[dpdk-dev] [PATCH v2 0/2] net/i40e: improve free mbuf for Tx

[dpdk-dev] [PATCH v2 0/2] net/i40e: improve free mbuf for Tx

[Feifei Wang]

For i40e Tx path, use bulk free of the buffers when mbuf fast free
mode is enabled. This can efficiently improve the performance.

v2:
1. fix bug when tx_rs_thres > RTE_I40E_TX_MAX_FREE_BUF_SZ (Beilei)

Feifei Wang (2):
  net/i40e: improve performance for scalar Tx
  net/i40e: improve performance for vector Tx

 drivers/net/i40e/i40e_rxtx.c            | 26 +++++++++++++++++++++----
 drivers/net/i40e/i40e_rxtx_vec_common.h | 11 +++++++++++
 2 files changed, 33 insertions(+), 4 deletions(-)

-- 
2.25.1

[dpdk-dev] [PATCH v2 1/2] net/i40e: improve performance for scalar Tx

[Feifei Wang]

For i40e scalar Tx path, if implement FAST_FREE_MBUF mode, it means
per-queue all mbufs come from the same mempool and have refcnt = 1.

Thus we can use bulk free of the buffers when mbuf fast free mode is
enabled.

Following are the test results with this patch:

MRR L3FWD Test:
two ports & bi-directional flows & one core
RX API: i40e_recv_pkts_bulk_alloc
TX API: i40e_xmit_pkts_simple
ring_descs_size = 1024;
Ring_I40E_TX_MAX_FREE_SZ = 64;
tx_rs_thresh = I40E_DEFAULT_TX_RSBIT_THRESH = 32;
tx_free_thresh = I40E_DEFAULT_TX_FREE_THRESH = 32;

For scalar path in arm platform with default 'tx_rs_thresh':
In n1sdp, performance is improved by 7.9%;
In thunderx2, performance is improved by 7.6%.

For scalar path in x86 platform with default 'tx_rs_thresh':
performance is improved by 4.7%.

Suggested-by: Ruifeng Wang <ruifeng.wang@arm.com>
Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
 drivers/net/i40e/i40e_rxtx.c | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
index 6c58decece..8c72391cde 100644
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -1294,7 +1294,11 @@ static __rte_always_inline int
 i40e_tx_free_bufs(struct i40e_tx_queue *txq)
 {
 	struct i40e_tx_entry *txep;
-	uint16_t i;
+	int n = txq->tx_rs_thresh;
+	uint16_t i = 0, j = 0;
+	struct rte_mbuf *free[RTE_I40E_TX_MAX_FREE_BUF_SZ];
+	const int32_t k = RTE_ALIGN_FLOOR(n, RTE_I40E_TX_MAX_FREE_BUF_SZ);
+	const int32_t m = n % RTE_I40E_TX_MAX_FREE_BUF_SZ;
 
 	if ((txq->tx_ring[txq->tx_next_dd].cmd_type_offset_bsz &
 			rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) !=
@@ -1307,9 +1311,23 @@ i40e_tx_free_bufs(struct i40e_tx_queue *txq)
 		rte_prefetch0((txep + i)->mbuf);
 
 	if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE) {
-		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
-			rte_mempool_put(txep->mbuf->pool, txep->mbuf);
-			txep->mbuf = NULL;
+		if (k) {
+			for (j = 0; j != k; j += RTE_I40E_TX_MAX_FREE_BUF_SZ) {
+				for (i = 0; i < RTE_I40E_TX_MAX_FREE_BUF_SZ; ++i, ++txep) {
+					free[i] = txep->mbuf;
+					txep->mbuf = NULL;
+				}
+				rte_mempool_put_bulk(free[0]->pool, (void **)free,
+						RTE_I40E_TX_MAX_FREE_BUF_SZ);
+			}
+		}
+
+		if (m) {
+			for (i = 0; i < m; ++i, ++txep) {
+				free[i] = txep->mbuf;
+				txep->mbuf = NULL;
+			}
+			rte_mempool_put_bulk(free[0]->pool, (void **)free, m);
 		}
 	} else {
 		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
-- 
2.25.1

[dpdk-dev] [PATCH v2 2/2] net/i40e: improve performance for vector Tx

[Feifei Wang]

For i40e vector Tx path, if tx_offload is set as FAST_FREE_MBUF mode,
no mbuf fast free operations are executed. To fix this, add mbuf fast
free mode for vector Tx path.

Furthermore, for i40e vector Tx path, if implement FAST_FREE_MBUF mode,
it means per-queue all mbufs come from the same mempool and have
refcnt = 1. Thus we can use bulk free of the buffers when mbuf fast free
mode is enabled.

For vector path in arm platform:
In n1sdp, performance is improved by 18.4%;
In thunderx2, performance is improved by 23%.

For vector path in x86 platform:
No performance changes.

