Masahiro Yamada (7):
kbuild: clear LDFLAGS in the top Makefile
kbuild: remove wrong 'touch' in adjust_autoksyms.sh
kbuild: move 'scripts' target below
kbuild: restore touching autoksyms.h to the top Makefile
kbuild: move CONFIG_TRIM_UNUSED_KSYMS code unneeded for external
module
kbuild: move include/config/ksym/* to include/ksym/*
kbuild: link vmlinux only once for CONFIG_TRIM_UNUSED_KSYMS
.gitignore | 1 +
Makefile | 66 ++++++++++++++++++++++-----------------------
scripts/Kbuild.include | 2 +-
scripts/adjust_autoksyms.sh | 5 +---
scripts/basic/fixdep.c | 8 +++---
scripts/kconfig/Makefile | 2 --
6 files changed, 39 insertions(+), 45 deletions(-)
--
2.7.4
If CONFIG_TRIM_UNUSED_KSYMS is enabled and the kernel is built from
a pristine state, the vmlinux is linked twice.
[1] A user runs "make"
[2] First build with empty autoksyms.h
[3] adjust_autoksyms.sh updates autoksyms.h and recurses "make vmlinux"
--------(begin sub-make)--------
[4] Second build with new autoksyms.h
[5] link-vmlinux.sh is invoked because "vmlinux" is missing
---------(end sub-make)---------
[6] link-vmlinux.sh is invoked again despite "vmlinux" is up-to-date.
The reason of [6] is probably because Make already decided to update
"vmlinux" at the time of [2] because "vmlinux" was missing when Make
built up the dependency graph.
Because 'if_changed' is implemented based on '$?', this issue can be
narrowed down to how Make handles '$?'.
You can test it with the following simple code:
[Test Makefile]
A: B
cp B A
@echo newer prerequisite: $?
B: C
cp C B
touch A
[Result]
$ rm -f A B
$ touch C
$ make
cp C B
touch A
cp B A
newer prerequisite: B
Here, 'A' has been touched in the recipe of 'B'. So, the dependency
'A: B' has already been met before the recipe of 'A' is executed.
However, Make does not notice the fact that the recipe of 'B' also
updates 'A' as a side-effect.
The situation is similar in this case; 'vmlinux' has actually been
updated in the 'vmlinux_prereq' target. Make cannot predict this, so
judges 'vmlinux' is old.
link-vmlinus.sh is costly, so it is better to not run it when unneeded.
Split CONFIG_TRIM_UNUSED_KSYMS recursion to a dedicated target.
The reason of commit 2441e78b1919 ("kbuild: better abstract vmlinux
sequential prerequisites") was to cater to CONFIG_BUILD_DOCSRC, but
it was later removed by commit 184892925118 ("samples: move blackfin
gptimers-example from Documentation").
Signed-off-by: Masahiro Yamada <[email protected]>
---
Changes in v2:
- Discard my wrong change to adjust_autoksyms.sh
- Add more commit log to explain how Make is working
Makefile | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/Makefile b/Makefile
index 5fee703..3e871d2 100644
--- a/Makefile
+++ b/Makefile
@@ -998,21 +998,11 @@ export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Doc
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
-# Include targets which we want to execute sequentially if the rest of the
-# kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
-# evaluated more than once.
-PHONY += vmlinux_prereq
-vmlinux_prereq: $(vmlinux-deps) FORCE
-ifdef CONFIG_HEADERS_CHECK
- $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
-endif
-ifdef CONFIG_GDB_SCRIPTS
- $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
-endif
-ifdef CONFIG_TRIM_UNUSED_KSYMS
- $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
+# Recurse until adjust_autoksyms.sh is satisfied
+PHONY += autoksyms_recursive
+autoksyms_recursive: $(vmlinux-deps)
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
"$(MAKE) -f $(srctree)/Makefile vmlinux"
-endif
# For the kernel to actually contain only the needed exported symbols,
# we have to build modules as well to determine what those symbols are.
@@ -1034,7 +1024,13 @@ cmd_link-vmlinux = \
$(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
-vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
+vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
+ifdef CONFIG_HEADERS_CHECK
+ $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
+endif
+ifdef CONFIG_GDB_SCRIPTS
+ $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
+endif
+$(call if_changed,link-vmlinux)
# Build samples along the rest of the kernel
--
2.7.4
The idea of using fixdep was inspired by Kconfig, but autoksyms
belongs to a different group. So, I want move those touched files
under include/config/ksym/ to include/ksym/.
