[Mesa-dev] [PATCH 09/15] i965: Build the driver into a shared mesa_dri_drivers.so .

[Chad Versace]

On 10/11/2013 06:03 PM, Eric Anholt wrote:
> Previously, we've split things such that mesa core is in libdricore,
> exposing the whole Mesa core interface in the global namespace, and the
> i965_dri.so code all links against that.  Along with polluting application
> namespace terribly, it requires extra PLT indirections and prevents LTO.
>
> Instead, we can build all of the driver contents into the same .so with
> just a few symbols exposed to be referenced from the actual driver .so
> file, allowing LTO and reducing our exposed symbol count massively.
>
> FPS improvement on GLB2.7 with INTEL_NO_HW=1: 2.61061% +/- 1.16957% (n=50)
> (without LTO, just the PLT reductions from this commit)
>
> v2: Set a global driverAPI variable so loaders don't have to update to
>      createNewScreen2() (though they may want to for thread safety).
>
> Reviewed-by: Matt Turner <mattst88 at gmail.com> (v1)
> ---
>   configure.ac                                  | 29 +++++++++++---
>   src/mesa/drivers/dri/Makefile.am              | 54 ++++++++++++++++++++++++++-
>   src/mesa/drivers/dri/common/Makefile.am       |  3 ++
>   src/mesa/drivers/dri/common/dri_util.c        | 19 +++++++++-
>   src/mesa/drivers/dri/common/dri_util.h        |  2 +-
>   src/mesa/drivers/dri/common/megadriver_stub.c | 41 ++++++++++++++++++++
>   src/mesa/drivers/dri/i965/Makefile.am         | 27 +++-----------
>   src/mesa/drivers/dri/i965/intel_screen.c      | 18 +++++++--
>   src/mesa/drivers/dri/i965/intel_screen.h      |  2 +
>   9 files changed, 162 insertions(+), 33 deletions(-)
>   create mode 100644 src/mesa/drivers/dri/common/megadriver_stub.c
>



> +# Add a link to allow setting LD_LIBRARY_PATH/LIBGL_DRIVERS_PATH to /lib of the build tree.
> +all-local: mesa_dri_drivers.la
> +	$(MKDIR_P) $(top_builddir)/$(LIB_DIR);
> +	$(AM_V_GEN)ln -f .libs/mesa_dri_drivers.so \
> +			 $(top_builddir)/$(LIB_DIR)/mesa_dri_drivers.so;
> +	$(AM_V_GEN)for i in $(MEGADRIVERS); do \
> +		ln -f $(top_builddir)/$(LIB_DIR)/mesa_dri_drivers.so \
> +		      $(top_builddir)/$(LIB_DIR)/$$i; \
> +	done;
> +
> +# hardlink each megadriver instance, but don't actually have
> +# mesa_dri_drivers.so in the set of final installed files.
> +install-data-hook:
> +	for i in $(MEGADRIVERS); do \
> +		ln -f $(dridir)/mesa_dri_drivers.so \
> +		      $(dridir)/$$i; \
> +	done;
> +	$(RM) -f $(dridir)/mesa_dri_drivers.so
> +	$(RM) -f $(dridir)/mesa_dri_drivers.la
> +
> +endif


This hunk breaks `make install` for me. I'm doing an out-of-tree build and
installing to --prefix=/usr. Here's the error:

make[7]: Entering directory `/home/chad/exp/makepkg/abs/mesa/src/src/mesa/drivers/dri'
for i in  i965_dri.so    ; do \
         ln -f /usr/lib/xorg/modules/dri/mesa_dri_drivers.so \
               /usr/lib/xorg/modules/dri/$i; \
done;
ln: failed to access '/usr/lib/xorg/modules/dri/mesa_dri_drivers.so': No such file or directory

It seems that the Makefile never install mesa_dri_drivers.so to $(dridir), but
then tries to ln it. I don't speak autotools, so I don't see how to fix this.