From 4406548ee39c2268876b61a927acad45da6f9aef Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Mon, 23 Sep 2019 15:37:01 -0700 Subject: [PATCH] mm/mempolicy.c: remove unnecessary nodemask check in kernel_migrate_pages() 1) task_nodes = cpuset_mems_allowed(current); -> cpuset_mems_allowed() guaranteed to return some non-empty subset of node_states[N_MEMORY]. 2) nodes_and(*new, *new, task_nodes); -> after nodes_and(), the 'new' should be empty or appropriate nodemask(online node and with memory). After 1) and 2), we could remove unnecessary check whether the 'new' AND node_states[N_MEMORY] is empty. Link: http://lkml.kernel.org/r/20190806023634.55356-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Vlastimil Babka Cc: Andrea Arcangeli Cc: Dan Williams Cc: Michal Hocko Cc: Oscar Salvador Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index f000771558d8..464406e8da91 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1512,10 +1512,6 @@ static int kernel_migrate_pages(pid_t pid, unsigned long maxnode, if (nodes_empty(*new)) goto out_put; - nodes_and(*new, *new, node_states[N_MEMORY]); - if (nodes_empty(*new)) - goto out_put; - err = security_task_movememory(task); if (err) goto out_put;