On Fri, Feb 7, 2020 at 7:08 PM Quentin Perret <qperret@xxxxxxxxxx> wrote: > > When doing a cold build, autoksyms.h starts empty, and is updated late > in the build process to have visibility over the symbols used by in-tree > drivers. But since the symbol whitelist is known upfront, it can be used > to pre-populate autoksyms.h and maximize the amount of code that can be > compiled to its final state in a single pass, hence reducing build time. > > Do this by using gen_autoksyms.sh to initialize autoksyms.h instead of > creating an empty file. > > Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx> > --- > Makefile | 2 +- > scripts/gen_autoksyms.sh | 3 ++- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/Makefile b/Makefile > index 6a01b073915e..e5c389d189f7 100644 > --- a/Makefile > +++ b/Makefile > @@ -1065,7 +1065,7 @@ autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h) > > $(autoksyms_h): > $(Q)mkdir -p $(dir $@) > - $(Q)touch $@ > + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@ Now that this line is doing a non-trivial task, it might be a good idea to show a short log, like this: GEN include/generated/autoksyms.h You can do it like this: quiet_cmd_autoksyms_h = GEN $@ cmd_autoksyms_h = mkdir -p $(dir $@); $(BASH) $(srctree)/scripts/gen_autoksyms.sh $@ $(autoksyms_h): $(call cmd,autoksyms_h) > > ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) > > diff --git a/scripts/gen_autoksyms.sh b/scripts/gen_autoksyms.sh > index ce0919c3791a..ae033ab03a4a 100755 > --- a/scripts/gen_autoksyms.sh > +++ b/scripts/gen_autoksyms.sh > @@ -32,7 +32,8 @@ cat > "$output_file" << EOT > > EOT > > -sed 's/ko$/mod/' modules.order | > +[[ -f modules.order ]] && modlist=modules.order || modlist=/dev/null > +sed 's/ko$/mod/' $modlist | > xargs -n1 sed -n -e '2{s/ /\n/g;/^$/!p;}' -- | > cat - "$ksym_wl" | > sort -u | > -- > 2.25.0.341.g760bfbb309-goog > -- Best Regards Masahiro Yamada