The purpose of introducing HUGETLB_PAGE_FREE_VMEMMAP is to configure whether to enable the feature of freeing unused vmemmap associated with HugeTLB pages. Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- fs/Kconfig | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/fs/Kconfig b/fs/Kconfig index 976e8b9033c4..61e9c08096ca 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -245,6 +245,21 @@ config HUGETLBFS config HUGETLB_PAGE def_bool HUGETLBFS +config HUGETLB_PAGE_FREE_VMEMMAP + bool "Free unused vmemmap associated with HugeTLB pages" + default n + depends on HUGETLB_PAGE + depends on SPARSEMEM_VMEMMAP + depends on HAVE_BOOTMEM_INFO_NODE + help + There are many struct page structure associated with each HugeTLB + page. But we only use a few struct page structure. In this case, + it waste some memory. It is better to free the unused struct page + structures to buddy system which can save some memory. For + architectures that support it, say Y here. + + If unsure, say N. + config MEMFD_CREATE def_bool TMPFS || HUGETLBFS -- 2.20.1
