f2fs: always assume that the device is idle under gc_urgent

This allows more aggressive discards and balancing job to be done
under gc_urgent.
Signed-off-by: NPark Ju Hyung <qkrwngud825@gmail.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/f2fs.h

@@ -2193,6 +2193,9 @@ static inline struct bio *f2fs_bio_alloc(struct f2fs_sb_info *sbi,
 
 static inline bool is_idle(struct f2fs_sb_info *sbi, int type)
 {
+	if (sbi->gc_mode == GC_URGENT)
+		return true;
+
 	if (get_pages(sbi, F2FS_RD_DATA) || get_pages(sbi, F2FS_RD_NODE) ||
 		get_pages(sbi, F2FS_RD_META) || get_pages(sbi, F2FS_WB_DATA) ||
 		get_pages(sbi, F2FS_WB_CP_DATA) ||