Re: [dpdk-dev] [PATCH v2] net/virtio: fix compiling issue for vectorized NEON path

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 1/27/21 11:37 AM, Subhi Masri wrote:
> Hi,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Sent: Wednesday, January 27, 2021 10:44 AM
>> To: Subhi Masri <subhim@nvidia.com>
>> Cc: dev@dpdk.org; nd@arm.com; Joyce Kong <joyce.kong@arm.com>;
>> david.marchand@redhat.com; honnappa.nagarahalli@arm.com;
>> ruifeng.wang@arm.com; i.maximets@ovn.org
>> Subject: Re: [PATCH v2] net/virtio: fix compiling issue for vectorized NEON
>> path
>>
>> External email: Use caution opening links or attachments
>>
>>
>> Hi Subhi,
>>
>> On 1/26/21 10:57 AM, Joyce Kong wrote:
>>> In file included from ../drivers/net/virtio/virtio_rxtx_packed.c:22:0:
>>> ../drivers/net/virtio/virtio_rxtx_packed_neon.h: In function
>>> ‘virtqueue_enqueue_batch_packed_vec’:
>>> ../drivers/net/virtio/virtio_rxtx_packed_neon.h:74:2: warning:
>>> implicit declaration of function ‘vreinterpretq_p128_u32’
>>> [-Wimplicit-function-declaration]
>>> poly128_t cmp1 = vreinterpretq_p128_u32(~vceqq_u32(ref_seg,
>>> def_ref_seg)); ^
>>>
>>> The message shows ‘vreinterpretq_p128_u32’ intrinsic is not supported
>>> because an old version gcc (gcc 4.8.5) is used. So fix the issue with
>>> implementing the logic with other intrinsics.
>>>
>>> Bugzilla ID: 621
>>> Fixes: 530887469350 ("net/virtio: add vectorized packed ring NEON Tx")
>>> Fixes: 5971ce5e2a59 ("net/virtio: add vectorized packed ring NEON Rx")
>>>
>>> Reported-by: Subhi Masri <subhim@nvidia.com>
>>> Signed-off-by: Joyce Kong <joyce.kong@arm.com>
>>> ---
>>>  drivers/net/virtio/virtio_rxtx_packed_neon.h | 8 ++++----
>>>  1 file changed, 4 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/net/virtio/virtio_rxtx_packed_neon.h
>>> b/drivers/net/virtio/virtio_rxtx_packed_neon.h
>>> index 01c77b712..00dd04277 100644
>>> --- a/drivers/net/virtio/virtio_rxtx_packed_neon.h
>>> +++ b/drivers/net/virtio/virtio_rxtx_packed_neon.h
>>> @@ -71,8 +71,8 @@ virtqueue_enqueue_batch_packed_vec(struct
>> virtnet_tx *txvq,
>>>       uint32x4_t def_ref_seg = vdupq_n_u32(0x10001);
>>>       /* Check refcnt and nb_segs. */
>>>       uint32x4_t ref_seg = vreinterpretq_u32_u8(vqtbl2q_u8(mbuf,
>> ref_seg_msk));
>>> -     poly128_t cmp1 = vreinterpretq_p128_u32(~vceqq_u32(ref_seg,
>> def_ref_seg));
>>> -     if (unlikely(cmp1))
>>> +     uint64x2_t cmp1 = vreinterpretq_u64_u32(~vceqq_u32(ref_seg,
>> def_ref_seg));
>>> +     if (unlikely(vgetq_lane_u64(cmp1, 0) || vgetq_lane_u64(cmp1,
>>> + 1)))
>>>               return -1;
>>>
>>>       /* Check headroom is enough. */
>>> @@ -225,10 +225,10 @@ virtqueue_dequeue_batch_packed_vec(struct
>> virtnet_rx *rxvq,
>>>       if (vq->vq_packed.used_wrap_counter)
>>>               v_used_flag = vdupq_n_u32(PACKED_FLAGS_MASK);
>>>
>>> -     poly128_t desc_stats = vreinterpretq_p128_u32(~vceqq_u32(v_flag,
>> v_used_flag));
>>> +     uint64x2_t desc_stats = vreinterpretq_u64_u32(~vceqq_u32(v_flag,
>>> + v_used_flag));
>>>
>>>       /* Check all descs are used. */
>>> -     if (desc_stats)
>>> +     if (unlikely(vgetq_lane_u64(desc_stats, 0) ||
>>> + vgetq_lane_u64(desc_stats, 1)))
>>>               return -1;
>>>
>>>       /* Load 2 mbuf pointers per time. */
>>>
>>
>> Can you confirm the patch works for you?
>>
> Yes it does , you can add my tag.
> Tested-by: Subhi Masri <subhim@nvidia.com>

Thanks!
Maxime

>> Thanks,
>> Maxime
> 
> 
> Regards,
> Subhi Masri
>