From 4d1c627389c8ba6d9e703208567ffcdbd356f682 Mon Sep 17 00:00:00 2001 From: Daisuke Nishimura Date: Thu, 15 Jan 2009 13:51:14 -0800 Subject: [PATCH] memcg: make oom less frequently In previous implementation, mem_cgroup_try_charge checked the return value of mem_cgroup_try_to_free_pages, and just retried if some pages had been reclaimed. But now, try_charge(and mem_cgroup_hierarchical_reclaim called from it) only checks whether the usage is less than the limit. This patch tries to change the behavior as before to cause oom less frequently. Signed-off-by: Daisuke Nishimura Acked-by: Balbir Singh Acked-by: KAMEZAWA Hiroyuki Cc: Pavel Emelyanov Cc: Li Zefan Cc: Paul Menage Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 322625f551c2..fb62b4335fa9 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -773,10 +773,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, * but there might be left over accounting, even after children * have left. */ - ret = try_to_free_mem_cgroup_pages(root_mem, gfp_mask, noswap, + ret += try_to_free_mem_cgroup_pages(root_mem, gfp_mask, noswap, get_swappiness(root_mem)); if (mem_cgroup_check_under_limit(root_mem)) - return 0; + return 1; /* indicate reclaim has succeeded */ if (!root_mem->use_hierarchy) return ret; @@ -787,10 +787,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, next_mem = mem_cgroup_get_next_node(root_mem); continue; } - ret = try_to_free_mem_cgroup_pages(next_mem, gfp_mask, noswap, + ret += try_to_free_mem_cgroup_pages(next_mem, gfp_mask, noswap, get_swappiness(next_mem)); if (mem_cgroup_check_under_limit(root_mem)) - return 0; + return 1; /* indicate reclaim has succeeded */ next_mem = mem_cgroup_get_next_node(root_mem); } return ret; @@ -875,6 +875,8 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask, noswap); + if (ret) + continue; /* * try_to_free_mem_cgroup_pages() might not give us a full -- 2.20.1