* [PATCH] driver: zram: fix wrong counting on pages_store
@ 2021-07-20 6:47 Huangzhaoyang
2021-07-25 1:19 ` [Resend PATCH] " Zhaoyang Huang
2021-07-26 1:27 ` [PATCH] " Sergey Senozhatsky
0 siblings, 2 replies; 6+ messages in thread
From: Huangzhaoyang @ 2021-07-20 6:47 UTC (permalink / raw)
To: Minchan Kim, Zhaoyang Huang, linux-mm, linux-kernel, Nitin Gupta,
Sergey Senozhatsky
From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
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@unisoc.com>
---
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);
spin_lock(&zram->wb_limit_lock);
if (zram->wb_limit_enable && zram->bd_wb_limit > 0)
zram->bd_wb_limit -= 1UL << (PAGE_SHIFT - 12);
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [Resend PATCH] driver: zram: fix wrong counting on pages_store
2021-07-20 6:47 [PATCH] driver: zram: fix wrong counting on pages_store Huangzhaoyang
@ 2021-07-25 1:19 ` Zhaoyang Huang
2021-07-26 1:27 ` [PATCH] " Sergey Senozhatsky
1 sibling, 0 replies; 6+ messages in thread
From: Zhaoyang Huang @ 2021-07-25 1:19 UTC (permalink / raw)
To: Minchan Kim, Zhaoyang Huang, open list:MEMORY MANAGEMENT, LKML,
Nitin Gupta, Sergey Senozhatsky
Subject: [PATCH] driver: zram: fix wrong counting on pages_store
Date: Tue, 20 Jul 2021 14:47:38 +0800
Message-Id: <1626763658-27748-1-git-send-email-huangzhaoyang@gmail.com>
X-Mailer: git-send-email 1.7.9.5
From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
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@unisoc.com>
---
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);
spin_lock(&zram->wb_limit_lock);
if (zram->wb_limit_enable && zram->bd_wb_limit > 0)
zram->bd_wb_limit -= 1UL << (PAGE_SHIFT - 12);
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] driver: zram: fix wrong counting on pages_store
2021-07-20 6:47 [PATCH] driver: zram: fix wrong counting on pages_store Huangzhaoyang
2021-07-25 1:19 ` [Resend PATCH] " Zhaoyang Huang
@ 2021-07-26 1:27 ` Sergey Senozhatsky
2021-07-26 17:53 ` Minchan Kim
1 sibling, 1 reply; 6+ messages in thread
From: Sergey Senozhatsky @ 2021-07-26 1:27 UTC (permalink / raw)
To: Minchan Kim, Huangzhaoyang
Cc: Zhaoyang Huang, linux-mm, linux-kernel, Nitin Gupta, Sergey Senozhatsky
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@unisoc.com>
> ---
> 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?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] driver: zram: fix wrong counting on pages_store
2021-07-26 1:27 ` [PATCH] " Sergey Senozhatsky
@ 2021-07-26 17:53 ` Minchan Kim
2021-07-27 1:32 ` Zhaoyang Huang
0 siblings, 1 reply; 6+ messages in thread
From: Minchan Kim @ 2021-07-26 17:53 UTC (permalink / raw)
To: Sergey Senozhatsky
Cc: Huangzhaoyang, Zhaoyang Huang, linux-mm, linux-kernel, Nitin Gupta
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@unisoc.com>
> > ---
> > 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.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] driver: zram: fix wrong counting on pages_store
2021-07-26 17:53 ` Minchan Kim
@ 2021-07-27 1:32 ` Zhaoyang Huang
2021-07-27 5:45 ` Zhaoyang Huang
0 siblings, 1 reply; 6+ messages in thread
From: Zhaoyang Huang @ 2021-07-27 1:32 UTC (permalink / raw)
To: Minchan Kim
Cc: Sergey Senozhatsky, Zhaoyang Huang, open list:MEMORY MANAGEMENT,
LKML, Nitin Gupta
On Tue, Jul 27, 2021 at 1:53 AM Minchan Kim <minchan@kernel.org> 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@unisoc.com>
> > > ---
> > > 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.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] driver: zram: fix wrong counting on pages_store
2021-07-27 1:32 ` Zhaoyang Huang
@ 2021-07-27 5:45 ` Zhaoyang Huang
0 siblings, 0 replies; 6+ messages in thread
From: Zhaoyang Huang @ 2021-07-27 5:45 UTC (permalink / raw)
To: Minchan Kim
Cc: Sergey Senozhatsky, Zhaoyang Huang, open list:MEMORY MANAGEMENT,
LKML, Nitin Gupta
On Tue, Jul 27, 2021 at 9:32 AM Zhaoyang Huang <huangzhaoyang@gmail.com> wrote:
>
> On Tue, Jul 27, 2021 at 1:53 AM Minchan Kim <minchan@kernel.org> 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@unisoc.com>
> > > > ---
> > > > 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.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-07-27 5:45 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2021-07-20 6:47 [PATCH] driver: zram: fix wrong counting on pages_store Huangzhaoyang
2021-07-25 1:19 ` [Resend PATCH] " Zhaoyang Huang
2021-07-26 1:27 ` [PATCH] " Sergey Senozhatsky
2021-07-26 17:53 ` Minchan Kim
2021-07-27 1:32 ` Zhaoyang Huang
2021-07-27 5:45 ` Zhaoyang Huang
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