From: Kaixu Xia <kaixuxia@xxxxxxxxxxx> Subject: mm: memcontrol: simplify value comparison between count and limit When the variables count and limit have the same value(count == limit), the result of min(margin, limit - count) statement should be 0 and the variable margin is set to 0. So in this case, the min() statement is not necessary and we can directly set the variable margin to 0. Link: http://lkml.kernel.org/r/1587479661-27237-1-git-send-email-kaixuxia@xxxxxxxxxxx Signed-off-by: Kaixu Xia <kaixuxia@xxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/memcontrol.c~mm-memcontrol-simplify-value-comparison-between-count-and-limit +++ a/mm/memcontrol.c @@ -1314,7 +1314,7 @@ static unsigned long mem_cgroup_margin(s if (do_memsw_account()) { count = page_counter_read(&memcg->memsw); limit = READ_ONCE(memcg->memsw.max); - if (count <= limit) + if (count < limit) margin = min(margin, limit - count); else margin = 0; _
