On Thu, Mar 31, 2022 at 4:42 PM David Hildenbrand <david@xxxxxxxxxx> wrote: > > On 31.03.22 08:56, Muchun Song wrote: > > The feature of minimizing overhead of struct page associated with each > > HugeTLB page is implemented on x86_64, however, the infrastructure of > > this feature is already there, we could easily enable it for other > > architectures. Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other > > architectures to be easily enabled. Just select this config if they > > want to enable this feature. > > > > Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> > > --- > > arch/x86/Kconfig | 1 + > > fs/Kconfig | 10 +++++++++- > > 2 files changed, 10 insertions(+), 1 deletion(-) > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index 9f5bd41bf660..e69d42528542 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -119,6 +119,7 @@ config X86 > > select ARCH_WANTS_DYNAMIC_TASK_STRUCT > > select ARCH_WANTS_NO_INSTR > > select ARCH_WANT_HUGE_PMD_SHARE > > + select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP if X86_64 > > select ARCH_WANT_LD_ORPHAN_WARN > > select ARCH_WANTS_THP_SWAP if X86_64 > > select ARCH_HAS_PARANOID_L1D_FLUSH > > diff --git a/fs/Kconfig b/fs/Kconfig > > index 6c7dc1387beb..f6db2af33738 100644 > > --- a/fs/Kconfig > > +++ b/fs/Kconfig > > @@ -245,9 +245,17 @@ config HUGETLBFS > > config HUGETLB_PAGE > > def_bool HUGETLBFS > > > > +# > > +# Select this config option from the architecture Kconfig, if it is preferred > > +# to enable the feature of minimizing overhead of struct page associated with > > +# each HugeTLB page. > > +# > > +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP > > + bool > > + > > config HUGETLB_PAGE_FREE_VMEMMAP > > def_bool HUGETLB_PAGE > > - depends on X86_64 > > + depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP > > depends on SPARSEMEM_VMEMMAP > > > > config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON > > > I think something like "HUGETLB_OPTIMIZE_VMEMMAP" might be more > expressive, but that would imply renaming the existing config knob. > How about doing a full code cleanup in a separate series in the future?
