On Wed 18-05-16 15:24:15, roy.qing.li@xxxxxxxxx wrote: > From: Li RongQing <roy.qing.li@xxxxxxxxx> > > when memory+swap is over limit, return 0 > > Signed-off-by: Li RongQing <roy.qing.li@xxxxxxxxx> > --- > mm/memcontrol.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index fe787f5..e9211c2 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1090,6 +1090,8 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) > limit = READ_ONCE(memcg->memsw.limit); > if (count <= limit) > margin = min(margin, limit - count); > + else > + margin = 0; count should always be smaller than memsw.limit (this is a hard limit). Even if we have some temporary breach then the code should work as expected because margin is initialized to 0 and memsw.limit >= limit. Or have you seen any real problem with this code path? -- Michal Hocko SUSE Labs -- 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>