Re: [dpdk-dev] [PATCH v5 0/2] Balanced allocation of hugepages

[Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>]

On 20/06/2017 16:41, Jerin Jacob wrote:
> -----Original Message-----
>> Date: Tue, 20 Jun 2017 15:58:50 +0100
>> From: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
>> To: Thomas Monjalon <thomas@monjalon.net>, Ilya Maximets
>>   <i.maximets@samsung.com>
>> CC: dev@dpdk.org, Hemant Agrawal <hemant.agrawal@nxp.com>, Bruce Richardson
>>   <bruce.richardson@intel.com>, David Marchand <david.marchand@6wind.com>,
>>   Heetae Ahn <heetae82.ahn@samsung.com>, Yuanhan Liu <yliu@fridaylinux.org>,
>>   Jianfeng Tan <jianfeng.tan@intel.com>, Neil Horman
>>   <nhorman@tuxdriver.com>, Yulong Pei <yulong.pei@intel.com>
>> Subject: Re: [dpdk-dev] [PATCH v5 0/2] Balanced allocation of hugepages
>> User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101
>>   Thunderbird/45.1.1
>>
>> On 20/06/2017 15:35, Thomas Monjalon wrote:
>>> 20/06/2017 15:58, Ilya Maximets:
>>>> On 20.06.2017 16:07, Thomas Monjalon wrote:
>>>>> 19/06/2017 13:10, Hemant Agrawal:
>>>>>>>>> On Thu, Jun 08, 2017 at 02:21:58PM +0300, Ilya Maximets wrote:
>>>>>>>>>> So, there are 2 option:
>>>>>>>>>>
>>>>>>>>>>       1. Return back config option RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES
>>>>>>>>>>          from the first version of the patch and disable it by default.
>>>>>>>>>>
>>>>>>>>>>       2. Keep patch as it is now and make everyone install libnuma
>>>>>>>>>>          for successful build.
>>>>>> +1 for option 1
>>>>>> It will be a issue and undesired dependency for SoCs, not supporting
>>>>>> NUMA architecture.
>>>>>>
>>>>>> It can be added to the config, who desired to use it by default.
>>>>> Yes I agree, it cannot be a dependency for architectures which
>>>>> do not support NUMA.
>>>>> Please can we rework the patch so that only one node is assumed
>>>>> if NUMA is disabled for the architecture?
>> Ilya, I missed that libnuma is not supported on ARM.
> It is supported on arm64 and arm64 has NUMA machines(thunderx, thunderx2) too.
>
> [dpdk.org] $ dpkg-query -L libnuma-dev
> /.
> /usr
> /usr/lib
> /usr/lib/aarch64-linux-gnu
> /usr/lib/aarch64-linux-gnu/libnuma.a
> /usr/share
> /usr/share/man
> /usr/share/man/man3
> /usr/share/man/man3/numa.3.gz
> /usr/share/doc
> /usr/share/doc/libnuma-dev
> /usr/share/doc/libnuma-dev/copyright
> /usr/include
> /usr/include/numaif.h
> /usr/include/numa.h
> /usr/include/numacompat1.h
> /usr/lib/aarch64-linux-gnu/libnuma.so
>

Is it ARMv7 then the only supported arch missing libnuma support?

>>>> We're still don't have dynamic build time configuration system.
>>>> To make get/set_mempolicy work we need to include <numaif.h>
>>>> and have libnuma for successful linkage.
>>>> This means that the only option to not have libnuma as dependency
>>>> is to return back configuration option RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES
>>>> as it was in the first version of the patch.
>>>>
>>>> There is, actually, the third option (besides 2 already described):
>>>>
>>>> 	3. Return back config option RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES
>>>> 	   from the first version of the patch and *enable* it by default.
>>>> 	   In this case anyone who doesn't want to have libnuma as dependency
>>>> 	   will be able to disable the config option manually.
>>>>
>>>> Thomas, what do you think? Bruce? Sergio?
>>> It should be enabled on x86 and ppc, and disabled in other
>>> default configurations (ARM for now).
>> Agree.
>>
>>>> P.S. We're always able to implement syscall wrappers by hands without any
>>>>        external dependencies, but I don't think it's a good decision.
>>> I agree to use libnuma instead of re-inventing the wheel.
>>> Let's just make it optional at build time and fallback on one node
>>> if disabled.
>> That is the simple way out.
>>
>> Sergio