On 2/6/22 22:34, Hugh Dickins wrote: > munlock_vma_pages_range() will still be required, when munlocking but > not munmapping a set of pages; but when unmapping a pte, the mlock count > will be maintained in much the same way as it will be maintained when > mapping in the pte. Which removes the need for munlock_vma_pages_all() > on mlocked vmas when munmapping or exiting: eliminating the catastrophic > contention on i_mmap_rwsem, and the need for page lock on the pages. > > There is still a need to update locked_vm accounting according to the > munmapped vmas when munmapping: do that in detach_vmas_to_be_unmapped(). > exit_mmap() does not need locked_vm updates, so delete unlock_range(). > > And wasn't I the one who forbade the OOM reaper to attack mlocked vmas, > because of the uncertainty in blocking on all those page locks? > No fear of that now, so permit the OOM reaper on mlocked vmas. > > Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
