[QUESTION] Is MPOL_F_MOF user visible?

[Yang Shi <yang.shi@linux.alibaba.com>]

Hi folks,


When reading the mempolicy code, I got confused by MPOL_F_MOF flag. It 
is defined in include/uapi/linux/mempolicy.h, so it looks visible to the 
users. But, man page doesn't mention it at all. And, the code in 
do_set_mempolicy() -> mpol_new() doesn't set it. It looks it is just set 
by two places:

     - NUMA default policy (preferred_node_policy)

     - When MPOL_MF_LAZY is passed in. But, it is not configurable from 
user since it is not valid MF


So, actually it can't be set by user with set_mempolicy()/mbind() APIs, 
right? As long as the process' or vmas' policy is changed to non-default 
one (i.e. MPOL_BIND), those processes or vmas are *not* eligible for 
migrating with NUMA balancing anymore?


Thanks,

Yang