This series is based on next-20220407. This series amis to add hugetlb_optimize_vmemmap sysctl to enable or disable the feature of optimizing vmemmap pages associated with HugeTLB pages. v8: - Fix compilation (scripts/selinux/mdp/mdp.c) error when CONFIG_SECURITY_SELINUX is selected. v7: - Fix circular dependency issue reported by kernel test robot. - Introduce CONFIG_HUGETLB_PAGE_HAS_OPTIMIZE_VMEMMAP instead of STRUCT_PAGE_SIZE_IS_POWER_OF_2. - Add more comments into vm.rst to explain hugetlb_optimize_vmemmap (Andrew). - Drop the patch "sysctl: allow to set extra1 to SYSCTL_ONE". - Add a new patch "use kstrtobool for hugetlb_vmemmap param parsing". - Reuse static_key's refcount to count the number of HugeTLB pages with vmemmap pages optimized to simplify the lock scheme. v6: - Remove "make syncconfig" from Kbuild. v5: - Fix not working properly if one is workig off of a very clean build reported by Luis Chamberlain. - Add Suggested-by for Luis Chamberlain. v4: - Introduce STRUCT_PAGE_SIZE_IS_POWER_OF_2 inspired by Luis. v3: - Add pr_warn_once() (Mike). - Handle the transition from enabling to disabling (Luis) v2: - Fix compilation when !CONFIG_MHP_MEMMAP_ON_MEMORY reported by kernel test robot <lkp@xxxxxxxxx>. - Move sysctl code from kernel/sysctl.c to mm/hugetlb_vmemmap.c. Muchun Song (4): mm: hugetlb_vmemmap: introduce CONFIG_HUGETLB_PAGE_HAS_OPTIMIZE_VMEMMAP mm: memory_hotplug: override memmap_on_memory when hugetlb_free_vmemmap=on mm: hugetlb_vmemmap: use kstrtobool for hugetlb_vmemmap param parsing mm: hugetlb_vmemmap: add hugetlb_optimize_vmemmap sysctl Documentation/admin-guide/kernel-parameters.txt | 6 +- Documentation/admin-guide/sysctl/vm.rst | 27 +++++++ Kbuild | 19 +++++ arch/x86/mm/init_64.c | 2 +- include/linux/hugetlb.h | 2 +- include/linux/kconfig.h | 4 + include/linux/memory_hotplug.h | 9 +++ include/linux/mm.h | 2 +- include/linux/page-flags.h | 2 +- kernel/autoconf_ext.c | 26 ++++++ mm/hugetlb_vmemmap.c | 102 ++++++++++++++++++++---- mm/hugetlb_vmemmap.h | 8 +- mm/memory_hotplug.c | 27 +++++-- mm/sparse-vmemmap.c | 4 +- scripts/mod/Makefile | 2 + 15 files changed, 207 insertions(+), 35 deletions(-) create mode 100644 kernel/autoconf_ext.c -- 2.11.0