Commit 3f3eaf96 authored by Liu Shixin's avatar Liu Shixin Committed by Zheng Zengkai
Browse files

mm/dynamic_hugetlb: only support to merge 2M dynamicly 

hulk inclusion
category: bugfix
bugzilla: 46904 https://gitee.com/openeuler/kernel/issues/I4Y0XO



--------------------------------

We do not support dynamic combination of 1G hugepages dynamicly as this can
result in a significant performance loss. We suggest to configure the number of
hugepages immediately after creating a dynamic hugetlb pool rather than modify
them dynamicly while some processes are runing.

Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 687fb2b1

mm/dynamic_hugetlb.c

+14 −11
Original line number Diff line number Diff line
@@ -938,6 +938,8 @@ static ssize_t update_reserved_pages(struct mem_cgroup *memcg, char *buf, int hp 
			if (hpool_split_page(hpool, hpages_pool_idx - 1))

				break;

		}

		/* Currently, only merging 2M hugepages is supported */

		if (hpages_pool_idx == HUGE_PAGES_POOL_2M) {

			/*

			 * First try to merge pages without migration, If this can not meet

			 * the requirements, then try to merge pages with migration.
@@ -950,6 +952,7 @@ static ssize_t update_reserved_pages(struct mem_cgroup *memcg, char *buf, int hp 
				if (hpool_merge_page(hpool, hpages_pool_idx, true))

					break;

			}

		}

		delta = min(nr_pages - hpages_pool->nr_huge_pages, hpages_pool->free_normal_pages);

		hpages_pool->nr_huge_pages += delta;

		hpages_pool->free_huge_pages += delta;