mm/memcg: Convert mem_cgroup_move_account() to use a folio

This saves dozens of bytes of text by eliminating a lot of calls to
compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 23fe124..c17681d 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5567,38 +5567,39 @@ static int mem_cgroup_move_account(struct page *page,
                                   struct mem_cgroup *from,
                                   struct mem_cgroup *to)
 {
+       struct folio *folio = page_folio(page);
        struct lruvec *from_vec, *to_vec;
        struct pglist_data *pgdat;
-       unsigned int nr_pages = compound ? thp_nr_pages(page) : 1;
+       unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1;
        int nid, ret;
 
        VM_BUG_ON(from == to);
-       VM_BUG_ON_PAGE(PageLRU(page), page);
-       VM_BUG_ON(compound && !PageTransHuge(page));
+       VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
+       VM_BUG_ON(compound && !folio_test_multi(folio));
 
        /*
         * Prevent mem_cgroup_migrate() from looking at
         * page's memory cgroup of its source page while we change it.
         */
        ret = -EBUSY;
-       if (!trylock_page(page))
+       if (!folio_trylock(folio))
                goto out;
 
        ret = -EINVAL;
-       if (page_memcg(page) != from)
+       if (folio_memcg(folio) != from)
                goto out_unlock;
 
-       pgdat = page_pgdat(page);
+       pgdat = folio_pgdat(folio);
        from_vec = mem_cgroup_lruvec(from, pgdat);
        to_vec = mem_cgroup_lruvec(to, pgdat);
 
-       lock_page_memcg(page);
+       folio_memcg_lock(folio);
 
-       if (PageAnon(page)) {
-               if (page_mapped(page)) {
+       if (folio_test_anon(folio)) {
+               if (folio_mapped(folio)) {
                        __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages);
                        __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages);
-                       if (PageTransHuge(page)) {
+                       if (folio_test_transhuge(folio)) {
                                __mod_lruvec_state(from_vec, NR_ANON_THPS,
                                                   -nr_pages);
                                __mod_lruvec_state(to_vec, NR_ANON_THPS,
@@ -5609,18 +5610,18 @@ static int mem_cgroup_move_account(struct page *page,
                __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages);
                __mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages);
 
-               if (PageSwapBacked(page)) {
+               if (folio_test_swapbacked(folio)) {
                        __mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages);
                        __mod_lruvec_state(to_vec, NR_SHMEM, nr_pages);
                }
 
-               if (page_mapped(page)) {
+               if (folio_mapped(folio)) {
                        __mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
                        __mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
                }
 
-               if (PageDirty(page)) {
-                       struct address_space *mapping = page_mapping(page);
+               if (folio_test_dirty(folio)) {
+                       struct address_space *mapping = folio_mapping(folio);
 
                        if (mapping_can_writeback(mapping)) {
                                __mod_lruvec_state(from_vec, NR_FILE_DIRTY,
@@ -5631,7 +5632,7 @@ static int mem_cgroup_move_account(struct page *page,
                }
        }
 
-       if (PageWriteback(page)) {
+       if (folio_test_writeback(folio)) {
                __mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages);
                __mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages);
        }
@@ -5654,12 +5655,12 @@ static int mem_cgroup_move_account(struct page *page,
        css_get(&to->css);
        css_put(&from->css);
 
-       page->memcg_data = (unsigned long)to;
+       folio->memcg_data = (unsigned long)to;
 
        __folio_memcg_unlock(from);
 
        ret = 0;
-       nid = page_to_nid(page);
+       nid = folio_nid(folio);
 
        local_irq_disable();
        mem_cgroup_charge_statistics(to, nr_pages);
@@ -5668,7 +5669,7 @@ static int mem_cgroup_move_account(struct page *page,
        memcg_check_events(from, nid);
        local_irq_enable();
 out_unlock:
-       unlock_page(page);
+       folio_unlock(folio);
 out:
        return ret;
 }