[PATCH 0/19] removal of mach/vmalloc.h and generic optimizations

[Nicolas Pitre]

On Sat, 17 Sep 2011, Arnd Bergmann wrote:

> On Friday 16 September 2011 03:07:11 Nicolas Pitre wrote:
> > This patch series removes all instances of mach/vmalloc.h in order to
> > have a more unified memory map across all ARM architectures.  To do so,
> > the static mappings are moved inside the vmalloc area.  And finally this
> > allows for a generic optimization to ioremap where static mappings are
> > reused whenever possible, using common code instead of having this
> > duplicated in a couple places.
> > 
> > This also provides a net reduction of more than 1200 lines of code.
> > 
> > Those patches are also available in the following repository:
> > 
> >         git://git.linaro.org/people/nico/linux vmalloc
> 
> Hi Nicolas,
> 
> I like the series a lot. I had planned to work on this myself, but
> I guess you did a better job than I could have anyway.

Thanks!

> Doing some randconfig tests, I noticed that your series is currently broken
> on shmobile, which triggers a 
> 
> 	BUILD_BUG_ON(VMALLOC_END > CONSISTENT_BASE);
> 
> in mem_init(), because the platform has a CONSISTENT_DMA_SIZE of 158MB.
> All other platforms have a CONSISTENT_DMA_SIZE of at most 14MB, which
> works correctly.

Any idea why shmobile requires such an amount of consistent memory?

> My feeling is that a 158MB CONSISTENT_DMA_SIZE causes other problems
> anyway because we cannot map regular RAM both cached and uncached,
> but this is still a regression. The problem might be solved using
> Marek's CMA patches, which should eliminate the need for a huge
> CONSISTENT_DMA_SIZE.

Maybe.  However I don't want for this series to depend on CMA.  I'll 
find some temporary hack in the mean time.


Nicolas