From 028a63a6e381d7d109e19db4740085d1b655c539 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 15 Nov 2017 17:34:51 -0800 Subject: [PATCH] f2fs: simplify page iteration loops In several places we want to iterate over all tagged pages in a mapping. However the code was apparently copied from places that iterate only over a limited range and thus it checks for index <= end, optimizes the case where we are coming close to range end which is all pointless when end == ULONG_MAX. So just remove this dead code. [akpm@linux-foundation.org: fix warnings] Link: http://lkml.kernel.org/r/20171009151359.31984-7-jack@suse.cz Signed-off-by: Jan Kara Reviewed-by: Daniel Jordan Reviewed-by: Chao Yu Cc: Jaegeuk Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/f2fs/checkpoint.c | 13 ++++------ fs/f2fs/node.c | 59 +++++++++++++++----------------------------- 2 files changed, 25 insertions(+), 47 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 04fe1df052b2..fb74ec4ed9d2 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -305,9 +305,10 @@ long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type, long nr_to_write, enum iostat_type io_type) { struct address_space *mapping = META_MAPPING(sbi); - pgoff_t index = 0, end = ULONG_MAX, prev = ULONG_MAX; + pgoff_t index = 0, prev = ULONG_MAX; struct pagevec pvec; long nwritten = 0; + int nr_pages; struct writeback_control wbc = { .for_reclaim = 0, }; @@ -317,13 +318,9 @@ long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type, blk_start_plug(&plug); - while (index <= end) { - int i, nr_pages; - nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, - PAGECACHE_TAG_DIRTY, - min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); - if (unlikely(nr_pages == 0)) - break; + while ((nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, + PAGECACHE_TAG_DIRTY, PAGEVEC_SIZE))) { + int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index fca87835a1da..ca020e7d7465 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1277,21 +1277,17 @@ release_page: static struct page *last_fsync_dnode(struct f2fs_sb_info *sbi, nid_t ino) { - pgoff_t index, end; + pgoff_t index; struct pagevec pvec; struct page *last_page = NULL; + int nr_pages; pagevec_init(&pvec, 0); index = 0; - end = ULONG_MAX; - while (index <= end) { - int i, nr_pages; - nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, - PAGECACHE_TAG_DIRTY, - min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); - if (nr_pages == 0) - break; + while ((nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, + PAGECACHE_TAG_DIRTY, PAGEVEC_SIZE))) { + int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; @@ -1425,13 +1421,14 @@ static int f2fs_write_node_page(struct page *page, int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode, struct writeback_control *wbc, bool atomic) { - pgoff_t index, end; + pgoff_t index; pgoff_t last_idx = ULONG_MAX; struct pagevec pvec; int ret = 0; struct page *last_page = NULL; bool marked = false; nid_t ino = inode->i_ino; + int nr_pages; if (atomic) { last_page = last_fsync_dnode(sbi, ino); @@ -1441,15 +1438,10 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode, retry: pagevec_init(&pvec, 0); index = 0; - end = ULONG_MAX; - while (index <= end) { - int i, nr_pages; - nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, - PAGECACHE_TAG_DIRTY, - min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); - if (nr_pages == 0) - break; + while ((nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, + PAGECACHE_TAG_DIRTY, PAGEVEC_SIZE))) { + int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; @@ -1548,25 +1540,21 @@ out: int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc, bool do_balance, enum iostat_type io_type) { - pgoff_t index, end; + pgoff_t index; struct pagevec pvec; int step = 0; int nwritten = 0; int ret = 0; + int nr_pages; pagevec_init(&pvec, 0); next_step: index = 0; - end = ULONG_MAX; - while (index <= end) { - int i, nr_pages; - nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, - PAGECACHE_TAG_DIRTY, - min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); - if (nr_pages == 0) - break; + while ((nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, + PAGECACHE_TAG_DIRTY, PAGEVEC_SIZE))) { + int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; @@ -1655,27 +1643,20 @@ out: int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino) { - pgoff_t index = 0, end = ULONG_MAX; + pgoff_t index = 0; struct pagevec pvec; int ret2, ret = 0; + int nr_pages; pagevec_init(&pvec, 0); - while (index <= end) { - int i, nr_pages; - nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, - PAGECACHE_TAG_WRITEBACK, - min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); - if (nr_pages == 0) - break; + while ((nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, + PAGECACHE_TAG_WRITEBACK, PAGEVEC_SIZE))) { + int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; - /* until radix tree lookup accepts end_index */ - if (unlikely(page->index > end)) - continue; - if (ino && ino_of_node(page) == ino) { f2fs_wait_on_page_writeback(page, NODE, true); if (TestClearPageError(page))