[056/166] mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages()
diff mbox series

Message ID 20200407030653.PJ_dMcGKr%akpm@linux-foundation.org
State New
Headers show
Series
  • [001/166] mm, memcg: bypass high reclaim iteration for cgroup hierarchy root
Related show

Commit Message

Andrew Morton April 7, 2020, 3:06 a.m. UTC
From: David Hildenbrand <david@redhat.com>
Subject: mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages()

In commit 52fb87c81f11 ("mm/memory_hotplug: cleanup __remove_pages()"), we
cleaned up __remove_pages(), and introduced a shorter variant to calculate
the number of pages to the next section boundary.

Turns out we can make this calculation easier to read.  We always want to
have the number of pages (> 0) to the next section boundary, starting from
the current pfn.

We'll clean up __remove_pages() in a follow-up patch and directly make use
of this computation.

Link: http://lkml.kernel.org/r/20200228095819.10750-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Segher Boessenkool <segher@kernel.crashing.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory_hotplug.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Patch
diff mbox series

--- a/mm/memory_hotplug.c~mm-memory_hotplug-simplify-calculation-of-number-of-pages-in-__remove_pages
+++ a/mm/memory_hotplug.c
@@ -534,7 +534,8 @@  void __remove_pages(unsigned long pfn, u
 	for (; pfn < end_pfn; pfn += cur_nr_pages) {
 		cond_resched();
 		/* Select all remaining pages up to the next section boundary */
-		cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK));
+		cur_nr_pages = min(end_pfn - pfn,
+				   SECTION_ALIGN_UP(pfn + 1) - pfn);
 		__remove_section(pfn, cur_nr_pages, map_offset, altmap);
 		map_offset = 0;
 	}