diff mbox series

[RFC,2/7] mm: change PAGEREF_RECLAIM_CLEAN with PAGE_REFRECLAIM

Message ID 20190520035254.57579-3-minchan@kernel.org (mailing list archive)
State New, archived
Headers show
Series introduce memory hinting API for external process | expand

Commit Message

Minchan Kim May 20, 2019, 3:52 a.m. UTC
The local variable references in shrink_page_list is PAGEREF_RECLAIM_CLEAN
as default. It is for preventing to reclaim dirty pages when CMA try to
migrate pages. Strictly speaking, we don't need it because CMA didn't allow
to write out by .may_writepage = 0 in reclaim_clean_pages_from_list.

Moreover, it has a problem to prevent anonymous pages's swap out even
though force_reclaim = true in shrink_page_list on upcoming patch.
So this patch makes references's default value to PAGEREF_RECLAIM and
rename force_reclaim with skip_reference_check to make it more clear.

This is a preparatory work for next patch.

Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 mm/vmscan.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Johannes Weiner May 20, 2019, 4:50 p.m. UTC | #1
On Mon, May 20, 2019 at 12:52:49PM +0900, Minchan Kim wrote:
> The local variable references in shrink_page_list is PAGEREF_RECLAIM_CLEAN
> as default. It is for preventing to reclaim dirty pages when CMA try to
> migrate pages. Strictly speaking, we don't need it because CMA didn't allow
> to write out by .may_writepage = 0 in reclaim_clean_pages_from_list.
>
> Moreover, it has a problem to prevent anonymous pages's swap out even
> though force_reclaim = true in shrink_page_list on upcoming patch.
> So this patch makes references's default value to PAGEREF_RECLAIM and
> rename force_reclaim with skip_reference_check to make it more clear.
> 
> This is a preparatory work for next patch.
> 
> Signed-off-by: Minchan Kim <minchan@kernel.org>

Looks good to me, just one nit below.

Acked-by: Johannes Weiner <hannes@cmpxchg.org>

> ---
>  mm/vmscan.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index d9c3e873eca6..a28e5d17b495 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -1102,7 +1102,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
>  				      struct scan_control *sc,
>  				      enum ttu_flags ttu_flags,
>  				      struct reclaim_stat *stat,
> -				      bool force_reclaim)
> +				      bool skip_reference_check)

"ignore_references" would be better IMO
Minchan Kim May 20, 2019, 10:57 p.m. UTC | #2
On Mon, May 20, 2019 at 12:50:13PM -0400, Johannes Weiner wrote:
> On Mon, May 20, 2019 at 12:52:49PM +0900, Minchan Kim wrote:
> > The local variable references in shrink_page_list is PAGEREF_RECLAIM_CLEAN
> > as default. It is for preventing to reclaim dirty pages when CMA try to
> > migrate pages. Strictly speaking, we don't need it because CMA didn't allow
> > to write out by .may_writepage = 0 in reclaim_clean_pages_from_list.
> >
> > Moreover, it has a problem to prevent anonymous pages's swap out even
> > though force_reclaim = true in shrink_page_list on upcoming patch.
> > So this patch makes references's default value to PAGEREF_RECLAIM and
> > rename force_reclaim with skip_reference_check to make it more clear.
> > 
> > This is a preparatory work for next patch.
> > 
> > Signed-off-by: Minchan Kim <minchan@kernel.org>
> 
> Looks good to me, just one nit below.
> 
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Thanks, Johannes.

> 
> > ---
> >  mm/vmscan.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/mm/vmscan.c b/mm/vmscan.c
> > index d9c3e873eca6..a28e5d17b495 100644
> > --- a/mm/vmscan.c
> > +++ b/mm/vmscan.c
> > @@ -1102,7 +1102,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
> >  				      struct scan_control *sc,
> >  				      enum ttu_flags ttu_flags,
> >  				      struct reclaim_stat *stat,
> > -				      bool force_reclaim)
> > +				      bool skip_reference_check)
> 
> "ignore_references" would be better IMO

Sure.
diff mbox series

Patch

diff --git a/mm/vmscan.c b/mm/vmscan.c
index d9c3e873eca6..a28e5d17b495 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1102,7 +1102,7 @@  static unsigned long shrink_page_list(struct list_head *page_list,
 				      struct scan_control *sc,
 				      enum ttu_flags ttu_flags,
 				      struct reclaim_stat *stat,
-				      bool force_reclaim)
+				      bool skip_reference_check)
 {
 	LIST_HEAD(ret_pages);
 	LIST_HEAD(free_pages);
@@ -1116,7 +1116,7 @@  static unsigned long shrink_page_list(struct list_head *page_list,
 		struct address_space *mapping;
 		struct page *page;
 		int may_enter_fs;
-		enum page_references references = PAGEREF_RECLAIM_CLEAN;
+		enum page_references references = PAGEREF_RECLAIM;
 		bool dirty, writeback;
 
 		cond_resched();
@@ -1248,7 +1248,7 @@  static unsigned long shrink_page_list(struct list_head *page_list,
 			}
 		}
 
-		if (!force_reclaim)
+		if (!skip_reference_check)
 			references = page_check_references(page, sc);
 
 		switch (references) {