From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/memory_hotplug: remove is_mem_section_removable() Fortunately, all users of is_mem_section_removable() are gone. Get rid of it, including some now unnecessary functions. Link: http://lkml.kernel.org/r/20200407135416.24093-3-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx> Reviewed-by: Baoquan He <bhe@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/memory_hotplug.h | 7 -- mm/memory_hotplug.c | 75 ------------------------------- 2 files changed, 82 deletions(-) --- a/include/linux/memory_hotplug.h~mm-memory_hotplug-remove-is_mem_section_removable +++ a/include/linux/memory_hotplug.h @@ -314,19 +314,12 @@ static inline void pgdat_resize_init(str #ifdef CONFIG_MEMORY_HOTREMOVE -extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages); extern void try_offline_node(int nid); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); extern int remove_memory(int nid, u64 start, u64 size); extern void __remove_memory(int nid, u64 start, u64 size); #else -static inline bool is_mem_section_removable(unsigned long pfn, - unsigned long nr_pages) -{ - return false; -} - static inline void try_offline_node(int nid) {} static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages) --- a/mm/memory_hotplug.c~mm-memory_hotplug-remove-is_mem_section_removable +++ a/mm/memory_hotplug.c @@ -1114,81 +1114,6 @@ EXPORT_SYMBOL_GPL(add_memory); #ifdef CONFIG_MEMORY_HOTREMOVE /* - * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy - * set and the size of the free page is given by page_order(). Using this, - * the function determines if the pageblock contains only free pages. - * Due to buddy contraints, a free page at least the size of a pageblock will - * be located at the start of the pageblock - */ -static inline int pageblock_free(struct page *page) -{ - return PageBuddy(page) && page_order(page) >= pageblock_order; -} - -/* Return the pfn of the start of the next active pageblock after a given pfn */ -static unsigned long next_active_pageblock(unsigned long pfn) -{ - struct page *page = pfn_to_page(pfn); - - /* Ensure the starting page is pageblock-aligned */ - BUG_ON(pfn & (pageblock_nr_pages - 1)); - - /* If the entire pageblock is free, move to the end of free page */ - if (pageblock_free(page)) { - int order; - /* be careful. we don't have locks, page_order can be changed.*/ - order = page_order(page); - if ((order < MAX_ORDER) && (order >= pageblock_order)) - return pfn + (1 << order); - } - - return pfn + pageblock_nr_pages; -} - -static bool is_pageblock_removable_nolock(unsigned long pfn) -{ - struct page *page = pfn_to_page(pfn); - struct zone *zone; - - /* - * We have to be careful here because we are iterating over memory - * sections which are not zone aware so we might end up outside of - * the zone but still within the section. - * We have to take care about the node as well. If the node is offline - * its NODE_DATA will be NULL - see page_zone. - */ - if (!node_online(page_to_nid(page))) - return false; - - zone = page_zone(page); - pfn = page_to_pfn(page); - if (!zone_spans_pfn(zone, pfn)) - return false; - - return !has_unmovable_pages(zone, page, MIGRATE_MOVABLE, - MEMORY_OFFLINE); -} - -/* Checks if this range of memory is likely to be hot-removable. */ -bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) -{ - unsigned long end_pfn, pfn; - - end_pfn = min(start_pfn + nr_pages, - zone_end_pfn(page_zone(pfn_to_page(start_pfn)))); - - /* Check the starting page of each pageblock within the range */ - for (pfn = start_pfn; pfn < end_pfn; pfn = next_active_pageblock(pfn)) { - if (!is_pageblock_removable_nolock(pfn)) - return false; - cond_resched(); - } - - /* All pageblocks in the memory block are likely to be hot-removable */ - return true; -} - -/* * Confirm all pages in a range [start, end) belong to the same zone (skipping * memory holes). When true, return the zone. */ _