From: Baoquan He <bhe@xxxxxxxxxx> Subject: mm/sparse.c: use kvmalloc/kvfree to alloc/free memmap for the classic sparse This change makes populate_section_memmap()/depopulate_section_memmap much simpler. Link: http://lkml.kernel.org/r/20200316125450.GG3486@MiWiFi-R3L-srv Signed-off-by: Baoquan He <bhe@xxxxxxxxxx> Suggested-by: Michal Hocko <mhocko@xxxxxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx> Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/sparse.c | 27 +++------------------------ 1 file changed, 3 insertions(+), 24 deletions(-) --- a/mm/sparse.c~mm-sparsec-use-kvmalloc-kvfree-to-alloc-free-memmap-for-the-classic-sparse +++ a/mm/sparse.c @@ -664,35 +664,14 @@ static void free_map_bootmem(struct page struct page * __meminit populate_section_memmap(unsigned long pfn, unsigned long nr_pages, int nid, struct vmem_altmap *altmap) { - struct page *page, *ret; - unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION; - - page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size)); - if (page) - goto got_map_page; - - ret = vmalloc(memmap_size); - if (ret) - goto got_map_ptr; - - return NULL; -got_map_page: - ret = (struct page *)pfn_to_kaddr(page_to_pfn(page)); -got_map_ptr: - - return ret; + return kvmalloc(array_size(sizeof(struct page), + PAGES_PER_SECTION), GFP_KERNEL); } static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages, struct vmem_altmap *altmap) { - struct page *memmap = pfn_to_page(pfn); - - if (is_vmalloc_addr(memmap)) - vfree(memmap); - else - free_pages((unsigned long)memmap, - get_order(sizeof(struct page) * PAGES_PER_SECTION)); + kvfree(pfn_to_page(pfn)); } static void free_map_bootmem(struct page *memmap) _
