f2fs: write dirty meta pages collectively

This patch enhances writing dirty meta pages collectively in background.
During the file data writes, it'd better avoid to write small dirty meta pages
frequently.
So let's give a chance to collect a number of dirty meta pages for a while.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index f8c074961e0a96126caf33ac08c29a4212033e2b..2fc3b6beaeb8b7ddeb8ddb48edd7f3445b8be75e 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -107,18 +107,19 @@ static int f2fs_write_meta_pages(struct address_space *mapping,
                                struct writeback_control *wbc)
 {
        struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
-       struct block_device *bdev = sbi->sb->s_bdev;
+       int nrpages = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
        long written;
 
        if (wbc->for_kupdate)
                return 0;
 
-       if (get_pages(sbi, F2FS_DIRTY_META) == 0)
+       /* collect a number of dirty meta pages and write together */
+       if (get_pages(sbi, F2FS_DIRTY_META) < nrpages)
                return 0;
 
        /* if mounting is failed, skip writing node pages */
        mutex_lock(&sbi->cp_mutex);
-       written = sync_meta_pages(sbi, META, bio_get_nr_vecs(bdev));
+       written = sync_meta_pages(sbi, META, nrpages);
        mutex_unlock(&sbi->cp_mutex);
        wbc->nr_to_write -= written;
        return 0;