linux-stable/Kbuild
Kieran Bingham f197d75fca scripts/gdb: provide linux constants
Some macro's and defines are needed when parsing memory, and without
compiling the kernel as -g3 they are not available in the debug-symbols.

We use the pre-processor here to extract constants to a dedicated module
for the linux debugger extensions

Top level Kbuild is used to call in and generate the constants file,
while maintaining dependencies on autogenerated files in
include/generated

Link: http://lkml.kernel.org/r/bc3df9c25f57ea72177c066a51a446fc19e2c27f.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00

110 lines
2.8 KiB
Makefile

#
# Kbuild for top-level directory of the kernel
# This file takes care of the following:
# 1) Generate bounds.h
# 2) Generate timeconst.h
# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
# 4) Check for missing system calls
# 5) Generate constants.py (may need bounds.h)
# Default sed regexp - multiline due to syntax constraints
define sed-y
"/^->/{s:->#\(.*\):/* \1 */:; \
s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
s:->::; p;}"
endef
# Use filechk to avoid rebuilds when a header changes, but the resulting file
# does not
define filechk_offsets
(set -e; \
echo "#ifndef $2"; \
echo "#define $2"; \
echo "/*"; \
echo " * DO NOT MODIFY."; \
echo " *"; \
echo " * This file was generated by Kbuild"; \
echo " */"; \
echo ""; \
sed -ne $(sed-y); \
echo ""; \
echo "#endif" )
endef
#####
# 1) Generate bounds.h
bounds-file := include/generated/bounds.h
always := $(bounds-file)
targets := kernel/bounds.s
# We use internal kbuild rules to avoid the "is up to date" message from make
kernel/bounds.s: kernel/bounds.c FORCE
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)
$(obj)/$(bounds-file): kernel/bounds.s FORCE
$(call filechk,offsets,__LINUX_BOUNDS_H__)
#####
# 2) Generate timeconst.h
timeconst-file := include/generated/timeconst.h
targets += $(timeconst-file)
quiet_cmd_gentimeconst = GEN $@
define cmd_gentimeconst
(echo $(CONFIG_HZ) | bc -q $< ) > $@
endef
define filechk_gentimeconst
(echo $(CONFIG_HZ) | bc -q $< )
endef
$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
$(call filechk,gentimeconst)
#####
# 3) Generate asm-offsets.h
#
offsets-file := include/generated/asm-offsets.h
always += $(offsets-file)
targets += arch/$(SRCARCH)/kernel/asm-offsets.s
# We use internal kbuild rules to avoid the "is up to date" message from make
arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
$(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)
$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
$(call filechk,offsets,__ASM_OFFSETS_H__)
#####
# 4) Check for missing system calls
#
always += missing-syscalls
targets += missing-syscalls
quiet_cmd_syscalls = CALL $<
cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
$(call cmd,syscalls)
#####
# 5) Generate constants for Python GDB integration
#
extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
@$(MAKE) $(build)=scripts/gdb/linux $@
# Keep these three files during make clean
no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)