From: Nikolay Borisov Date: Wed, 27 Jun 2018 13:38:22 +0000 (+0300) Subject: btrfs: Refactor loop in btrfs_release_extent_buffer_page X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=d64766fdf9cd172f8416d898cc9d5219ed933b96;p=openwrt%2Fstaging%2Fblogic.git btrfs: Refactor loop in btrfs_release_extent_buffer_page The purpose of the function is to free all the pages comprising an extent buffer. This can be achieved with a simple for loop rather than the slightly more involved 'do {} while' construct. So rewrite the loop using a 'for' construct. Additionally we can never have an extent_buffer that has 0 pages so remove the check for index == 0. No functional changes. The reversed order used to have a meaning in the past where the first page served as a blocking point for several callers. See eg 4f2de97acee6532b36dd6e99 ("Btrfs: set page->private to the eb"). Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 96039dd56c72..66b5272bbaab 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4647,19 +4647,16 @@ int extent_buffer_under_io(struct extent_buffer *eb) */ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb) { - int index; - struct page *page; + int i; + int num_pages; int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags); BUG_ON(extent_buffer_under_io(eb)); - index = num_extent_pages(eb); - if (index == 0) - return; + num_pages = num_extent_pages(eb); + for (i = 0; i < num_pages; i++) { + struct page *page = eb->pages[i]; - do { - index--; - page = eb->pages[index]; if (!page) continue; if (mapped) @@ -4691,7 +4688,7 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb) /* One for when we allocated the page */ put_page(page); - } while (index != 0); + } } /*