lkml.org 
[lkml]   [2019]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] mm/hotplug: fix offline undo_isolate_page_range()
On Thu 14-03-19 09:09:22, Oscar Salvador wrote:
> On Wed, Mar 13, 2019 at 10:31:33AM -0400, Qian Cai wrote:
> > Also, after calling the "useless" undo_isolate_page_range() here, it
> > reaches the point of no returning by notifying MEM_OFFLINE. Those pages
> > will be marked as MIGRATE_MOVABLE again once onlining. The only thing
> > left to do is to decrease the number of isolated pageblocks zone
> > counter which would make some paths of the page allocation slower that
> > the above commit introduced. A memory block is usually at most 1GiB in
> > size, so an "int" should be enough to represent the number of pageblocks
> > in a block. Fix an incorrect comment along the way.
>
> Well, x86_64's memblocks can be up to 2GB depending on the memory we got.
> Plus the fact that alloc_contig_range can be used to isolate 16GB-hugetlb
> pages on powerpc, and that could be a lot of pageblocks.
>
> While an "int" could still hold, I think we should use "long" just to be
> more future-proof.

I would rather not touch that for now. If we really need to change the
type then do it when it is really needed. I pressume more things would
have to be changed anyway.

--
Michal Hocko
SUSE Labs

\
 
 \ /
  Last update: 2019-03-14 09:23    [W:1.013 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site