When testing the gigantic page whose order is too large for the buddy allocator, the libhugetlbfs test case "counter.sh" will fail. The failure is caused by: 1) kernel fails to allocate a gigantic page for the surplus case. And the gather_surplus_pages() will return NULL in the end. 2) The condition checks for "over-commit" is wrong. This patch adds code to allocate the gigantic page in the __alloc_huge_page(). After this patch, gather_surplus_pages() can return a gigantic page for the surplus case. This patch changes the condition checks for: return_unused_surplus_pages() nr_overcommit_hugepages_store() hugetlb_overcommit_handler() This patch also set @nid with proper value when NUMA_NO_NODE is passed to alloc_gigantic_page(). After this patch, the counter.sh can pass for the gigantic page. Acked-by: Steve Capper <steve.capper@xxxxxxx> Signed-off-by: Huang Shijie <shijie.huang@xxxxxxx> --- 1. fix the wrong check in hugetlb_overcommit_handler(); 2. try to fix the s390 issue. --- mm/hugetlb.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 9fdfc24..5dbfd62 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1095,6 +1095,9 @@ static struct page *alloc_gigantic_page(int nid, unsigned int order) unsigned long ret, pfn, flags; struct zone *z; + if (nid == NUMA_NO_NODE) + nid = numa_mem_id(); + z = NODE_DATA(nid)->node_zones; for (; z - NODE_DATA(nid)->node_zones < MAX_NR_ZONES; z++) { spin_lock_irqsave(&z->lock, flags); @@ -1578,7 +1581,7 @@ static struct page *__alloc_huge_page(struct hstate *h, struct page *page; unsigned int r_nid; - if (hstate_is_gigantic(h)) + if (hstate_is_gigantic(h) && !gigantic_page_supported()) return NULL; /* @@ -1623,7 +1626,13 @@ static struct page *__alloc_huge_page(struct hstate *h, } spin_unlock(&hugetlb_lock); - page = __hugetlb_alloc_buddy_huge_page(h, vma, addr, nid); + if (hstate_is_gigantic(h)) { + page = alloc_gigantic_page(nid, huge_page_order(h)); + if (page) + prep_compound_gigantic_page(page, huge_page_order(h)); + } else { + page = __hugetlb_alloc_buddy_huge_page(h, vma, addr, nid); + } spin_lock(&hugetlb_lock); if (page) { @@ -1790,8 +1799,7 @@ static void return_unused_surplus_pages(struct hstate *h, /* Uncommit the reservation */ h->resv_huge_pages -= unused_resv_pages; - /* Cannot return gigantic pages currently */ - if (hstate_is_gigantic(h)) + if (hstate_is_gigantic(h) && !gigantic_page_supported()) return; nr_pages = min(unused_resv_pages, h->surplus_huge_pages); @@ -2443,7 +2451,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, unsigned long input; struct hstate *h = kobj_to_hstate(kobj, NULL); - if (hstate_is_gigantic(h)) + if (hstate_is_gigantic(h) && !gigantic_page_supported()) return -EINVAL; err = kstrtoul(buf, 10, &input); @@ -2884,7 +2892,7 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write, tmp = h->nr_overcommit_huge_pages; - if (write && hstate_is_gigantic(h)) + if (write && hstate_is_gigantic(h) && !gigantic_page_supported()) return -EINVAL; table->data = &tmp; -- 2.1.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>