mm/swap: convert __page_cache_release() to use a folio

All the callers now have a folio.  Saves several calls to compound_head,
totalling 502 bytes of text.

Link: https://lkml.kernel.org/r/20220617175020.717127-19-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/swap.c b/mm/swap.c
index b709f3e..5f6caa6 100644 (file)
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -77,31 +77,30 @@ static DEFINE_PER_CPU(struct cpu_fbatches, cpu_fbatches) = {
  * This path almost never happens for VM activity - pages are normally freed
  * via pagevecs.  But it gets used by networking - and for compound pages.
  */
-static void __page_cache_release(struct page *page)
+static void __page_cache_release(struct folio *folio)
 {
-       if (PageLRU(page)) {
-               struct folio *folio = page_folio(page);
+       if (folio_test_lru(folio)) {
                struct lruvec *lruvec;
                unsigned long flags;
 
                lruvec = folio_lruvec_lock_irqsave(folio, &flags);
-               del_page_from_lru_list(page, lruvec);
-               __clear_page_lru_flags(page);
+               lruvec_del_folio(lruvec, folio);
+               __folio_clear_lru_flags(folio);
                unlock_page_lruvec_irqrestore(lruvec, flags);
        }
-       /* See comment on PageMlocked in release_pages() */
-       if (unlikely(PageMlocked(page))) {
-               int nr_pages = thp_nr_pages(page);
+       /* See comment on folio_test_mlocked in release_pages() */
+       if (unlikely(folio_test_mlocked(folio))) {
+               long nr_pages = folio_nr_pages(folio);
 
-               __ClearPageMlocked(page);
-               mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
+               __folio_clear_mlocked(folio);
+               zone_stat_mod_folio(folio, NR_MLOCK, -nr_pages);
                count_vm_events(UNEVICTABLE_PGCLEARED, nr_pages);
        }
 }
 
 static void __folio_put_small(struct folio *folio)
 {
-       __page_cache_release(&folio->page);
+       __page_cache_release(folio);
        mem_cgroup_uncharge(folio);
        free_unref_page(&folio->page, 0);
 }
@@ -115,7 +114,7 @@ static void __folio_put_large(struct folio *folio)
         * be called for hugetlb (it has a separate hugetlb_cgroup.)
         */
        if (!folio_test_hugetlb(folio))
-               __page_cache_release(&folio->page);
+               __page_cache_release(folio);
        destroy_compound_page(&folio->page);
 }
 
@@ -199,14 +198,14 @@ static void lru_add_fn(struct lruvec *lruvec, struct folio *folio)
 
        /*
         * Is an smp_mb__after_atomic() still required here, before
-        * folio_evictable() tests PageMlocked, to rule out the possibility
+        * folio_evictable() tests the mlocked flag, to rule out the possibility
         * of stranding an evictable folio on an unevictable LRU?  I think
-        * not, because __munlock_page() only clears PageMlocked while the LRU
-        * lock is held.
+        * not, because __munlock_page() only clears the mlocked flag
+        * while the LRU lock is held.
         *
         * (That is not true of __page_cache_release(), and not necessarily
-        * true of release_pages(): but those only clear PageMlocked after
-        * put_page_testzero() has excluded any other users of the page.)
+        * true of release_pages(): but those only clear the mlocked flag after
+        * folio_put_testzero() has excluded any other users of the folio.)
         */
        if (folio_evictable(folio)) {
                if (was_unevictable)