diff --git a/include/linux/swap.h b/include/linux/swap.h index c2bd163a5e7e..a587050204f9 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -551,6 +551,7 @@ static inline int mem_cgroup_swappiness(struct mem_cgroup *mem) extern void mem_cgroup_swapout(struct page *page, swp_entry_t entry); extern int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry); extern void mem_cgroup_uncharge_swap(swp_entry_t entry); +extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg); #else static inline void mem_cgroup_swapout(struct page *page, swp_entry_t entry) { @@ -565,6 +566,11 @@ static inline int mem_cgroup_try_charge_swap(struct page *page, static inline void mem_cgroup_uncharge_swap(swp_entry_t entry) { } + +static inline long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) +{ + return get_nr_swap_pages(); +} #endif #endif /* __KERNEL__*/ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1ff552e3722b..bcb38718e174 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5748,6 +5748,19 @@ void mem_cgroup_uncharge_swap(swp_entry_t entry) rcu_read_unlock(); } +long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) +{ + long nr_swap_pages = get_nr_swap_pages(); + + if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) + return nr_swap_pages; + for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) + nr_swap_pages = min_t(long, nr_swap_pages, + READ_ONCE(memcg->swap.limit) - + page_counter_read(&memcg->swap)); + return nr_swap_pages; +} + /* for remember boot option*/ #ifdef CONFIG_MEMCG_SWAP_ENABLED static int really_do_swap_account __initdata = 1; diff --git a/mm/vmscan.c b/mm/vmscan.c index 9a8556e49cd9..3be5f9db6c42 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2004,7 +2004,7 @@ static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg, force_scan = true; /* If we have no swap space, do not bother scanning anon pages. */ - if (!sc->may_swap || (get_nr_swap_pages() <= 0)) { + if (!sc->may_swap || mem_cgroup_get_nr_swap_pages(memcg) <= 0) { scan_balance = SCAN_FILE; goto out; }