[PATCH v6 10/10] mm/memory_hotplug: Cleanup __remove_pages()

David Hildenbrand
2019-10-06T08:57:48Z

Let's drop the basically unused section stuff and simplify.

Also, let's use a shorter variant to calculate the number of pages to
the next section boundary.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/memory_hotplug.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 843481bd507d..2275240cfa10 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -490,25 +490,20 @@ static void __remove_section(unsigned long pfn, unsigned long nr_pages,
void __remove_pages(unsigned long pfn, unsigned long nr_pages,
struct vmem_altmap *altmap)
{
+ const unsigned long end_pfn = pfn + nr_pages;
+ unsigned long cur_nr_pages;
unsigned long map_offset = 0;
- unsigned long nr, start_sec, end_sec;

map_offset = vmem_altmap_offset(altmap);

if (check_pfn_span(pfn, nr_pages, "remove"))
return;

- start_sec = pfn_to_section_nr(pfn);
- end_sec = pfn_to_section_nr(pfn + nr_pages - 1);
- for (nr = start_sec; nr <= end_sec; nr++) {
- unsigned long pfns;
-
+ for (; pfn < end_pfn; pfn += cur_nr_pages) {
cond_resched();
- pfns = min(nr_pages, PAGES_PER_SECTION
- - (pfn & ~PAGE_SECTION_MASK));
- __remove_section(pfn, pfns, map_offset, altmap);
- pfn += pfns;
- nr_pages -= pfns;
+ /* Select all remaining pages up to the next section boundary */
+ cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK));
+ __remove_section(pfn, cur_nr_pages, map_offset, altmap);
map_offset = 0;
}
}
--
2.21.0