RE: [PATCH] net/ice: support IOVA as PA mode

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Morten Brørup <mb@smartsharesystems.com>
> Sent: Monday, December 12, 2022 4:05 PM
> To: Zhang, Qi Z <qi.z.zhang@intel.com>; Richardson, Bruce
> <bruce.richardson@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>
> Cc: dev@dpdk.org; Wu, Wenjun1 <wenjun1.wu@intel.com>; Matz, Olivier
> <olivier.matz@6wind.com>
> Subject: RE: [PATCH] net/ice: support IOVA as PA mode
> 
> > From: Qi Zhang [mailto:qi.z.zhang@intel.com]
> > Sent: Monday, 12 December 2022 16.45
> > Subject: [PATCH] net/ice: support IOVA as PA mode
> 
> Typo:
> 
> "IOVA as PA mode" -> "IOVA as VA mode"
> 
> >
> > Claim pmd_supports_disable_iova_as_pa. Remove buf_iova access when
> > RTE_IOVA_AS_PA is not defined.
> >
> > The patch simply replace buf_iova with buf_addr at no IOVA as PA mode.
> 
> Please use "IOVA as VA mode" instead of "no IOVA as PA mode".
> 
> Also in the other PMD patches.
> 
> > Some SIMD instructions in data path may be over used, further
> > optimization is expected.
> >
> > Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
> > ---
> 
> [...]
> 
> > @@ -868,16 +867,12 @@ ice_vtx(volatile struct ice_tx_desc *txdp,
> >
> >  		__m256i desc2_3 =
> >  			_mm256_set_epi64x
> > -				(hi_qw3,
> > -				 pkt[3]->buf_iova + pkt[3]->data_off,
> > -				 hi_qw2,
> > -				 pkt[2]->buf_iova + pkt[2]->data_off);
> > +				(hi_qw3, _PKT_DATA_OFF_AS_U64(pkt[3]),
> > +				 hi_qw2, _PKT_DATA_OFF_AS_U64(pkt[2]));
> >  		__m256i desc0_1 =
> >  			_mm256_set_epi64x
> > -				(hi_qw1,
> > -				 pkt[1]->buf_iova + pkt[1]->data_off,
> > -				 hi_qw0,
> > -				 pkt[0]->buf_iova + pkt[0]->data_off);
> > +				(hi_qw1, _PKT_DATA_OFF_AS_U64(pkt[1]),
> > +				 hi_qw0, _PKT_DATA_OFF_AS_U64(pkt[0]));
> >  		_mm256_store_si256((void *)(txdp + 2), desc2_3);
> >  		_mm256_store_si256((void *)txdp, desc0_1);
> >  	}
> > diff --git a/drivers/net/ice/ice_rxtx_vec_avx512.c
> > b/drivers/net/ice/ice_rxtx_vec_avx512.c
> > index 5bfd5152df..e76ba1a245 100644
> > --- a/drivers/net/ice/ice_rxtx_vec_avx512.c
> > +++ b/drivers/net/ice/ice_rxtx_vec_avx512.c
> > @@ -55,9 +55,13 @@ ice_rxq_rearm(struct ice_rx_queue *rxq)
> >  			return;
> >  		}
> >  	}
> > -
> > +#if RTE_IOVA_AS_PA
> >  	const __m512i iova_offsets =  _mm512_set1_epi64
> >  		(offsetof(struct rte_mbuf, buf_iova));
> > +#else
> > +	const __m512i iova_offsets =  _mm512_set1_epi64
> > +		(offsetof(struct rte_mbuf, buf_addr)); #endif
> >  	const __m512i headroom =
> _mm512_set1_epi64(RTE_PKTMBUF_HEADROOM);
> >
> >  #ifndef RTE_LIBRTE_ICE_16BYTE_RX_DESC
> > @@ -1092,8 +1096,7 @@ ice_vtx1(volatile struct ice_tx_desc *txdp,
> >  	if (do_offload)
> >  		ice_txd_enable_offload(pkt, &high_qw);
> >
> > -	__m128i descriptor = _mm_set_epi64x(high_qw,
> > -				pkt->buf_iova + pkt->data_off);
> > +	__m128i descriptor = _mm_set_epi64x(high_qw,
> > _PKT_DATA_OFF_AS_U64(pkt));
> >  	_mm_store_si128((__m128i *)txdp, descriptor);
> >  }
> >
> > @@ -1132,14 +1135,10 @@ ice_vtx(volatile struct ice_tx_desc *txdp,
> > struct rte_mbuf **pkt,
> >
> >  		__m512i desc0_3 =
> >  			_mm512_set_epi64
> > -				(hi_qw3,
> > -				 pkt[3]->buf_iova + pkt[3]->data_off,
> > -				 hi_qw2,
> > -				 pkt[2]->buf_iova + pkt[2]->data_off,
> > -				 hi_qw1,
> > -				 pkt[1]->buf_iova + pkt[1]->data_off,
> > -				 hi_qw0,
> > -				 pkt[0]->buf_iova + pkt[0]->data_off);
> > +				(hi_qw3, _PKT_DATA_OFF_AS_U64(pkt[3]),
> > +				 hi_qw2, _PKT_DATA_OFF_AS_U64(pkt[2]),
> > +				 hi_qw1, _PKT_DATA_OFF_AS_U64(pkt[1]),
> > +				 hi_qw0, _PKT_DATA_OFF_AS_U64(pkt[0]));
> >  		_mm512_storeu_si512((void *)txdp, desc0_3);
> >  	}
> >
> > diff --git a/drivers/net/ice/ice_rxtx_vec_common.h
> > b/drivers/net/ice/ice_rxtx_vec_common.h
> > index eec6ea2134..ff530324ba 100644
> > --- a/drivers/net/ice/ice_rxtx_vec_common.h
> > +++ b/drivers/net/ice/ice_rxtx_vec_common.h
> > @@ -11,6 +11,12 @@
> >  #pragma GCC diagnostic ignored "-Wcast-qual"
> >  #endif
> >
> > +#if RTE_IOVA_AS_PA
> > +#define _PKT_DATA_OFF_AS_U64(pkt) ((pkt)->buf_iova + (pkt)->data_off)
> > +#else
> > +#define _PKT_DATA_OFF_AS_U64(pkt) ((u64)(pkt)->buf_addr + (pkt)-
> > >data_off)
> > +#endif
> > +
> 
> You should use rte_pktmbuf_iova(m) instead of defining this macro. It does
> the same.
> 
> Excellent, thank you.
> 
> Acked-by: Morten Brørup <mb@smartsharesystems.com>

Thanks, v2 has been submitted to address your comments.