Re: [PATCH] mm: Do not start/end writeback for pages stored in zswap

[Usama Arif]

On 11/06/2024 10:53, Chengming Zhou wrote:
> On 2024/6/10 22:30, Usama Arif wrote:
> > start/end writeback combination incorrectly increments NR_WRITTEN
> > counter, eventhough the pages aren't written to disk. Pages successfully
> > stored in zswap should just unlock folio and return from writepage.
> >
> > Signed-off-by: Usama Arif <usamaarif642@xxxxxxxxx>
> Looks good to me, thanks.
>
> Reviewed-by: Chengming Zhou <chengming.zhou@xxxxxxxxx>


Fororgot to add:

Suggested-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>

> > ---
> >   mm/page_io.c | 2 --
> >   1 file changed, 2 deletions(-)
> >
> > diff --git a/mm/page_io.c b/mm/page_io.c
> > index a360857cf75d..501784d79977 100644
> > --- a/mm/page_io.c
> > +++ b/mm/page_io.c
> > @@ -196,9 +196,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
> >   		return ret;
> >   	}
> >   	if (zswap_store(folio)) {
> > -		folio_start_writeback(folio);
> >   		folio_unlock(folio);
> > -		folio_end_writeback(folio);
> >   		return 0;
> >   	}
> >   	if (!mem_cgroup_zswap_writeback_enabled(folio_memcg(folio))) {