diff mbox series

[v14,058/138] mm/swap: Add folio_mark_accessed()

Message ID 20210715033704.692967-59-willy@infradead.org (mailing list archive)
State New
Headers show
Series Memory folios | expand

Commit Message

Matthew Wilcox July 15, 2021, 3:35 a.m. UTC
Convert mark_page_accessed() to folio_mark_accessed().  It already
operated on the entire compound page, but now we can avoid calling
compound_head quite so many times.  Shrinks the function from 424 bytes
to 295 bytes (shrinking by 129 bytes).  The compatibility wrapper is 30
bytes, plus the 8 bytes for the exported symbol means the kernel shrinks
by 91 bytes.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 include/linux/swap.h |  3 ++-
 mm/folio-compat.c    |  7 +++++++
 mm/swap.c            | 34 ++++++++++++++++------------------
 3 files changed, 25 insertions(+), 19 deletions(-)

Comments

Vlastimil Babka Aug. 11, 2021, 2:50 p.m. UTC | #1
On 7/15/21 5:35 AM, Matthew Wilcox (Oracle) wrote:
> Convert mark_page_accessed() to folio_mark_accessed().  It already
> operated on the entire compound page, but now we can avoid calling
> compound_head quite so many times.  Shrinks the function from 424 bytes
> to 295 bytes (shrinking by 129 bytes).  The compatibility wrapper is 30
> bytes, plus the 8 bytes for the exported symbol means the kernel shrinks
> by 91 bytes.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

Question below:

> @@ -430,36 +430,34 @@ static void __lru_cache_activate_page(struct page *page)
>   * When a newly allocated page is not yet visible, so safe for non-atomic ops,
>   * __SetPageReferenced(page) may be substituted for mark_page_accessed(page).
>   */

The other patches converting whole functions rewrote also comments to be about
folios, but not this one?

> -void mark_page_accessed(struct page *page)
> +void folio_mark_accessed(struct folio *folio)
>  {
> -	page = compound_head(page);
> -
> -	if (!PageReferenced(page)) {
> -		SetPageReferenced(page);
> -	} else if (PageUnevictable(page)) {
> +	if (!folio_test_referenced(folio)) {
> +		folio_set_referenced(folio);
> +	} else if (folio_test_unevictable(folio)) {
>  		/*
>  		 * Unevictable pages are on the "LRU_UNEVICTABLE" list. But,
>  		 * this list is never rotated or maintained, so marking an
>  		 * evictable page accessed has no effect.
>  		 */

These comments too?

> -	} else if (!PageActive(page)) {
> +	} else if (!folio_test_active(folio)) {
>  		/*
>  		 * If the page is on the LRU, queue it for activation via
>  		 * lru_pvecs.activate_page. Otherwise, assume the page is on a
>  		 * pagevec, mark it active and it'll be moved to the active
>  		 * LRU on the next drain.
>  		 */
> -		if (PageLRU(page))
> -			folio_activate(page_folio(page));
> +		if (folio_test_lru(folio))
> +			folio_activate(folio);
>  		else
> -			__lru_cache_activate_page(page);
> -		ClearPageReferenced(page);
> -		workingset_activation(page_folio(page));
> +			__lru_cache_activate_folio(folio);
> +		folio_clear_referenced(folio);
> +		workingset_activation(folio);
>  	}
> -	if (page_is_idle(page))
> -		clear_page_idle(page);
> +	if (folio_test_idle(folio))
> +		folio_clear_idle(folio);
>  }
> -EXPORT_SYMBOL(mark_page_accessed);
> +EXPORT_SYMBOL(folio_mark_accessed);
>  
>  /**
>   * lru_cache_add - add a page to a page list
>
diff mbox series

Patch

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 989d8f78c256..c7a4c0a5863d 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -352,7 +352,8 @@  extern void lru_note_cost(struct lruvec *lruvec, bool file,
 			  unsigned int nr_pages);
 extern void lru_note_cost_page(struct page *);
 extern void lru_cache_add(struct page *);
-extern void mark_page_accessed(struct page *);
+void mark_page_accessed(struct page *);
+void folio_mark_accessed(struct folio *);
 
 extern atomic_t lru_disable_count;
 
diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index 7044fcc8a8aa..a374747ae1c6 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c
@@ -5,6 +5,7 @@ 
  */
 
 #include <linux/pagemap.h>
+#include <linux/swap.h>
 
 struct address_space *page_mapping(struct page *page)
 {
@@ -41,3 +42,9 @@  bool page_mapped(struct page *page)
 	return folio_mapped(page_folio(page));
 }
 EXPORT_SYMBOL(page_mapped);
+
+void mark_page_accessed(struct page *page)
+{
+	folio_mark_accessed(page_folio(page));
+}
+EXPORT_SYMBOL(mark_page_accessed);
diff --git a/mm/swap.c b/mm/swap.c
index c3137e4e1cd8..d32007fe23b3 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -390,7 +390,7 @@  static void folio_activate(struct folio *folio)
 }
 #endif
 
-static void __lru_cache_activate_page(struct page *page)
+static void __lru_cache_activate_folio(struct folio *folio)
 {
 	struct pagevec *pvec;
 	int i;
@@ -411,8 +411,8 @@  static void __lru_cache_activate_page(struct page *page)
 	for (i = pagevec_count(pvec) - 1; i >= 0; i--) {
 		struct page *pagevec_page = pvec->pages[i];
 
-		if (pagevec_page == page) {
-			SetPageActive(page);
+		if (pagevec_page == &folio->page) {
+			folio_set_active(folio);
 			break;
 		}
 	}
@@ -430,36 +430,34 @@  static void __lru_cache_activate_page(struct page *page)
  * When a newly allocated page is not yet visible, so safe for non-atomic ops,
  * __SetPageReferenced(page) may be substituted for mark_page_accessed(page).
  */
-void mark_page_accessed(struct page *page)
+void folio_mark_accessed(struct folio *folio)
 {
-	page = compound_head(page);
-
-	if (!PageReferenced(page)) {
-		SetPageReferenced(page);
-	} else if (PageUnevictable(page)) {
+	if (!folio_test_referenced(folio)) {
+		folio_set_referenced(folio);
+	} else if (folio_test_unevictable(folio)) {
 		/*
 		 * Unevictable pages are on the "LRU_UNEVICTABLE" list. But,
 		 * this list is never rotated or maintained, so marking an
 		 * evictable page accessed has no effect.
 		 */
-	} else if (!PageActive(page)) {
+	} else if (!folio_test_active(folio)) {
 		/*
 		 * If the page is on the LRU, queue it for activation via
 		 * lru_pvecs.activate_page. Otherwise, assume the page is on a
 		 * pagevec, mark it active and it'll be moved to the active
 		 * LRU on the next drain.
 		 */
-		if (PageLRU(page))
-			folio_activate(page_folio(page));
+		if (folio_test_lru(folio))
+			folio_activate(folio);
 		else
-			__lru_cache_activate_page(page);
-		ClearPageReferenced(page);
-		workingset_activation(page_folio(page));
+			__lru_cache_activate_folio(folio);
+		folio_clear_referenced(folio);
+		workingset_activation(folio);
 	}
-	if (page_is_idle(page))
-		clear_page_idle(page);
+	if (folio_test_idle(folio))
+		folio_clear_idle(folio);
 }
-EXPORT_SYMBOL(mark_page_accessed);
+EXPORT_SYMBOL(folio_mark_accessed);
 
 /**
  * lru_cache_add - add a page to a page list