Re: [dpdk-stable] [PATCH v2] build: enable Arm NEON flags when __aarch64__ is defined

[Yongseok Koh <yskoh@mellanox.com>]

> On Sep 3, 2018, at 1:25 AM, Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com> wrote:
> 
> 
> 
> -----Original Message-----
> From: Yongseok Koh <yskoh@mellanox.com> 
> Sent: Sunday, September 2, 2018 7:00 PM
> To: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
> Cc: stable@dpdk.org; nd <nd@arm.com>
> Subject: Re: [dpdk-stable] [PATCH v2] build: enable Arm NEON flags when __aarch64__ is defined
> 
>> On Sep 2, 2018, at 12:59 PM, Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com> wrote:
>> 
>> -----Original Message-----
>> From: Yongseok Koh <yskoh@mellanox.com>
>> Sent: Sunday, September 2, 2018 2:30 PM
>> To: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
>> Cc: stable@dpdk.org
>> Subject: Re: [dpdk-stable] [PATCH v2] build: enable Arm NEON flags 
>> when __aarch64__ is defined
>> 
>>> On Sep 2, 2018, at 11:32 AM, Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com> wrote:
>>> 
>>> GCC version 4.8.5 does not pre-define __ARM_NEON. NEON is not 
>>> optional for ArmV8. Hence NEON related code can be enabled when 
>>> __aarch64__ is defined.
>>> 
>>> Bugzilla ID: 82
>>> Cc: stable@dpdk.org
>>> 
>>> Reported-by: Raslan Darawsheh <rasland@mellanox.com>
>>> Reported-by: Thomas F Herbert <therbert@redhat.com>
>>> Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
>>> Reviewed-by: Phil Yang <phil.yang@arm.com>
>>> Reviewed-by: Gavin Hu <gavin.hu@arm.com>
>>> Acked-by: Gavin Hu <gavin.hu@arm.com>
>>> Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
>>> ---
>>> V2:
>>> * Corrected the order of contribution tags
>>> * Added Jerin's Ack
>> 
>> I didn't check out the details yet but a quick question.
>> Do you want me to include this patch in 17.11.4?
>> 
>> Yes, please include.
> 
> I didn't realized that this is fixing the meson build.
> 17.11 doesn't have that.
> 
> Thanks,
> Yongseok
> 
> It has a fix for the make build as well. Does it mean, it needs to be a different patch?

I could've applied the second hunk but actually it was one minute before the
release of 17.11.4. I'm sorry that I had to skip this patch for the release.

But, I've applied it (the second hunk only) to the stable/17.11 tree today.
Please check it out and let me know if there's an issue.  This will be included
in 17.11.5 (ETA is Nov).

FYI, the most favorable way is that you send patches with '[PATCH 17.11]' prefix
based on the latest stable/17.11 so that it is never forgotten.


Thanks,
Yongseok

>>> config/arm/meson.build | 3 ++-
>>> mk/rte.cpuflags.mk     | 2 +-
>>> 2 files changed, 3 insertions(+), 2 deletions(-)
>>> 
>>> diff --git a/config/arm/meson.build b/config/arm/meson.build index
>>> 40dbc87..94cca49 100644
>>> --- a/config/arm/meson.build
>>> +++ b/config/arm/meson.build
>>> @@ -157,7 +157,8 @@ else
>>> endif
>>> message(machine_args)
>>> 
>>> -if cc.get_define('__ARM_NEON', args: machine_args) != ''
>>> +if (cc.get_define('__ARM_NEON', args: machine_args) != '' or
>>> +    cc.get_define('__aarch64__', args: machine_args) != '')
>>> 	dpdk_conf.set('RTE_MACHINE_CPUFLAG_NEON', 1)
>>> 	compile_time_cpuflags += ['RTE_CPUFLAG_NEON'] endif diff --git 
>>> a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk index 6071313..43ed841
>>> 100644
>>> --- a/mk/rte.cpuflags.mk
>>> +++ b/mk/rte.cpuflags.mk
>>> @@ -89,7 +89,7 @@ CPUFLAGS += VSX
>>> endif
>>> 
>>> # ARM flags
>>> -ifneq ($(filter $(AUTO_CPUFLAGS),__ARM_NEON),)
>>> +ifneq ($(filter __ARM_NEON __aarch64__,$(AUTO_CPUFLAGS)),)
>>> CPUFLAGS += NEON
>>> endif
>>> 
>>> --
>>> 2.7.4