From 860f2759d94bf9db637d85d75d074de88af54688 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Fri, 22 Feb 2013 16:35:17 -0800 Subject: [PATCH] mm: shmem: use new radix tree iterator In shmem_find_get_pages_and_swap(), use the faster radix tree iterator construct from commit 78c1d78488a3 ("radix-tree: introduce bit-optimized iterator"). Signed-off-by: Johannes Weiner Acked-by: Hugh Dickins Cc: Konstantin Khlebnikov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/shmem.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 5dd56f6efdbd..7162c58355b1 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -335,19 +335,19 @@ static unsigned shmem_find_get_pages_and_swap(struct address_space *mapping, pgoff_t start, unsigned int nr_pages, struct page **pages, pgoff_t *indices) { - unsigned int i; - unsigned int ret; - unsigned int nr_found; + void **slot; + unsigned int ret = 0; + struct radix_tree_iter iter; + + if (!nr_pages) + return 0; rcu_read_lock(); restart: - nr_found = radix_tree_gang_lookup_slot(&mapping->page_tree, - (void ***)pages, indices, start, nr_pages); - ret = 0; - for (i = 0; i < nr_found; i++) { + radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { struct page *page; repeat: - page = radix_tree_deref_slot((void **)pages[i]); + page = radix_tree_deref_slot(slot); if (unlikely(!page)) continue; if (radix_tree_exception(page)) { @@ -364,17 +364,16 @@ static unsigned shmem_find_get_pages_and_swap(struct address_space *mapping, goto repeat; /* Has the page moved? */ - if (unlikely(page != *((void **)pages[i]))) { + if (unlikely(page != *slot)) { page_cache_release(page); goto repeat; } export: - indices[ret] = indices[i]; + indices[ret] = iter.index; pages[ret] = page; - ret++; + if (++ret == nr_pages) + break; } - if (unlikely(!ret && nr_found)) - goto restart; rcu_read_unlock(); return ret; }