From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Viktorin <viktorin@rehivetech.com>
Subject: Re: [PATCH v3 4/4] eal/arm: introduce
 CONFIG_RTE_ARCH_ARM_NEON_MEMCPY
Date: Sun, 20 Mar 2016 10:46:55 +0100
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To: Thomas Monjalon <thomas.monjalon@6wind.com>
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On Sun, 20 Mar 2016 10:41:10 +0100
Jan Viktorin <viktorin@rehivetech.com> wrote:

> On Sat, 19 Mar 2016 21:14:57 +0100
> Thomas Monjalon <thomas.monjalon@6wind.com> wrote:
> 
> > 2016-03-19 20:58, Jan Viktorin:  
> > > The flag is used to enable memcpy optimizations in EAL. As it is not always
> > > the performance benefit, the flag allows to disable it.    
> > 
> > Ideally the default should be to choose the best optimization.
> > If it is not possible, it would help to have some comments explaining
> > how to choose wether enabling NEON memcpy or not.

The related statistics are mentioned here:

commit 04a2fde35daf5e9a271e72331a70b48b951d7568
Author: Vlastimil Kosar <kosar@rehivetech.com>
Date:   Tue Nov 3 00:47:20 2015 +0100

    eal/arm: add vector memcpy for ARMv7

It's quite difficult to easily summarize it, especially for so many
CPUs...
 
> 
> Ok, we can rename the option to CONFIG_RTE_ARCH_ARM_AVOID_NEON_MEMCPY,
> delete it from the defconfig and change the test in rte_memcpy_32.h to
> 
> #ifndef CONFIG_RTE_ARCH_ARM_AVOID_NEON_MEMCPY
> 
> Alternatively, to have a positive test like
> 
> #ifdef CONFIG_RTE_ARCH_ARM_AVOID_NEON_MEMCPY
> 
> I can create a bigger change that moves the non-neon-memcpy up in the
> file...
> 
> Should I resend the whole series as v3?
> 
> Regards
> Jan


-- 
  Jan Viktorin                E-mail: Viktorin@RehiveTech.com
  System Architect            Web:    www.RehiveTech.com
  RehiveTech
  Brno, Czech Republic