If there is no cold page, we don't need to do a loop to flush dirty
data pages.
On /dev/pmem0,
1. dd if=/dev/zero of=/mnt/test/testfile bs=1M count=2048 conv=fsync
 Before : 1.1 GB/s
 After  : 1.2 GB/s
2. dd if=/dev/zero of=/mnt/test/testfile bs=1M count=2048
 Before : 2.2 GB/s
 After  : 2.3 GB/s
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
        int cycled;
        int range_whole = 0;
        int tag;
-       int step = 0;
 
        pagevec_init(&pvec, 0);
-next:
+
        if (wbc->range_cyclic) {
                writeback_index = mapping->writeback_index; /* prev offset */
                index = writeback_index;
                                goto continue_unlock;
                        }
 
-                       if (step == is_cold_data(page))
-                               goto continue_unlock;
-
                        if (PageWriteback(page)) {
                                if (wbc->sync_mode != WB_SYNC_NONE)
                                        f2fs_wait_on_page_writeback(page,
                cond_resched();
        }
 
-       if (step < 1) {
-               step++;
-               goto next;
-       }
-
        if (!cycled && !done) {
                cycled = 1;
                index = 0;