 files changed, 60 insertions, 9 deletions
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index e1512a607709..8558d52e1c7b 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -330,8 +330,9 @@ static inline void radix_tree_preload_end(void) * struct radix_tree_iter - radix tree iterator state * * @index: index of current slot - * @next_index: next-to-last index for this chunk + * @next_index: one beyond the last index for this chunk * @tags: bit-mask for tag-iterating + * @shift: shift for the node that holds our slots * * This radix tree iterator works in terms of "chunks" of slots. A chunk is a * subinterval of slots contained within one radix tree leaf node. It is @@ -344,8 +345,20 @@ struct radix_tree_iter { unsigned long index; unsigned long next_index; unsigned long tags; +#ifdef CONFIG_RADIX_TREE_MULTIORDER + unsigned int shift; +#endif }; +static inline unsigned int iter_shift(struct radix_tree_iter *iter) +{ +#ifdef CONFIG_RADIX_TREE_MULTIORDER + return iter->shift; +#else + return 0; +#endif +} + #define RADIX_TREE_ITER_TAG_MASK 0x00FF /* tag index in lower byte */ #define RADIX_TREE_ITER_TAGGED 0x0100 /* lookup tagged slots */ #define RADIX_TREE_ITER_CONTIG 0x0200 /* stop at first hole */ @@ -405,6 +418,12 @@ void **radix_tree_iter_retry(struct radix_tree_iter *iter) return NULL; } +static inline unsigned long +__radix_tree_iter_add(struct radix_tree_iter *iter, unsigned long slots) +{ + return iter->index + (slots << iter_shift(iter)); +} + /** * radix_tree_iter_next - resume iterating when the chunk may be invalid * @iter: iterator state @@ -416,7 +435,7 @@ void **radix_tree_iter_retry(struct radix_tree_iter *iter) static inline __must_check void **radix_tree_iter_next(struct radix_tree_iter *iter) { - iter->next_index = iter->index + 1; + iter->next_index = __radix_tree_iter_add(iter, 1); iter->tags = 0; return NULL; } @@ -430,7 +449,12 @@ void **radix_tree_iter_next(struct radix_tree_iter *iter) static __always_inline long radix_tree_chunk_size(struct radix_tree_iter *iter) { - return iter->next_index - iter->index; + return (iter->next_index - iter->index) >> iter_shift(iter); +} + +static inline void *indirect_to_ptr(void *ptr) +{ + return (void *)((unsigned long)ptr & ~RADIX_TREE_INDIRECT_PTR); } /** @@ -448,24 +472,51 @@ static __always_inline void ** radix_tree_next_slot(void **slot, struct radix_tree_iter *iter, unsigned flags) { if (flags & RADIX_TREE_ITER_TAGGED) { + void *canon = slot; + iter->tags >>= 1; + if (unlikely(!iter->tags)) + return NULL; + while (IS_ENABLED(CONFIG_RADIX_TREE_MULTIORDER) && + radix_tree_is_indirect_ptr(slot[1])) { + if (indirect_to_ptr(slot[1]) == canon) { + iter->tags >>= 1; + iter->index = __radix_tree_iter_add(iter, 1); + slot++; + continue; + } + iter->next_index = __radix_tree_iter_add(iter, 1); + return NULL; + } if (likely(iter->tags & 1ul)) { - iter->index++; + iter->index = __radix_tree_iter_add(iter, 1); return slot + 1; } - if (!(flags & RADIX_TREE_ITER_CONTIG) && likely(iter->tags)) { + if (!(flags & RADIX_TREE_ITER_CONTIG)) { unsigned offset = __ffs(iter->tags); iter->tags >>= offset; - iter->index += offset + 1; + iter->index = __radix_tree_iter_add(iter, offset + 1); return slot + offset + 1; } } else { - long size = radix_tree_chunk_size(iter); + long count = radix_tree_chunk_size(iter); + void *canon = slot; - while (--size > 0) { + while (--count > 0) { slot++; - iter->index++; + iter->index = __radix_tree_iter_add(iter, 1); + + if (IS_ENABLED(CONFIG_RADIX_TREE_MULTIORDER) && + radix_tree_is_indirect_ptr(*slot)) { + if (indirect_to_ptr(*slot) == canon) + continue; + else { + iter->next_index = iter->index; + break; + } + } + if (likely(*slot)) return slot; if (flags & RADIX_TREE_ITER_CONTIG) { |