[RFC PATCH 11/11] mm/swap: Convert rotate_reclaimable_page to folio

[Matthew Wilcox (Oracle)]

Move the declaration into mm/internal.h and rename the function to
rotate_reclaimable_folio().  This eliminates all five of the calls to
compound_head() in this function.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
 include/linux/swap.h |  1 -
 mm/filemap.c         |  2 +-
 mm/internal.h        |  1 +
 mm/page_io.c         |  4 ++--
 mm/swap.c            | 12 ++++++------
 5 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 5bba15ac5a2e..5aaca35ce887 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -343,7 +343,6 @@ extern void lru_add_drain(void);
 extern void lru_add_drain_cpu(int cpu);
 extern void lru_add_drain_cpu_zone(struct zone *zone);
 extern void lru_add_drain_all(void);
-extern void rotate_reclaimable_page(struct page *page);
 extern void deactivate_file_page(struct page *page);
 extern void deactivate_page(struct page *page);
 extern void mark_page_lazyfree(struct page *page);
diff --git a/mm/filemap.c b/mm/filemap.c
index 297144524f58..93e40e9ac357 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1477,7 +1477,7 @@ void end_page_writeback(struct page *page)
 	 */
 	if (FolioReclaim(folio)) {
 		ClearFolioReclaim(folio);
-		rotate_reclaimable_page(&folio->page);
+		rotate_reclaimable_folio(folio);
 	}
 
 	/*
diff --git a/mm/internal.h b/mm/internal.h
index 8e9c660f33ca..f089535b5d86 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -35,6 +35,7 @@
 void page_writeback_init(void);
 
 vm_fault_t do_swap_page(struct vm_fault *vmf);
+void rotate_reclaimable_folio(struct folio *folio);
 
 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 		unsigned long floor, unsigned long ceiling);
diff --git a/mm/page_io.c b/mm/page_io.c
index 9bca17ecc4df..1fc0a579da58 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -57,7 +57,7 @@ void end_swap_bio_write(struct bio *bio)
 		 * Also print a dire warning that things will go BAD (tm)
 		 * very quickly.
 		 *
-		 * Also clear PG_reclaim to avoid rotate_reclaimable_page()
+		 * Also clear PG_reclaim to avoid rotate_reclaimable_folio()
 		 */
 		set_page_dirty(page);
 		pr_alert("Write-error on swap-device (%u:%u:%llu)\n",
@@ -341,7 +341,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 			 * temporary failure if the system has limited
 			 * memory for allocating transmit buffers.
 			 * Mark the page dirty and avoid
-			 * rotate_reclaimable_page but rate-limit the
+			 * rotate_reclaimable_folio but rate-limit the
 			 * messages but do not flag PageError like
 			 * the normal direct-to-bio case as it could
 			 * be temporary.
diff --git a/mm/swap.c b/mm/swap.c
index 5022dfe388ad..9aadde8aea9b 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -241,19 +241,19 @@ static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec)
  * reclaim.  If it still appears to be reclaimable, move it to the tail of the
  * inactive list.
  *
- * rotate_reclaimable_page() must disable IRQs, to prevent nasty races.
+ * rotate_reclaimable_folio() must disable IRQs, to prevent nasty races.
  */
-void rotate_reclaimable_page(struct page *page)
+void rotate_reclaimable_folio(struct folio *folio)
 {
-	if (!PageLocked(page) && !PageDirty(page) &&
-	    !PageUnevictable(page) && PageLRU(page)) {
+	if (!FolioLocked(folio) && !FolioDirty(folio) &&
+	    !FolioUnevictable(folio) && FolioLRU(folio)) {
 		struct pagevec *pvec;
 		unsigned long flags;
 
-		get_page(page);
+		get_folio(folio);
 		local_lock_irqsave(&lru_rotate.lock, flags);
 		pvec = this_cpu_ptr(&lru_rotate.pvec);
-		if (!pagevec_add(pvec, page) || PageCompound(page))
+		if (!pagevec_add(pvec, &folio->page) || FolioHead(folio))
 			pagevec_lru_move_fn(pvec, pagevec_move_tail_fn);
 		local_unlock_irqrestore(&lru_rotate.lock, flags);
 	}
-- 
2.29.2