[dpdk-dev] [PATCH v2] examples/l3fwd: fix aliasing in port grouping

[Ferruh Yigit]

On 11/6/2017 12:18 AM, Jianbo Liu wrote:
> The 11/06/2017 09:59, Jerin Jacob wrote:
>> -----Original Message-----
>>> Date: Fri,  3 Nov 2017 16:13:51 +0530
>>> From: Guduri Prathyusha <gprathyusha at caviumnetworks.com>
>>> To: tomasz.kantecki at intel.com
>>> CC: Jianbo.Liu at arm.com, guduriprathyusha at gmail.com,
>>>  konstantin.ananyev at intel.com, dev at dpdk.org, Guduri Prathyusha
>>>  <gprathyusha at caviumnetworks.com>
>>> Subject: [dpdk-dev] [PATCH v2] examples/l3fwd: fix aliasing in port grouping
>>> X-Mailer: git-send-email 2.14.1
>>>
>>> With -f-strict-aliasing enabled by default from -O2, gcc > 5.x gives
>>> undefined behavior in port_groupx4 in ARM. 'pn' and 'pnum' are
>>> two different pointers pointing to same chunk of memory and
>>> with -f-strict-aliasing the pointers are assumed to be pointing to
>>> different memory and compiler reorders instructions that depend on
>>> pnum and pn. This breaks port grouping algorithm.
>>>
>>> This patch eliminates the above problem by introducing a compiler
>>> barrier between the instructions that depend on pnum, pn and lp.
>>>
>>> Fixes: 569b290cdb36 ("examples/l3fwd: add NEON implementation")
>>>
>>> Signed-off-by: Guduri Prathyusha <gprathyusha at caviumnetworks.com>
>>
>> Acked-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>
> 
> Acked-by: Jianbo Liu <jianbo.liu at arm.com>

Applied to dpdk/master, thanks.