Re: [PATCH] mm: vmscan: remove unused scan_control parameter from pageout()

[Yang Shi]

On 10/4/19 1:16 AM, Michal Hocko wrote:
> On Fri 04-10-19 01:41:38, Yang Shi wrote:
> > Since lumpy reclaim was removed in v3.5 scan_control is not used by
> > may_write_to_{queue|inode} and pageout() anymore, remove the unused
> > parameter.
> I haven't really checked whether it was the lumpy reclaim removal but it
> is clearly not used these days.

It was removed by commit c53919adc045bf803252e912f23028a68525753d ("mm: 
vmscan: remove lumpy reclaim").

> > Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> > Cc: Michal Hocko <mhocko@xxxxxxxx>
> > Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>
>
> Thanks!
>
> > ---
> >   mm/vmscan.c | 9 ++++-----
> >   1 file changed, 4 insertions(+), 5 deletions(-)
> >
> > diff --git a/mm/vmscan.c b/mm/vmscan.c
> > index e5d52d6..17489b8 100644
> > --- a/mm/vmscan.c
> > +++ b/mm/vmscan.c
> > @@ -774,7 +774,7 @@ static inline int is_page_cache_freeable(struct page *page)
> >   	return page_count(page) - page_has_private(page) == 1 + page_cache_pins;
> >   }
> >   
> > -static int may_write_to_inode(struct inode *inode, struct scan_control *sc)
> > +static int may_write_to_inode(struct inode *inode)
> >   {
> >   	if (current->flags & PF_SWAPWRITE)
> >   		return 1;
> > @@ -822,8 +822,7 @@ static void handle_write_error(struct address_space *mapping,
> >    * pageout is called by shrink_page_list() for each dirty page.
> >    * Calls ->writepage().
> >    */
> > -static pageout_t pageout(struct page *page, struct address_space *mapping,
> > -			 struct scan_control *sc)
> > +static pageout_t pageout(struct page *page, struct address_space *mapping)
> >   {
> >   	/*
> >   	 * If the page is dirty, only perform writeback if that write
> > @@ -859,7 +858,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
> >   	}
> >   	if (mapping->a_ops->writepage == NULL)
> >   		return PAGE_ACTIVATE;
> > -	if (!may_write_to_inode(mapping->host, sc))
> > +	if (!may_write_to_inode(mapping->host))
> >   		return PAGE_KEEP;
> >   
> >   	if (clear_page_dirty_for_io(page)) {
> > @@ -1396,7 +1395,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
> >   			 * starts and then write it out here.
> >   			 */
> >   			try_to_unmap_flush_dirty();
> > -			switch (pageout(page, mapping, sc)) {
> > +			switch (pageout(page, mapping)) {
> >   			case PAGE_KEEP:
> >   				goto keep_locked;
> >   			case PAGE_ACTIVATE:
> > --
> > 1.8.3.1