The directory include/ksym/ can be removed by "make clean" because
it is meaningless for the external module building.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Changes in v2:
- Rebase on linux-next
(resolve a conflict to https://patchwork.kernel.org/patch/10204653/)
.gitignore | 1 +
Makefile | 2 +-
scripts/Kbuild.include | 2 +-
scripts/adjust_autoksyms.sh | 2 +-
scripts/basic/fixdep.c | 8 ++++----
5 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/.gitignore b/.gitignore
index 1be78fd..85bcc26 100644
--- a/.gitignore
+++ b/.gitignore
@@ -87,6 +87,7 @@ modules.builtin
#
include/config
include/generated
+include/ksym
arch/*/include/generated
# stgit generated dirs
diff --git a/Makefile b/Makefile
index ef42adb..5fee703 100644
--- a/Makefile
+++ b/Makefile
@@ -1338,7 +1338,7 @@ endif # CONFIG_MODULES
# make distclean Remove editor backup files, patch leftover files and the like
# Directories & files removed with 'make clean'
-CLEAN_DIRS += $(MODVERDIR)
+CLEAN_DIRS += $(MODVERDIR) include/ksym
# Directories & files removed with 'make mrproper'
MRPROPER_DIRS += include/config usr/include include/generated \
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index f9c2f07..cce31ee 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -366,7 +366,7 @@ ksym_dep_filter = \
$(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \
boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \
*) echo "Don't know how to preprocess $(1)" >&2; false ;; \
- esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/KSYM_\1/p'
+ esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/_\1/p'
cmd_and_fixdep = \
$(echo-cmd) $(cmd_$(1)); \
diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh
index e0dd0d5..f11cae6 100755
--- a/scripts/adjust_autoksyms.sh
+++ b/scripts/adjust_autoksyms.sh
@@ -80,7 +80,7 @@ sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u |
sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | tr "A-Z_" "a-z/" |
while read sympath; do
if [ -z "$sympath" ]; then continue; fi
- depfile="include/config/ksym/${sympath}.h"
+ depfile="include/ksym/${sympath}.h"
mkdir -p "$(dirname "$depfile")"
touch "$depfile"
echo $((count += 1))
diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c
index 449b68c..f387538 100644
--- a/scripts/basic/fixdep.c
+++ b/scripts/basic/fixdep.c
@@ -113,11 +113,11 @@ static void usage(void)
/*
* Print out a dependency path from a symbol name
*/
-static void print_config(const char *m, int slen)
+static void print_dep(const char *m, int slen, const char *dir)
{
int c, i;
- printf(" $(wildcard include/config/");
+ printf(" $(wildcard %s/", dir);
for (i = 0; i < slen; i++) {
c = m[i];
if (c == '_')
@@ -140,7 +140,7 @@ static void do_extra_deps(void)
fprintf(stderr, "fixdep: bad data on stdin\n");
exit(1);
}
- print_config(buf, len - 1);
+ print_dep(buf, len - 1, "include/ksym");
}
}
@@ -208,7 +208,7 @@ static void use_config(const char *m, int slen)
return;
define_config(m, slen, hash);
- print_config(m, slen);
+ print_dep(m, slen, "include/config");
}
/* test if s ends in sub */
--
2.7.4
Commit d3fc425e819b ("kbuild: make sure autoksyms.h exists early")
moved the code that touches autoksyms.h to scripts/kconfig/Makefile
with obscure reason.
From Nicolas' comment [1], he did not seem to be sure about the root
cause.
I guess I figured it out, so here is a fix-up I think is more correct.
According to the error log in the original post [2], the build failed
in scripts/mod/devicetable-offsets.c
scripts/mod/Makefile is descended from scripts/Makefile, which is
invoked from the top-level Makefile by the 'scripts' target.
To build vmlinux and/or modules, Kbuild descend into $(vmlinux-dirs).
This depends on 'prepare' and 'scripts' as follows:
$(vmlinux-dirs): prepare scripts
Because there is no dependency between 'prepare' and 'scripts', the
parallel building can run them simultaneously.
'prepare' depends on 'prepare1', which touched autoksyms.h, whereas
'scripts' descends into script/, then scripts/mod/, which needs
<generated/autoksyms.h> if CONFIG_TRIM_UNUSED_KSYMS. It was the
reason of the race.
I am not happy to have unrelated code in the Kconfig Makefile, so
getting it back to the top Makefile.
I removed the standalone test target because I want to use it to
create an empty autoksyms.h file. Here is a little improvement;
unnecessary autoksyms.h is not created when CONFIG_TRIM_UNUSED_KSYMS
is disabled.
