diff mbox series

[v2,2/5] mm: change PAGEREF_RECLAIM_CLEAN with PAGE_REFRECLAIM

Message ID 20190610111252.239156-3-minchan@kernel.org (mailing list archive)
State New, archived
Headers show
Series Introduce MADV_COLD and MADV_PAGEOUT | expand

Commit Message

Minchan Kim June 10, 2019, 11:12 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 ignore_references to make it more clear.

This is a preparatory work for next patch.

* RFCv1
 * use ignore_referecnes as parameter name - hannes

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

Comments

Michal Hocko June 19, 2019, 1:09 p.m. UTC | #1
On Mon 10-06-19 20:12:49, 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 ignore_references to make it more clear.
> 
> This is a preparatory work for next patch.
> 
> * RFCv1
>  * use ignore_referecnes as parameter name - hannes
> 
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
> Signed-off-by: Minchan Kim <minchan@kernel.org>

The code path is quite tricky to follow but the patch looks OK to me.

Acked-by: Michal Hocko <mhocko@suse.com>

> ---
>  mm/vmscan.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 84dcb651d05c..0973a46a0472 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 ignore_references)
>  {
>  	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;
>  		unsigned int nr_pages;
>  
> @@ -1247,7 +1247,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
>  			}
>  		}
>  
> -		if (!force_reclaim)
> +		if (!ignore_references)
>  			references = page_check_references(page, sc);
>  
>  		switch (references) {
> -- 
> 2.22.0.rc2.383.gf4fbbf30c2-goog
diff mbox series

Patch

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 84dcb651d05c..0973a46a0472 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 ignore_references)
 {
 	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;
 		unsigned int nr_pages;
 
@@ -1247,7 +1247,7 @@  static unsigned long shrink_page_list(struct list_head *page_list,
 			}
 		}
 
-		if (!force_reclaim)
+		if (!ignore_references)
 			references = page_check_references(page, sc);
 
 		switch (references) {