On Mon, Sep 28, 2020 at 08:21:10PM +0200, David Hildenbrand wrote: >As we no longer shuffle via generic_online_page() and when undoing >isolation, we can simplify the comment. > >We now effectively shuffle only once (properly) when onlining new >memory. > >Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >Cc: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx> >Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> >Cc: Michal Hocko <mhocko@xxxxxxxxxx> >Cc: Dave Hansen <dave.hansen@xxxxxxxxx> >Cc: Vlastimil Babka <vbabka@xxxxxxx> >Cc: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> >Cc: Oscar Salvador <osalvador@xxxxxxx> >Cc: Mike Rapoport <rppt@xxxxxxxxxx> >Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> >--- > mm/memory_hotplug.c | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) > >diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >index 9db80ee29caa..c589bd8801bb 100644 >--- a/mm/memory_hotplug.c >+++ b/mm/memory_hotplug.c >@@ -859,13 +859,10 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, > undo_isolate_page_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE); > > /* >- * When exposing larger, physically contiguous memory areas to the >- * buddy, shuffling in the buddy (when freeing onlined pages, putting >- * them either to the head or the tail of the freelist) is only helpful >- * for maintaining the shuffle, but not for creating the initial >- * shuffle. Shuffle the whole zone to make sure the just onlined pages >- * are properly distributed across the whole freelist. Make sure to >- * shuffle once pageblocks are no longer isolated. >+ * Freshly onlined pages aren't shuffled (e.g., all pages are placed to >+ * the tail of the freelist when undoing isolation). Shuffle the whole >+ * zone to make sure the just onlined pages are properly distributed >+ * across the whole freelist - to create an initial shuffle. > */ > shuffle_zone(zone); > >-- >2.26.2 -- Wei Yang Help you, Help me
