From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/memory_hotplug.c: cleanup __add_pages() Let's drop the basically unused section stuff and simplify. The logic now matches the logic in __remove_pages(). Link: http://lkml.kernel.org/r/20200228095819.10750-3-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Baoquan He <bhe@xxxxxxxxxx> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx> Cc: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) --- a/mm/memory_hotplug.c~mm-memory_hotplug-cleanup-__add_pages +++ a/mm/memory_hotplug.c @@ -307,8 +307,9 @@ static int check_hotplug_memory_addressa int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages, struct mhp_restrictions *restrictions) { + const unsigned long end_pfn = pfn + nr_pages; + unsigned long cur_nr_pages; int err; - unsigned long nr, start_sec, end_sec; struct vmem_altmap *altmap = restrictions->altmap; err = check_hotplug_memory_addressable(pfn, nr_pages); @@ -331,18 +332,13 @@ int __ref __add_pages(int nid, unsigned if (err) return err; - 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; - - pfns = min(nr_pages, PAGES_PER_SECTION - - (pfn & ~PAGE_SECTION_MASK)); - err = sparse_add_section(nid, pfn, pfns, altmap); + for (; pfn < end_pfn; pfn += cur_nr_pages) { + /* Select all remaining pages up to the next section boundary */ + cur_nr_pages = min(end_pfn - pfn, + SECTION_ALIGN_UP(pfn + 1) - pfn); + err = sparse_add_section(nid, pfn, cur_nr_pages, altmap); if (err) break; - pfn += pfns; - nr_pages -= pfns; cond_resched(); } vmemmap_populate_print_last(); _
