On 2023/10/10 16:17, Huang, Ying wrote:
Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> writes:
At present, only arc/sparc/m68k define WANT_PAGE_VIRTUAL, both of
them don't support numa balancing, and the page struct is aligned
to _struct_page_alignment, it is safe to move _last_cpupid before
'virtual' in page, meanwhile, add it into folio, which make us to
use folio->_last_cpupid directly.
Add BUILD_BUG_ON() to check this automatically?
The WANT_PAGE_VIRTUAL and LAST_CPUPID_NOT_IN_PAGE_FLAGS are not
conflict, the check is to make sure that the re-order the virtual
and _last_cpupid is minimal impact, and there is a build warning in
mm/memory.c when the LAST_CPUPID_NOT_IN_PAGE_FLAGS is enabled, so I
don't think we need a new BUILD_BUG_ON here.
Thanks.
--
Best Regards,
Huang, Ying
