On Wed, Jun 05, 2019 at 02:57:59PM -0700, Dan Williams wrote: > Prepare for hot{plug,remove} of sub-ranges of a section by tracking a > sub-section active bitmask, each bit representing a PMD_SIZE span of the > architecture's memory hotplug section size. > > The implications of a partially populated section is that pfn_valid() > needs to go beyond a valid_section() check and read the sub-section > active ranges from the bitmask. The expectation is that the bitmask > (subsection_map) fits in the same cacheline as the valid_section() data, > so the incremental performance overhead to pfn_valid() should be > negligible. > > Cc: Michal Hocko <mho...@suse.com> > Cc: Vlastimil Babka <vba...@suse.cz> > Cc: Logan Gunthorpe <log...@deltatee.com> > Cc: Oscar Salvador <osalva...@suse.de> > Cc: Pavel Tatashin <pasha.tatas...@soleen.com> > Tested-by: Jane Chu <jane....@oracle.com> > Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
Reviewed-by: Oscar Salvador <osalva...@suse.de> -- Oscar Salvador SUSE L3