mm: thp: calculate the mapcount correctly for THP pages during WP faults

[deliverable/linux.git] / include / linux / swap.h

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 2b83359c19cabee6dc211c887518d001f05081f4..ad220359f1b072cfbf29456871312bbf07d5cceb 100644 (file)
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -418,7 +418,7 @@ extern sector_t swapdev_block(int, pgoff_t);
 extern int page_swapcount(struct page *);
 extern int swp_swapcount(swp_entry_t entry);
 extern struct swap_info_struct *page_swap_info(struct page *);
-extern int reuse_swap_page(struct page *);
+extern bool reuse_swap_page(struct page *, int *);
 extern int try_to_free_swap(struct page *);
 struct backing_dev_info;
 
@@ -513,8 +513,8 @@ static inline int swp_swapcount(swp_entry_t entry)
        return 0;
 }
 
-#define reuse_swap_page(page) \
-       (!PageTransCompound(page) && page_mapcount(page) == 1)
+#define reuse_swap_page(page, total_mapcount) \
+       (page_trans_huge_mapcount(page, total_mapcount) == 1)
 
 static inline int try_to_free_swap(struct page *page)
 {
@@ -533,6 +533,10 @@ static inline swp_entry_t get_swap_page(void)
 #ifdef CONFIG_MEMCG
 static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg)
 {
+       /* Cgroup2 doesn't have per-cgroup swappiness */
+       if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
+               return vm_swappiness;
+
        /* root ? */
        if (mem_cgroup_disabled() || !memcg->css.parent)
                return vm_swappiness;