f2fs_gc
int f2fs_gc(struct f2fs_sb_info *sbi, struct f2fs_gc_control *gc_control);
err = f2fs_gc(sbi, &gc_control);
ret = f2fs_gc(sbi, &gc_control);
ret = f2fs_gc(sbi, &gc_control);
ret = f2fs_gc(sbi, &gc_control);
if (f2fs_gc(sbi, &gc_control)) {
f2fs_gc(sbi, &gc_control);
err = f2fs_gc(sbi, &gc_control);