[1] https://lkml.org/lkml/2016/11/30/734
[2] https://lkml.org/lkml/2016/11/30/531
Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
---
Changes in v2: None
Makefile | 12 +++++++-----
scripts/kconfig/Makefile | 2 --
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/Makefile b/Makefile
index f8e9e12..0a3895c 100644
--- a/Makefile
+++ b/Makefile
@@ -1021,9 +1021,11 @@ ifdef CONFIG_TRIM_UNUSED_KSYMS
"$(MAKE) -f $(srctree)/Makefile vmlinux"
endif
-# standalone target for easier testing
-include/generated/autoksyms.h: FORCE
- $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
+autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
+
+$(autoksyms_h):
+ $(Q)mkdir -p $(dir $@)
+ $(Q)touch $@
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
@@ -1067,7 +1069,7 @@ include/config/kernel.release: include/config/auto.conf FORCE
# in parallel
PHONY += scripts
scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
- asm-generic gcc-plugins autoksyms
+ asm-generic gcc-plugins $(autoksyms_h)
$(Q)$(MAKE) $(build)=$(@)
# Things we need to do before we recursively start building the kernel
@@ -1097,7 +1099,7 @@ endif
# that need to depend on updated CONFIG_* values can be checked here.
prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
-prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
+prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
include/config/auto.conf
$(cmd_crmodverdir)
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 78c96aa..f9bdd02 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -38,8 +38,6 @@ nconfig: $(obj)/nconf
# for external use.
syncconfig: $(obj)/conf
$(Q)mkdir -p include/config include/generated
- $(Q)test -e include/generated/autoksyms.h || \
- touch include/generated/autoksyms.h
$< $(silent) --$@ $(Kconfig)
localyesconfig localmodconfig: $(obj)/conf
--
2.7.4
Currently LDFLAGS is not cleared, so same flags are accumulated in
LDFLAGS when the top Makefile is recursively invoked.
I found unneeded rebuild for ARCH=arm64 when CONFIG_TRIM_UNUSED_KSYMS
is enabled. If include/generated/autoksyms.h is updated, the top
Makefile is recursively invoked, then arch/arm64/Makefile adds one
more '-maarch64linux'. Due to the command line change, modules are
rebuilt needlessly.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Changes in v2: None
Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/Makefile b/Makefile
index d9bb6dd6..ac8755d 100644
--- a/Makefile
+++ b/Makefile
@@ -437,6 +437,7 @@ KBUILD_CFLAGS_KERNEL :=
KBUILD_AFLAGS_MODULE := -DMODULE
KBUILD_CFLAGS_MODULE := -DMODULE
KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
+LDFLAGS :=
GCC_PLUGINS_CFLAGS :=
export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
--
2.7.4
The comment mentions it creates autoksyms.h in case it is missing,
but the actual code touches it when it does exists.
The build system creates it anyway because <linux/export.h> and
<asm-generic/export.h> need it.
The code would not have worked as intended, and people have not
noticed it. This is a proof that we can simply remove it.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Changes in v2:
- Remove the code instead of fixing it
scripts/adjust_autoksyms.sh | 3 ---
1 file changed, 3 deletions(-)
diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh
index a162258..e0dd0d5 100755
--- a/scripts/adjust_autoksyms.sh
+++ b/scripts/adjust_autoksyms.sh
@@ -48,9 +48,6 @@ case "${KCONFIG_CONFIG}" in
. "./${KCONFIG_CONFIG}"
esac
-# In case it doesn't exist yet...
-if [ -e "$cur_ksyms_file" ]; then touch "$cur_ksyms_file"; fi
-
# Generate a new ksym list file with symbols needed by the current
# set of modules.
cat > "$new_ksyms_file" << EOT
--
2.7.4
Just a trivial change to prepare for the next commit.
This target is still invisible from external module building.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Changes in v2: None
Makefile | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/Makefile b/Makefile
index ac8755d..f8e9e12 100644
--- a/Makefile
+++ b/Makefile
@@ -567,14 +567,6 @@ endif
export KBUILD_MODULES KBUILD_BUILTIN
ifeq ($(KBUILD_EXTMOD),)
-# Additional helpers built in scripts/
-# Carefully list dependencies so we do not try to build scripts twice
-# in parallel
-PHONY += scripts
-scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
- asm-generic gcc-plugins
- $(Q)$(MAKE) $(build)=$(@)
-
# Objects we will link into vmlinux / subdirs we need to visit
init-y := init/
drivers-y := drivers/ sound/ firmware/
@@ -1070,6 +1062,13 @@ endef
include/config/kernel.release: include/config/auto.conf FORCE
$(call filechk,kernel.release)
+# Additional helpers built in scripts/
+# Carefully list dependencies so we do not try to build scripts twice
+# in parallel
+PHONY += scripts
+scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
+ asm-generic gcc-plugins autoksyms
+ $(Q)$(MAKE) $(build)=$(@)
# Things we need to do before we recursively start building the kernel
# or the modules are listed in "prepare".
--
2.7.4
On Fri, 16 Mar 2018, Masahiro Yamada wrote:
> The comment mentions it creates autoksyms.h in case it is missing,
> but the actual code touches it when it does exists.
