From: Feiyang Chen <chenfeiyang@xxxxxxxxxxx> 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, so just select ARCH_WANT_HUGETLB_PAGE_ OPTIMIZE_VMEMMAP is enough to enable this feature for LoongArch. To avoid the following build error on LoongArch we should include linux/ static_key.h in page-flags.h. This is straightforward but the build error is implicitly a LoongArch-specific problem, because ARM64 and X86 have already include static_key.h from their arch-specific core headers. In file included from ./include/linux/mmzone.h:22, from ./include/linux/gfp.h:6, from ./include/linux/mm.h:7, from arch/loongarch/kernel/asm-offsets.c:9: ./include/linux/page-flags.h:208:1: warning: data definition has no type or storage class 208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON, | ^~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/page-flags.h:208:1: error: type defaults to 'int' in declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int] ./include/linux/page-flags.h:209:26: warning: parameter names (without types) in function declaration 209 | hugetlb_optimize_vmemmap_key); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/page-flags.h: In function 'hugetlb_optimize_vmemmap_enabled': ./include/linux/page-flags.h:213:16: error: implicit declaration of function 'static_branch_maybe' [-Werror=implicit-function-declaration] 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON, | ^~~~~~~~~~~~~~~~~~~ ./include/linux/page-flags.h:213:36: error: 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON' undeclared (first use in this function); did you mean 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP'? 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP ./include/linux/page-flags.h:213:36: note: each undeclared identifier is reported only once for each function it appears in ./include/linux/page-flags.h:214:37: error: 'hugetlb_optimize_vmemmap_key' undeclared (first use in this function); did you mean 'hugetlb_optimize_vmemmap_enabled'? 214 | &hugetlb_optimize_vmemmap_key); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ | hugetlb_optimize_vmemmap_enabled Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx> Signed-off-by: Feiyang Chen <chenfeiyang@xxxxxxxxxxx> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> --- arch/loongarch/Kconfig | 1 + include/linux/page-flags.h | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 6f7fa0c0ca08..0a6ef613124c 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -52,6 +52,7 @@ config LOONGARCH select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT + select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP select ARCH_WANT_LD_ORPHAN_WARN select ARCH_WANTS_NO_INSTR select BUILDTIME_TABLE_SORT diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 0b0ae5084e60..1aafdc73e399 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -9,6 +9,7 @@ #include <linux/types.h> #include <linux/bug.h> #include <linux/mmdebug.h> +#include <linux/static_key.h> #ifndef __GENERATING_BOUNDS_H #include <linux/mm_types.h> #include <generated/bounds.h> -- 2.31.1
