| Message ID | 1510818396-17443-1-git-send-email-yamada.masahiro@socionext.com |
|---|---|
| State | New |
| Headers | show |
| Series | kbuild: define KBUILD_MODNAME even if multiple modules share objects | expand |
On 11/16/2017 03:46 PM, Masahiro Yamada wrote: > Currently, KBUILD_MODNAME is defined only when $(modname) contains > just one word. If an object is shared between multiple modules, > undefined KBUILD_MODNAME causes a build error. > > A simple test case is as follows: > > obj-m += foo.o > obj-m += bar.o > foo-objs := foo-bar-common.o foo-main.o > bar-objs := foo-bar-common.o bar-main.o > > In this case, we do not know what to define for KBUILD_MODNAME when > compiling foo-bar-common.o ("foo" or "bar" ?), so one reasonable > solution is let it fall back to $(basetarget) (= "foo-bar-common"). > > It would be better to avoid such a design where possible, but we > already have such a case, for example, > drivers/net/ethernet/cavium/liquidio/Makefile > > I slightly refactored implementation; we can check $(word 2, $(modname)) > instead of $(filter 1,$(words $(modname))). > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > scripts/Makefile.lib | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index 5fbc46d..9f9a7df 100644 > --- a/scripts/Makefile.lib > +++ b/scripts/Makefile.lib > @@ -86,8 +86,7 @@ subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) > # differ in different configs. > name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) > basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) > -modname_flags = $(if $(filter 1,$(words $(modname))),\ > - -DKBUILD_MODNAME=$(call name-fix,$(modname))) > +modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(if $(word 2,$(modname)),$(basetarget),$(modname))) > > orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ > $(ccflags-y) $(CFLAGS_$(basetarget).o) > I like this style of the refactor, because it is a bit more readable according to human mind, and it also behave the same as before in the case drivers/net/ethernet/cavium/liquidio/Makefile: modname = $(basetarget). So: Tested-by: Cao jin <caoj.fnst@cn.fujitsu.com> Reviewed-by: Cao jin <caoj.fnst@cn.fujitsu.com> -- Sincerely, Cao jin
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 5fbc46d..9f9a7df 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -86,8 +86,7 @@ subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) # differ in different configs. name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) -modname_flags = $(if $(filter 1,$(words $(modname))),\ - -DKBUILD_MODNAME=$(call name-fix,$(modname))) +modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(if $(word 2,$(modname)),$(basetarget),$(modname))) orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ $(ccflags-y) $(CFLAGS_$(basetarget).o)
Currently, KBUILD_MODNAME is defined only when $(modname) contains just one word. If an object is shared between multiple modules, undefined KBUILD_MODNAME causes a build error. A simple test case is as follows: obj-m += foo.o obj-m += bar.o foo-objs := foo-bar-common.o foo-main.o bar-objs := foo-bar-common.o bar-main.o In this case, we do not know what to define for KBUILD_MODNAME when compiling foo-bar-common.o ("foo" or "bar" ?), so one reasonable solution is let it fall back to $(basetarget) (= "foo-bar-common"). It would be better to avoid such a design where possible, but we already have such a case, for example, drivers/net/ethernet/cavium/liquidio/Makefile I slightly refactored implementation; we can check $(word 2, $(modname)) instead of $(filter 1,$(words $(modname))). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- scripts/Makefile.lib | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.7.4