On Mon, Jun 29, 2020 at 11:50:15AM -0700, David Rientjes wrote: > On Tue, 30 Jun 2020, Su Hui wrote: > > > remove the redundancy code, the zone_start_pfn > > is assigned from zone->zone_start_pfn > > Signed-off-by: Su Hui <sh_def@xxxxxxx> > > I don't think this is redundant, it's used by memory hotplug when onlining > new memory. Right, it is: $ git grep -wn init_currently_empty_zone mm/memory_hotplug.c mm/memory_hotplug.c:697: init_currently_empty_zone(zone, start_pfn, nr_pages); > > --- > > mm/page_alloc.c | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index 3c4eb750a199..3372a8c9fbc4 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > > @@ -6215,8 +6215,6 @@ void __meminit init_currently_empty_zone(struct zone *zone, > > if (zone_idx > pgdat->nr_zones) > > pgdat->nr_zones = zone_idx; > > > > - zone->zone_start_pfn = zone_start_pfn; > > - > > mminit_dprintk(MMINIT_TRACE, "memmap_init", > > "Initialising map node %d zone %lu pfns %lu -> %lu\n", > > pgdat->node_id, > -- Sincerely yours, Mike.