We don't scan anonymous memory if we ran out of swap, neither should we do it in case memcg swap limit is hit, because swap out is impossible anyway. Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> --- include/linux/swap.h | 6 ++++++ mm/memcontrol.c | 13 +++++++++++++ mm/vmscan.c | 2 +- 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index 66ea62cf256d..e3344d8ca2e9 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_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) { @@ -564,6 +565,11 @@ static inline int mem_cgroup_charge_swap(struct page *page, swp_entry_t entry) 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 9d10e2819ec4..2ee823d62f80 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5826,6 +5826,19 @@ 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) + 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 b220e6cda25d..ab52d865d922 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1995,7 +1995,7 @@ 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; } -- 2.1.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>