[dpdk-dev] [PATCH v3 01/17] mk: Introduce ARMv7 architecture

[David Marchand]

Hello Jan,

On Tue, Oct 27, 2015 at 8:13 PM, Jan Viktorin <viktorin at rehivetech.com>
wrote:

>
> diff --git a/config/defconfig_arm-armv7-a-linuxapp-gcc
> b/config/defconfig_arm-armv7-a-linuxapp-gcc
> new file mode 100644
> index 0000000..5a778cf
> --- /dev/null
> +++ b/config/defconfig_arm-armv7-a-linuxapp-gcc
> +
> +# avoids using i686/x86_64 SIMD instructions, nothing for ARM
> +CONFIG_RTE_BITMAP_OPTIMIZATIONS=0
>

(<unrelated>yet another build flag which has to disappear, and bitmap
header should be moved from librte_sched to eal with arch-specific
implementations when applicable</unrelated>)

Well, I am a bit confused by this comment.
For me, gcc provides ctzll builtins.
https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html

And with your patchset applied, it builds fine with
RTE_BITMAP_OPTIMIZATIONS enabled using gcc 4.7.3 for arm on ubuntu 14.04.
Is there a dependency on gcc version ?


+# PCI is usually not used on ARM
> +CONFIG_RTE_EAL_IGB_UIO=n
>

Not sure "usually not used" is a good reason to disable something.
Is there a real issue on arm with igb_uio code (compilation, pci accesses) ?


Thanks.

-- 
David Marchand