>
> The build system creates it anyway because <linux/export.h> and
> <asm-generic/export.h> need it.
>
> The code would not have worked as intended, and people have not
> noticed it. This is a proof that we can simply remove it.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
> ---
>
> Changes in v2:
> - Remove the code instead of fixing it
>
> scripts/adjust_autoksyms.sh | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh
> index a162258..e0dd0d5 100755
> --- a/scripts/adjust_autoksyms.sh
> +++ b/scripts/adjust_autoksyms.sh
> @@ -48,9 +48,6 @@ case "${KCONFIG_CONFIG}" in
> . "./${KCONFIG_CONFIG}"
> esac
>
> -# In case it doesn't exist yet...
> -if [ -e "$cur_ksyms_file" ]; then touch "$cur_ksyms_file"; fi
> -
> # Generate a new ksym list file with symbols needed by the current
> # set of modules.
> cat > "$new_ksyms_file" << EOT
> --
> 2.7.4
>
>
On Fri, 16 Mar 2018, Masahiro Yamada wrote:
> The idea of using fixdep was inspired by Kconfig, but autoksyms
> belongs to a different group. So, I want move those touched files
> under include/config/ksym/ to include/ksym/.
>
> The directory include/ksym/ can be removed by "make clean" because
> it is meaningless for the external module building.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
> ---
>
> Changes in v2:
> - Rebase on linux-next
> (resolve a conflict to https://patchwork.kernel.org/patch/10204653/)
>
> .gitignore | 1 +
> Makefile | 2 +-
> scripts/Kbuild.include | 2 +-
> scripts/adjust_autoksyms.sh | 2 +-
> scripts/basic/fixdep.c | 8 ++++----
> 5 files changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/.gitignore b/.gitignore
> index 1be78fd..85bcc26 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -87,6 +87,7 @@ modules.builtin
> #
> include/config
> include/generated
> +include/ksym
> arch/*/include/generated
>
> # stgit generated dirs
> diff --git a/Makefile b/Makefile
> index ef42adb..5fee703 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1338,7 +1338,7 @@ endif # CONFIG_MODULES
> # make distclean Remove editor backup files, patch leftover files and the like
>
> # Directories & files removed with 'make clean'
> -CLEAN_DIRS += $(MODVERDIR)
> +CLEAN_DIRS += $(MODVERDIR) include/ksym
>
> # Directories & files removed with 'make mrproper'
> MRPROPER_DIRS += include/config usr/include include/generated \
> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> index f9c2f07..cce31ee 100644
> --- a/scripts/Kbuild.include
> +++ b/scripts/Kbuild.include
> @@ -366,7 +366,7 @@ ksym_dep_filter = \
> $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \
> boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;; \
> *) echo "Don't know how to preprocess $(1)" >&2; false ;; \
> - esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/KSYM_\1/p'
> + esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/_\1/p'
>
> cmd_and_fixdep = \
> $(echo-cmd) $(cmd_$(1)); \
> diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh
> index e0dd0d5..f11cae6 100755
> --- a/scripts/adjust_autoksyms.sh
> +++ b/scripts/adjust_autoksyms.sh
> @@ -80,7 +80,7 @@ sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u |
> sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | tr "A-Z_" "a-z/" |
> while read sympath; do
> if [ -z "$sympath" ]; then continue; fi
> - depfile="include/config/ksym/${sympath}.h"
> + depfile="include/ksym/${sympath}.h"
> mkdir -p "$(dirname "$depfile")"
> touch "$depfile"
> echo $((count += 1))
> diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c
> index 449b68c..f387538 100644
> --- a/scripts/basic/fixdep.c
> +++ b/scripts/basic/fixdep.c
> @@ -113,11 +113,11 @@ static void usage(void)
> /*
> * Print out a dependency path from a symbol name
> */
> -static void print_config(const char *m, int slen)
> +static void print_dep(const char *m, int slen, const char *dir)
> {
> int c, i;
>
> - printf(" $(wildcard include/config/");
> + printf(" $(wildcard %s/", dir);
> for (i = 0; i < slen; i++) {
> c = m[i];
> if (c == '_')
> @@ -140,7 +140,7 @@ static void do_extra_deps(void)
> fprintf(stderr, "fixdep: bad data on stdin\n");
> exit(1);
> }
> - print_config(buf, len - 1);
> + print_dep(buf, len - 1, "include/ksym");
> }
> }
>
> @@ -208,7 +208,7 @@ static void use_config(const char *m, int slen)
> return;
>
> define_config(m, slen, hash);
> - print_config(m, slen);
> + print_dep(m, slen, "include/config");
> }
>
> /* test if s ends in sub */
> --
> 2.7.4
>
>
On Fri, 16 Mar 2018, Masahiro Yamada wrote:
> Currently LDFLAGS is not cleared, so same flags are accumulated in
> LDFLAGS when the top Makefile is recursively invoked.
