On 05/22/2017 11:42 AM, Mike Rapoport wrote: > Currently applications can explicitly enable or disable THP for a memory > region using MADV_HUGEPAGE or MADV_NOHUGEPAGE. However, once either of > these advises is used, the region will always have > VM_HUGEPAGE/VM_NOHUGEPAGE flag set in vma->vm_flags. > The MADV_CLR_HUGEPAGE resets both these flags and allows managing THP in > the region according to system-wide settings.
Invoking madvise() for the first time with either MADV_HUGEPAGE or MADV_NOHUGEPAGE on the buffer will unsubscribe it from the system wide behavior for good. I am not saying we should not have a way to put it back into system wide mode but are there no other functions through madvise() or any other interface which may have the same situation.
