On 04/23/20 at 08:55am, Mike Rapoport wrote: > On Thu, Apr 23, 2020 at 10:57:20AM +0800, Baoquan He wrote: > > On 04/23/20 at 10:53am, Baoquan He wrote: > > > On 04/12/20 at 10:48pm, Mike Rapoport wrote: > > > > From: Mike Rapoport <r...@linux.ibm.com> > > > > > > > > Some architectures (e.g. ARC) have the ZONE_HIGHMEM zone below the > > > > ZONE_NORMAL. Allowing free_area_init() parse max_zone_pfn array even it > > > > is > > > > sorted in descending order allows using free_area_init() on such > > > > architectures. > > > > > > > > Add top -> down traversal of max_zone_pfn array in free_area_init() and > > > > use > > > > the latter in ARC node/zone initialization. > > > > > > Or maybe leave ARC as is. The change in this patchset doesn't impact > > > ARC's handling about zone initialization, leaving it as is can reduce > > > the complication in implementation of free_area_init(), which is a > > > common function. So I personally don't see a strong motivation to have > > > this patch. > > > > OK, seems this patch is prepared to simplify free_area_init_node(), so > > take back what I said at above. > > > > Then this looks necessary, even though it introduces special case into > > common function free_area_init(). > > The idea is to have a single free_area_init() for all architectures > without keeping two completely different ways of calculating the zone > extents. > Another thing, is that with this we could eventually switch ARC from > DISCONTIGMEM.
Yeah, I think uniting them into a single free_area_init() is a great idea. Even though I had been through this patchset, when looked into each of them, still may forget the detail in later patch :)
