orig_data_size counted the same_pages by commit 51f9f82c ("zram:
count same page write as page_stored"), so let's fix it.
Signed-off-by: Yue Hu <zbestahu@163.com>
Link: https://lore.kernel.org/r/20200206111031.9524-1-zbestahu@gmail.comSigned-off-by: Jonathan Corbet <corbet@lwn.net>