On (08/11/17 09:10), Yisheng Xie wrote:
> The compr_data_size is a stat for compressed size of pages stored, which
> should add comp_len when we compresse a page.
>
> Meanwhile fix typos in comment:
> * ZRAM_SAME means page consists the same element not the entirely zero page
> * read_from_bdev_async() return 1 to avoid call page_endio() in zram_rw_page()
>
> Signed-off-by: Yisheng Xie <xieyishe...@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhat...@gmail.com>
> ---
> drivers/block/zram/zram_drv.c | 3 ++-
> drivers/block/zram/zram_drv.h | 2 +-
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
> index e27daca..b2b75b1 100644
> --- a/drivers/block/zram/zram_drv.c
> +++ b/drivers/block/zram/zram_drv.c
> @@ -455,7 +455,7 @@ void zram_page_end_io(struct bio *bio)
> }
>
> /*
> - * Returns 0 if the submission is successful.
> + * Returns 1 if the submission is successful.
> */
> static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec,
> unsigned long entry, struct bio *parent)
ok.
> @@ -1073,6 +1073,7 @@ static int __zram_bvec_write(struct zram *zram, struct
> bio_vec *bvec,
> } else {
> zram_set_handle(zram, index, handle);
> zram_set_obj_size(zram, index, comp_len);
> + atomic64_add(comp_len, &zram->stats.compr_data_size);
hm. looks like nothing increments ->compr_data_size as of now... we only
decrement it. so it's possible to have something like
# cat /sys/block/zram0/mm_stat
163594240 18446744073709549720 80388096 0 80388096 15927 0
oops... good catch.
> }
> zram_slot_unlock(zram, index);
>
> diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
> index 5573dc2..31762db 100644
> --- a/drivers/block/zram/zram_drv.h
> +++ b/drivers/block/zram/zram_drv.h
> @@ -60,7 +60,7 @@
>
> /* Flags for zram pages (table[page_no].value) */
> enum zram_pageflags {
> - /* Page consists entirely of zeros */
> + /* Page consists the same element */
> ZRAM_SAME = ZRAM_FLAG_SHIFT,
> ZRAM_ACCESS, /* page is now accessed */
> ZRAM_WB, /* page is stored on backing_device */
ok.
-ss
