[PATCH v13 057/137] mm/swap: Add folio_activate()

Matthew Wilcox (Oracle)
2021-07-12T03:38:51Z

This replaces activate_page() and eliminates lots of calls to
compound_head(). Saves net 118 bytes of kernel text. There are still
some redundant calls to page_folio() here which will be removed when
pagevec_lru_move_fn() is converted to use folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
mm/swap.c | 43 +++++++++++++++++++++++--------------------
1 file changed, 23 insertions(+), 20 deletions(-)

diff --git a/mm/swap.c b/mm/swap.c
index 5c681c01e3fa..253ac77792dc 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -322,15 +322,15 @@ void lru_note_cost_page(struct page *page)
page_is_file_lru(page), thp_nr_pages(page));
}

-static void __activate_page(struct page *page, struct lruvec *lruvec)
+static void __folio_activate(struct folio *folio, struct lruvec *lruvec)
{
- if (!PageActive(page) && !PageUnevictable(page)) {
- int nr_pages = thp_nr_pages(page);
+ if (!folio_active(folio) && !folio_unevictable(folio)) {
+ int nr_pages = folio_nr_pages(folio);

- del_page_from_lru_list(page, lruvec);
- SetPageActive(page);
- add_page_to_lru_list(page, lruvec);
- trace_mm_lru_activate(page);
+ folio_del_from_lru_list(folio, lruvec);
+ folio_set_active_flag(folio);
+ folio_add_to_lru_list(folio, lruvec);
+ trace_mm_lru_activate(&folio->page);

__count_vm_events(PGACTIVATE, nr_pages);
__count_memcg_events(lruvec_memcg(lruvec), PGACTIVATE,
@@ -339,6 +339,11 @@ static void __activate_page(struct page *page, struct lruvec *lruvec)
}

#ifdef CONFIG_SMP
+static void __activate_page(struct page *page, struct lruvec *lruvec)
+{
+ return __folio_activate(page_folio(page), lruvec);
+}
+
static void activate_page_drain(int cpu)
{
struct pagevec *pvec = &per_cpu(lru_pvecs.activate_page, cpu);
@@ -352,16 +357,16 @@ static bool need_activate_page_drain(int cpu)
return pagevec_count(&per_cpu(lru_pvecs.activate_page, cpu)) != 0;
}

-static void activate_page(struct page *page)
+static void folio_activate(struct folio *folio)
{
- page = compound_head(page);
- if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+ if (folio_lru(folio) && !folio_active(folio) &&
+ !folio_unevictable(folio)) {
struct pagevec *pvec;

+ folio_get(folio);
local_lock(&lru_pvecs.lock);
pvec = this_cpu_ptr(&lru_pvecs.activate_page);
- get_page(page);
- if (pagevec_add_and_need_flush(pvec, page))
+ if (pagevec_add_and_need_flush(pvec, &folio->page))
pagevec_lru_move_fn(pvec, __activate_page);
local_unlock(&lru_pvecs.lock);
}
@@ -372,17 +377,15 @@ static inline void activate_page_drain(int cpu)
{
}

-static void activate_page(struct page *page)
+static void folio_activate(struct folio *folio)
{
- struct folio *folio = page_folio(page);
struct lruvec *lruvec;

- page = &folio->page;
- if (TestClearPageLRU(page)) {
- lruvec = folio_lruvec_lock_irq(folio);
- __activate_page(page, lruvec);
+ if (folio_test_clear_lru_flag(folio)) {
+ lruvec = folio_lock_lruvec_irq(folio);
+ __folio_activate(folio, lruvec);
unlock_page_lruvec_irq(lruvec);
- SetPageLRU(page);
+ folio_set_lru_flag(folio);
}
}
#endif
@@ -447,7 +450,7 @@ void mark_page_accessed(struct page *page)
* LRU on the next drain.
*/
if (PageLRU(page))
- activate_page(page);
+ folio_activate(page_folio(page));
else
__lru_cache_activate_page(page);
ClearPageReferenced(page);
--
2.30.2