Commit a11b9419 authored Apr 06, 2020 by David Hildenbrand Committed by Linus Torvalds Apr 07, 2020

mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages()



In commit 52fb87c8 ("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.

Suggested-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.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>
Link: http://lkml.kernel.org/r/20200228095819.10750-2-david@redhat.com


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent f3cd4c86

mm/memory_hotplug.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -534,7 +534,8 @@ void __remove_pages(unsigned long pfn, unsigned long nr_pages,
		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;
		}

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