On Tue, Jul 27, 2021 at 9:32 AM Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> wrote: > > On Tue, Jul 27, 2021 at 1:53 AM Minchan Kim <minchan@xxxxxxxxxx> wrote: > > > > On Mon, Jul 26, 2021 at 10:27:40AM +0900, Sergey Senozhatsky wrote: > > > On (21/07/20 14:47), Huangzhaoyang wrote: > > > > It makes the statistic confused when counting pages_store in during writeback. > > > > pages_store should just reflect the swapped pages on ZRAM, while bd_writes be > > > > responsible for writeback things. > > > > > > > > Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> > > > > --- > > > > drivers/block/zram/zram_drv.c | 1 - > > > > 1 file changed, 1 deletion(-) > > > > > > > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > > > > index cf8deec..6bdaa9d 100644 > > > > --- a/drivers/block/zram/zram_drv.c > > > > +++ b/drivers/block/zram/zram_drv.c > > > > @@ -765,7 +765,6 @@ static ssize_t writeback_store(struct device *dev, > > > > zram_set_flag(zram, index, ZRAM_WB); > > > > zram_set_element(zram, index, blk_idx); > > > > blk_idx = 0; > > > > - atomic64_inc(&zram->stats.pages_stored); > > > > > > Yeah, I think we don't need it here. > > > > > > Minchan, what do you think? > > > > What pages_stored currently represents is orig_data_size from mm_stat > > > > ================ ============================================================= > > orig_data_size uncompressed size of data stored in this disk. > > Unit: bytes > > > > Thus, if we don't increase it after zram_free_page, it loses what's > > the original data size which would be important to calculate > > compression ratio along with compr_data_size. > zram_free_page?? What the commit try to fix is pages_stored being > increased incorrectly in writeback_store, which will lead to wrong > statistic on orig size of ZRAM. OK, if I understand right, I think what you mean is the page count corresponding to SWAP should be still available even if it is written back to the backing dev.So we need to increase page_stored again after zram_free_page free it.
