linux/Kbuild
Masahiro Yamada b10fdeea8c kbuild: check sha1sum just once for each atomic header
It is unneeded to check the sha1sum every time.

Create the timestamp files to manage it.

Add '.' to clean-dirs because 'make clean' must visit ./Kbuild to
clean up the timestamp files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-09-29 04:40:14 +09:00

75 lines
1.9 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
#
# Kbuild for top-level directory of the kernel
# Prepare global headers and check sanity before descending into sub-directories
# ---------------------------------------------------------------------------
# Generate bounds.h
bounds-file := include/generated/bounds.h
targets := kernel/bounds.s
$(bounds-file): kernel/bounds.s FORCE
$(call filechk,offsets,__LINUX_BOUNDS_H__)
# Generate timeconst.h
timeconst-file := include/generated/timeconst.h
filechk_gentimeconst = echo $(CONFIG_HZ) | bc -q $<
$(timeconst-file): kernel/time/timeconst.bc FORCE
$(call filechk,gentimeconst)
# Generate asm-offsets.h
offsets-file := include/generated/asm-offsets.h
targets += arch/$(SRCARCH)/kernel/asm-offsets.s
arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
$(call filechk,offsets,__ASM_OFFSETS_H__)
# Check for missing system calls
quiet_cmd_syscalls = CALL $<
cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
PHONY += missing-syscalls
missing-syscalls: scripts/checksyscalls.sh $(offsets-file)
$(call cmd,syscalls)
# Check the manual modification of atomic headers
quiet_cmd_check_sha1 = CHKSHA1 $<
cmd_check_sha1 = \
if ! command -v sha1sum >/dev/null; then \
echo "warning: cannot check the header due to sha1sum missing"; \
exit 0; \
fi; \
if [ "$$(sed -n '$$s:// ::p' $<)" != \
"$$(sed '$$d' $< | sha1sum | sed 's/ .*//')" ]; then \
echo "error: $< has been modified." >&2; \
exit 1; \
fi; \
touch $@
atomic-checks += $(addprefix $(obj)/.checked-, \
atomic-arch-fallback.h \
atomic-instrumented.h \
atomic-long.h)
targets += $(atomic-checks)
$(atomic-checks): $(obj)/.checked-%: include/linux/atomic/% FORCE
$(call if_changed,check_sha1)
# A phony target that depends on all the preparation targets
PHONY += prepare
prepare: $(offsets-file) missing-syscalls $(atomic-checks)
@: