On 15 Jul 2021, at 1:51, Huang Ying wrote: > From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> > > Reclaim-based migration is attempting to optimize data placement in > memory based on the system topology. If the system changes, so must > the migration ordering. > > The implementation is conceptually simple and entirely unoptimized. > On any memory or CPU hotplug events, assume that a node was added or > removed and recalculate all migration targets. This ensures that the > node_demotion[] array is always ready to be used in case the new > reclaim mode is enabled. > > This recalculation is far from optimal, most glaringly that it does > not even attempt to figure out the hotplug event would have some > *actual* effect on the demotion order. But, given the expected > paucity of hotplug events, this should be fine. > > Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> > Signed-off-by: "Huang, Ying" <ying.huang@xxxxxxxxx> > Reviewed-by: Yang Shi <shy828301@xxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxx> > Cc: Wei Xu <weixugc@xxxxxxxxxx> > Cc: Zi Yan <ziy@xxxxxxxxxx> > Cc: osalvador <osalvador@xxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > Cc: David Hildenbrand <david@xxxxxxxxxx> > > -- > > Changes since 20210618: > * moved RCU part to the prev patch in series. > > Changes since 20210302: > * remove duplicate synchronize_rcu() > --- > mm/migrate.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 89 insertions(+), 1 deletion(-) LGTM. Reviewed-by: Zi Yan <ziy@xxxxxxxxxx> — Best Regards, Yan, Zi
Attachment:
signature.asc
Description: OpenPGP digital signature
