diff options
| -rw-r--r-- | include/linux/radix-tree.h | 16 | ||||
| -rw-r--r-- | mm/shmem.c | 12 |
2 files changed, 19 insertions, 9 deletions
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index b211f145c811..51a97ac8bfbf 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -403,6 +403,22 @@ void **radix_tree_iter_retry(struct radix_tree_iter *iter) } /** + * radix_tree_iter_next - resume iterating when the chunk may be invalid + * @iter: iterator state + * + * If the iterator needs to release then reacquire a lock, the chunk may + * have been invalidated by an insertion or deletion. Call this function + * to continue the iteration from the next index. + */ +static inline __must_check +void **radix_tree_iter_next(struct radix_tree_iter *iter) +{ + iter->next_index = iter->index + 1; + iter->tags = 0; + return NULL; +} + +/** * radix_tree_chunk_size - get current chunk size * * @iter: pointer to radix tree iterator diff --git a/mm/shmem.c b/mm/shmem.c index 91c0dadf48d3..9428c51ab2d6 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -376,7 +376,6 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, rcu_read_lock(); -restart: radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { if (iter.index >= end) break; @@ -393,8 +392,7 @@ restart: if (need_resched()) { cond_resched_rcu(); - start = iter.index + 1; - goto restart; + slot = radix_tree_iter_next(&iter); } } @@ -1944,7 +1942,6 @@ static void shmem_tag_pins(struct address_space *mapping) start = 0; rcu_read_lock(); -restart: radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { page = radix_tree_deref_slot(slot); if (!page || radix_tree_exception(page)) { @@ -1961,8 +1958,7 @@ restart: if (need_resched()) { cond_resched_rcu(); - start = iter.index + 1; - goto restart; + slot = radix_tree_iter_next(&iter); } } rcu_read_unlock(); @@ -1999,7 +1995,6 @@ static int shmem_wait_for_pins(struct address_space *mapping) start = 0; rcu_read_lock(); -restart: radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, start, SHMEM_TAG_PINNED) { @@ -2033,8 +2028,7 @@ restart: continue_resched: if (need_resched()) { cond_resched_rcu(); - start = iter.index + 1; - goto restart; + slot = radix_tree_iter_next(&iter); } } rcu_read_unlock(); |