>
> I found unneeded rebuild for ARCH=arm64 when CONFIG_TRIM_UNUSED_KSYMS
> is enabled. If include/generated/autoksyms.h is updated, the top
> Makefile is recursively invoked, then arch/arm64/Makefile adds one
> more '-maarch64linux'. Due to the command line change, modules are
> rebuilt needlessly.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
> ---
>
> Changes in v2: None
>
> Makefile | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/Makefile b/Makefile
> index d9bb6dd6..ac8755d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -437,6 +437,7 @@ KBUILD_CFLAGS_KERNEL :=
> KBUILD_AFLAGS_MODULE := -DMODULE
> KBUILD_CFLAGS_MODULE := -DMODULE
> KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
> +LDFLAGS :=
> GCC_PLUGINS_CFLAGS :=
>
> export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
> --
> 2.7.4
>
>
The external module building does not need to parse this code because
KBUILD_MODULES is always set anyway.
Move this code inside the "ifeq ($(KBUILD_EXTMOD),) ... endif" block.
Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
---
Changes in v2: None
Makefile | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/Makefile b/Makefile
index 0a3895c..ef42adb 100644
--- a/Makefile
+++ b/Makefile
@@ -614,13 +614,6 @@ else
include/config/auto.conf: ;
endif # $(dot-config)
-# For the kernel to actually contain only the needed exported symbols,
-# we have to build modules as well to determine what those symbols are.
-# (this can be evaluated only once include/config/auto.conf has been included)
-ifdef CONFIG_TRIM_UNUSED_KSYMS
- KBUILD_MODULES := 1
-endif
-
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
@@ -1021,6 +1014,13 @@ ifdef CONFIG_TRIM_UNUSED_KSYMS
"$(MAKE) -f $(srctree)/Makefile vmlinux"
endif
+# For the kernel to actually contain only the needed exported symbols,
+# we have to build modules as well to determine what those symbols are.
+# (this can be evaluated only once include/config/auto.conf has been included)
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+ KBUILD_MODULES := 1
+endif
+
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
$(autoksyms_h):
--
2.7.4
On Fri, 16 Mar 2018, Masahiro Yamada wrote:
> +# Recurse until adjust_autoksyms.sh is satisfied
> +PHONY += autoksyms_recursive
> +autoksyms_recursive: $(vmlinux-deps)
> + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
> "$(MAKE) -f $(srctree)/Makefile vmlinux"
> -endif
>
> # For the kernel to actually contain only the needed exported symbols,
> # we have to build modules as well to determine what those symbols are.
> @@ -1034,7 +1024,13 @@ cmd_link-vmlinux = \
> $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>
> -vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
> +vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
Don't you have to make the autoksyms_recursive dependency conditional on
CONFIG_TRIM_UNUSED_KSYMS?
Nicolas
2018-03-16 11:32 GMT+09:00 Nicolas Pitre <[email protected]>:
> On Fri, 16 Mar 2018, Masahiro Yamada wrote:
>
>> +# Recurse until adjust_autoksyms.sh is satisfied
>> +PHONY += autoksyms_recursive
>> +autoksyms_recursive: $(vmlinux-deps)
>> + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
>> "$(MAKE) -f $(srctree)/Makefile vmlinux"
>> -endif
>>
>> # For the kernel to actually contain only the needed exported symbols,
>> # we have to build modules as well to determine what those symbols are.
>> @@ -1034,7 +1024,13 @@ cmd_link-vmlinux = \
>> $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
>> $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
>>
>> -vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
>> +vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
>
> Don't you have to make the autoksyms_recursive dependency conditional on
> CONFIG_TRIM_UNUSED_KSYMS?
>
Oops, I accidentally removed that conditional.
I will fix it shortly. Thanks!
--
Best Regards
Masahiro Yamada