Re: [PATCH 0/5] compat / compat-wireless: merge autoconf generation

["Luis R. Rodriguez" <rodrigue@qca.qualcomm.com>]

On Sat, Feb 25, 2012 at 12:05:46PM +0100, Hauke Mehrtens wrote:
> On 02/25/2012 02:52 AM, Luis R. Rodriguez wrote:
> > From: Luis R. Rodriguez <mcgrof@frijolero.org>
> > 
> > While testing ckmake cross compiling compat through different kernels I
> > realized that compat was failing to build on some kernels but compat-wireless
> > was not. The reason for this turned out to be that compat did not have an
> > autoconf for the CONFIG_COMPAT_KERNEL_* variables. In order to make use
> > of a variable properly in code on kernel we need two things: a makefile
> > equivalent and a header file that defines it. The compat project had
> > only makefile variable generation while compat-wireless had makefile
> > variable generation with a *few* variables propagated to actual code.
> > 
> > To avoid issues with this any further I've decided to try merging the
> > autoconf effort for both projects and taking leads on what compat does
> > first.
> > 
> > compat then does the CONFIG_COMPAT_KERNEL_* trickery and generates a
> > clean .config for us. This in turn generates our compat's compat_autoconf.h.
> > The compat-wireless project leverages this work by dropping its own
> > Makefile hackery in favor of the same work and later also uses the same
> > .config to expand its own compat_autoconf.h.
> > 
> > John, I could use some extra help on reviewing the RHEL stuff. I'm going
> > to push this stuff out now to help with testing.
> > 
> > compat:
> > 
> > Luis R. Rodriguez (2):
> >   compat: fix few compilations by adding compat_autoconf.h support
> >   compat: add some initial RHEL support
> > 
> >  .gitignore                      |   10 ++++
> >  Makefile                        |   59 ++++++++++------------
> >  include/linux/compat_autoconf.h |   37 --------------
> >  scripts/gen-compat-autoconf.sh  |  105 +++++++++++++++++++++++++++++++++++++++
> >  scripts/gen-compat-config.sh    |   60 ++++++++++++++++++++++
> >  5 files changed, 201 insertions(+), 70 deletions(-)
> >  delete mode 100644 include/linux/compat_autoconf.h
> >  create mode 100755 scripts/gen-compat-autoconf.sh
> >  create mode 100755 scripts/gen-compat-config.sh
> > 
> > compat-wireless:
> > 
> > Luis R. Rodriguez (3):
> >   compat-wireless: fix old checks on KERNEL_SUBLEVEL
> >   compat-wireless: start using CONFIG_COMPAT_KERNEL_ in code
> >   compat-wireless: use compat's CONFIG_COMPAT_KERNEL_* variables
> >  Makefile                       |   22 ++++++++++++++++------
> >  config.mk                      |   24 ++++--------------------
> >  scripts/check_config.sh        |    9 +++++----
> >  scripts/gen-compat-autoconf.sh |   13 +++++++------
> >  4 files changed, 32 insertions(+), 36 deletions(-)
> > 
> 
> This patch series breaks parallel build.
> Before these patches where applied parallel build was no problem I just
> saw two error at the beginning, but after this patch series it does not
> work any more.
> 
> These are the current error messages at the beginning and then it
> compiles sequential.
> 
> Hauke
> 
> hauke@hauke:~/compat-wireless/compat-wireless$ make -j5
> make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent
> make rule.
> make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent
> make rule.
> ./scripts/gen-compat-autoconf.sh .config config.mk >
> include/linux/compat_autoconf.h
> make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent
> make rule.
> make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent
> make rule.
> make -C /home/hauke/compat-wireless/compat-wireless modules
> make[1]: Entering directory `/home/hauke/compat-wireless/compat-wireless'
> make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent
> make rule.
> make -C /lib/modules/3.0.0-16-generic/build
> M=/home/hauke/compat-wireless/compat-wireless modules
> make[2]: Entering directory `/usr/src/linux-headers-3.0.0-16-generic'
>   LD      /home/hauke/compat-wireless/compat-wireless/compat/built-in.o

I had at first the below cheasy fix, but now I have an even better one
that does not require recursion. I'll post and merge. Thanks for reporting
this.

diff --git a/Makefile b/Makefile
index d96d098..d11da17 100644
--- a/Makefile
+++ b/Makefile
@@ -62,8 +62,8 @@ install: modules
 $(COMPAT_AUTOCONF): ;
 
 $(COMPAT_CONFIG):
-	@$(PWD)/scripts/gen-compat-config.sh > $(PWD)/$(COMPAT_CONFIG)
-	@$(PWD)/scripts/gen-compat-autoconf.sh $(COMPAT_CONFIG) > $(PWD)/$(COMPAT_AUTOCONF)
+	+@$(PWD)/scripts/gen-compat-config.sh > $(PWD)/$(COMPAT_CONFIG)
+	+@$(PWD)/scripts/gen-compat-autoconf.sh $(COMPAT_CONFIG) > $(PWD)/$(COMPAT_AUTOCONF)
 	@$(MAKE) -C $(PWD) modules
 
 kkinstall: modules