proc: convert smaps_page_accumulate to use a folio

Replaces three calls to compound_head() with one.  Shrinks the function
from 2614 bytes to 1112 bytes in an allmodconfig build.

Link: https://lkml.kernel.org/r/20240403171456.1445117-3-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/proc/task_mmu.c

@@ -414,11 +414,12 @@ static void smaps_page_accumulate(struct mem_size_stats *mss,
 		struct page *page, unsigned long size, unsigned long pss,
 		bool dirty, bool locked, bool private)
 {
+	struct folio *folio = page_folio(page);
 	mss->pss += pss;
 
-	if (PageAnon(page))
+	if (folio_test_anon(folio))
 		mss->pss_anon += pss;
-	else if (PageSwapBacked(page))
+	else if (folio_test_swapbacked(folio))
 		mss->pss_shmem += pss;
 	else
 		mss->pss_file += pss;
@@ -426,7 +427,7 @@ static void smaps_page_accumulate(struct mem_size_stats *mss,
 	if (locked)
 		mss->pss_locked += pss;
 
-	if (dirty || PageDirty(page)) {
+	if (dirty || folio_test_dirty(folio)) {
 		mss->pss_dirty += pss;
 		if (private)
 			mss->private_dirty += size;