From: Fengguang Wu <fengguang.wu@xxxxxxxxx> Subject: mm/swap.c: trivial mark_page_accessed() cleanup This avoids duplicated PageReferenced() calls. No behavior change. Link: http://lkml.kernel.org/r/20191016225326.GB12497@xxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Fengguang Wu <fengguang.wu@xxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Liu Jingqi <jingqi.liu@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/swap.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/mm/swap.c~mm-trivial-mark_page_accessed-cleanup +++ a/mm/swap.c @@ -373,9 +373,16 @@ static void __lru_cache_activate_page(st void mark_page_accessed(struct page *page) { page = compound_head(page); - if (!PageActive(page) && !PageUnevictable(page) && - PageReferenced(page)) { + if (!PageReferenced(page)) { + SetPageReferenced(page); + } else if (PageUnevictable(page)) { + /* + * Unevictable pages are on the "LRU_UNEVICTABLE" list. But, + * this list is never rotated or maintained, so marking an + * evictable page accessed has no effect. + */ + } else if (!PageActive(page)) { /* * If the page is on the LRU, queue it for activation via * activate_page_pvecs. Otherwise, assume the page is on a @@ -389,8 +396,6 @@ void mark_page_accessed(struct page *pag ClearPageReferenced(page); if (page_is_file_cache(page)) workingset_activation(page); - } else if (!PageReferenced(page)) { - SetPageReferenced(page); } if (page_is_idle(page)) clear_page_idle(page); _
