diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 716465ae57aa78eff121779cd45ada7fc63b2fbd..10de25cf1f99ae33df5a9834a9f40a17e631f9a9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -40,6 +40,11 @@ int hugepages_treat_as_movable; int hugetlb_max_hstate __read_mostly; unsigned int default_hstate_idx; struct hstate hstates[HUGE_MAX_HSTATE]; +/* + * Minimum page order among possible hugepage sizes, set to a proper value + * at boot time. + */ +static unsigned int minimum_order __read_mostly = UINT_MAX; __initdata LIST_HEAD(huge_boot_pages); @@ -1188,19 +1193,13 @@ static void dissolve_free_huge_page(struct page *page) */ void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) { - unsigned int order = 8 * sizeof(void *); unsigned long pfn; - struct hstate *h; if (!hugepages_supported()) return; - /* Set scan step to minimum hugepage size */ - for_each_hstate(h) - if (order > huge_page_order(h)) - order = huge_page_order(h); - VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << order)); - for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order) + VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << minimum_order)); + for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order) dissolve_free_huge_page(pfn_to_page(pfn)); } @@ -1627,10 +1626,14 @@ static void __init hugetlb_init_hstates(void) struct hstate *h; for_each_hstate(h) { + if (minimum_order > huge_page_order(h)) + minimum_order = huge_page_order(h); + /* oversize hugepages were init'ed in early boot */ if (!hstate_is_gigantic(h)) hugetlb_hstate_alloc_pages(h); } + VM_BUG_ON(minimum_order == UINT_MAX); } static char * __init memfmt(char *buf, unsigned long n)