On 9/15/20 5:59 AM, Muchun Song wrote: > 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 structures > + page. But we only use a few struct page structure. In this case, structures. > + it waste some memory. It is better to free the unused struct page it wastes > + 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 > > -- ~Randy
