On Fri, Mar 18, 2022 at 06:07:17PM +0800, Muchun Song wrote: You can add Suggested-by tag here. > Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> > --- > Kbuild | 12 ++++++++++++ > fs/Kconfig | 2 +- > include/linux/mm_types.h | 2 ++ > mm/Kconfig | 3 +++ > mm/hugetlb_vmemmap.c | 6 ------ > mm/struct_page_size.c | 19 +++++++++++++++++++ > scripts/check_struct_page_po2.sh | 11 +++++++++++ > 7 files changed, 48 insertions(+), 7 deletions(-) > create mode 100644 mm/struct_page_size.c > create mode 100755 scripts/check_struct_page_po2.sh > > diff --git a/Kbuild b/Kbuild > index fa441b98c9f6..6bb97d348d62 100644 > --- a/Kbuild > +++ b/Kbuild > @@ -14,6 +14,18 @@ $(bounds-file): kernel/bounds.s FORCE > $(call filechk,offsets,__LINUX_BOUNDS_H__) > > ##### > +# Generate struct_page_size.h. Must follows bounds.h. > + > +struct_page_size-file := include/generated/struct_page_size.h > + > +always-y := $(struct_page_size-file) > +targets := mm/struct_page_size.s > + > +$(struct_page_size-file): mm/struct_page_size.s FORCE > + $(call filechk,offsets,__LINUX_STRUCT_PAGE_SIZE_H__) > + $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig > + > +##### Shouldn't this go into mm/Makefile instead? > diff --git a/mm/Kconfig b/mm/Kconfig > index 034d87953600..9314bd34f49e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -2,6 +2,9 @@ > > menu "Memory Management options" > > +config STRUCT_PAGE_SIZE_IS_POWER_OF_2 > + def_bool $(success,test "$(shell, $(srctree)/scripts/check_struct_page_po2.sh)" = 1) > + > config SELECT_MEMORY_MODEL > def_bool y > depends on ARCH_SELECT_MEMORY_MODEL > new file mode 100755 > index 000000000000..9547ad3aca05 > --- /dev/null > +++ b/scripts/check_struct_page_po2.sh > @@ -0,0 +1,11 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > +# > +# Check if the size of "struct page" is power of 2 > + > +file="include/generated/struct_page_size.h" > +if [ ! -f "$file" ]; then Does this really work if one is workig off of a very clean build like make mrproper and then make menuconfig or or mrproper followed by a defconfig file ? Have you tried it for both cases po2 and npo2? Because isn't include/generated/struct_page_size.h generated? At which point does it get generated and why would the condition hole true that the file exists at a new 'make menuconfig' time? Luis
