On 02/05/20 at 02:20pm, David Hildenbrand wrote: > On 05.02.20 13:43, Baoquan He wrote: > > On 02/04/20 at 03:42pm, David Hildenbrand wrote: > >> On 04.02.20 15:25, Baoquan He wrote: > >>> On 10/06/19 at 10:56am, David Hildenbrand wrote: > >>>> If we have holes, the holes will automatically get detected and removed > >>>> once we remove the next bigger/smaller section. The extra checks can > >>>> go. > >>>> > >>>> Cc: Andrew Morton <[email protected]> > >>>> Cc: Oscar Salvador <[email protected]> > >>>> Cc: Michal Hocko <[email protected]> > >>>> Cc: David Hildenbrand <[email protected]> > >>>> Cc: Pavel Tatashin <[email protected]> > >>>> Cc: Dan Williams <[email protected]> > >>>> Cc: Wei Yang <[email protected]> > >>>> Signed-off-by: David Hildenbrand <[email protected]> > >>>> --- > >>>> mm/memory_hotplug.c | 34 +++++++--------------------------- > >>>> 1 file changed, 7 insertions(+), 27 deletions(-) > >>>> > >>>> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > >>>> index f294918f7211..8dafa1ba8d9f 100644 > >>>> --- a/mm/memory_hotplug.c > >>>> +++ b/mm/memory_hotplug.c > >>>> @@ -393,6 +393,9 @@ static void shrink_zone_span(struct zone *zone, > >>>> unsigned long start_pfn, > >>>> if (pfn) { > >>>> zone->zone_start_pfn = pfn; > >>>> zone->spanned_pages = zone_end_pfn - pfn; > >>>> + } else { > >>>> + zone->zone_start_pfn = 0; > >>>> + zone->spanned_pages = 0; > >>>> } > >>>> } else if (zone_end_pfn == end_pfn) { > >>>> /* > >>>> @@ -405,34 +408,11 @@ static void shrink_zone_span(struct zone *zone, > >>>> unsigned long start_pfn, > >>>> start_pfn); > >>>> if (pfn) > >>>> zone->spanned_pages = pfn - zone_start_pfn + 1; > >>>> + else { > >>>> + zone->zone_start_pfn = 0; > >>>> + zone->spanned_pages = 0; > >>> > >>> Thinking in which case (zone_start_pfn != start_pfn) and it comes here. > >> > >> Could only happen in case the zone_start_pfn would have been "out of the > >> zone already". If you ask me: unlikely :) > > > > Yeah, I also think it's unlikely to come here. > > > > The 'if (zone_start_pfn == start_pfn)' checking also covers the case > > (zone_start_pfn == start_pfn && zone_end_pfn == end_pfn). So this > > zone_start_pfn/spanned_pages resetting can be removed to avoid > > confusion. > > At least I would find it more confusing without it (or want a comment > explaining why this does not have to be handled and why the !pfn case is > not possible).
I don't get why being w/o it will be more confusing, but it's OK since it doesn't impact anything. > > Anyhow, that patch is already upstream and I don't consider this high > priority. Thanks :) Yeah, noticed you told Wei the status in another patch thread, I am fine with it, just leave it to you to decide. Thanks.
