The patch titled Subject: mm/mempolicy.c: remove unnecessary nodemask check in kernel_migrate_pages() has been added to the -mm tree. Its filename is mm-mempolicyc-remove-unnecessary-nodemask-check-in-kernel_migrate_pages.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-mempolicyc-remove-unnecessary-nodemask-check-in-kernel_migrate_pages.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-mempolicyc-remove-unnecessary-nodemask-check-in-kernel_migrate_pages.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Subject: 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@xxxxxxxxxx Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mempolicy.c | 4 ---- 1 file changed, 4 deletions(-) --- a/mm/mempolicy.c~mm-mempolicyc-remove-unnecessary-nodemask-check-in-kernel_migrate_pages +++ a/mm/mempolicy.c @@ -1513,10 +1513,6 @@ static int kernel_migrate_pages(pid_t pi 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; _ Patches currently in -mm which might be from wangkefeng.wang@xxxxxxxxxx are mm-mempolicyc-remove-unnecessary-nodemask-check-in-kernel_migrate_pages.patch thp-update-split_huge_page_pmd-commnet.patch