Suggested-by: Ruifeng Wang <ruifeng.wang@arm.com>
Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
 drivers/net/i40e/i40e_rxtx_vec_common.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/i40e/i40e_rxtx_vec_common.h b/drivers/net/i40e/i40e_rxtx_vec_common.h
index 16fcf0aec6..f52ed98d62 100644
--- a/drivers/net/i40e/i40e_rxtx_vec_common.h
+++ b/drivers/net/i40e/i40e_rxtx_vec_common.h
@@ -99,6 +99,16 @@ i40e_tx_free_bufs(struct i40e_tx_queue *txq)
 	  * tx_next_dd - (tx_rs_thresh-1)
 	  */
 	txep = &txq->sw_ring[txq->tx_next_dd - (n - 1)];
+
+	if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE) {
+		for (i = 0; i < n; i++) {
+			free[i] = txep[i].mbuf;
+			txep[i].mbuf = NULL;
+		}
+		rte_mempool_put_bulk(free[0]->pool, (void **)free, n);
+		goto done;
+	}
+
 	m = rte_pktmbuf_prefree_seg(txep[0].mbuf);
 	if (likely(m != NULL)) {
 		free[0] = m;
@@ -126,6 +136,7 @@ i40e_tx_free_bufs(struct i40e_tx_queue *txq)
 		}
 	}
 
+done:
 	/* buffers were freed, update counters */
 	txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + txq->tx_rs_thresh);
 	txq->tx_next_dd = (uint16_t)(txq->tx_next_dd + txq->tx_rs_thresh);
-- 
2.25.1

Re: [dpdk-dev] [PATCH v2 1/2] net/i40e: improve performance for scalar Tx

[Xing, Beilei]

> -----Original Message-----
> From: Feifei Wang <feifei.wang2@arm.com>
> Sent: Wednesday, June 30, 2021 10:04 AM
> To: Xing, Beilei <beilei.xing@intel.com>
> Cc: dev@dpdk.org; nd@arm.com; Feifei Wang <feifei.wang2@arm.com>;
> Ruifeng Wang <ruifeng.wang@arm.com>
> Subject: [PATCH v2 1/2] net/i40e: improve performance for scalar Tx
> 
> For i40e scalar Tx path, if implement FAST_FREE_MBUF mode, it means per-
> queue all mbufs come from the same mempool and have refcnt = 1.
> 
> Thus we can use bulk free of the buffers when mbuf fast free mode is
> enabled.
> 
> Following are the test results with this patch:
> 
> MRR L3FWD Test:
> two ports & bi-directional flows & one core RX API:
> i40e_recv_pkts_bulk_alloc TX API: i40e_xmit_pkts_simple ring_descs_size =
> 1024; Ring_I40E_TX_MAX_FREE_SZ = 64; tx_rs_thresh =
> I40E_DEFAULT_TX_RSBIT_THRESH = 32; tx_free_thresh =
> I40E_DEFAULT_TX_FREE_THRESH = 32;
> 
> For scalar path in arm platform with default 'tx_rs_thresh':
> In n1sdp, performance is improved by 7.9%; In thunderx2, performance is
> improved by 7.6%.
> 
> For scalar path in x86 platform with default 'tx_rs_thresh':
> performance is improved by 4.7%.
> 
> Suggested-by: Ruifeng Wang <ruifeng.wang@arm.com>
> Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> ---
>  drivers/net/i40e/i40e_rxtx.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c index
> 6c58decece..8c72391cde 100644
> --- a/drivers/net/i40e/i40e_rxtx.c
> +++ b/drivers/net/i40e/i40e_rxtx.c
> @@ -1294,7 +1294,11 @@ static __rte_always_inline int
> i40e_tx_free_bufs(struct i40e_tx_queue *txq)  {
>  	struct i40e_tx_entry *txep;
> -	uint16_t i;
> +	int n = txq->tx_rs_thresh;

Thanks for the patch, just little comment, can we use 'tx_rs_thresh' to replace 'n' to make it more readable?

> +	uint16_t i = 0, j = 0;
> +	struct rte_mbuf *free[RTE_I40E_TX_MAX_FREE_BUF_SZ];
> +	const int32_t k = RTE_ALIGN_FLOOR(n,
> RTE_I40E_TX_MAX_FREE_BUF_SZ);
> +	const int32_t m = n % RTE_I40E_TX_MAX_FREE_BUF_SZ;
> 
>  	if ((txq->tx_ring[txq->tx_next_dd].cmd_type_offset_bsz &
>  			rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) !=
> @@ -1307,9 +1311,23 @@ i40e_tx_free_bufs(struct i40e_tx_queue *txq)
>  		rte_prefetch0((txep + i)->mbuf);
> 
>  	if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE) {
> -		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
> -			rte_mempool_put(txep->mbuf->pool, txep->mbuf);
> -			txep->mbuf = NULL;
> +		if (k) {
> +			for (j = 0; j != k; j += RTE_I40E_TX_MAX_FREE_BUF_SZ)
> {
> +				for (i = 0; i < RTE_I40E_TX_MAX_FREE_BUF_SZ;
> ++i, ++txep) {
> +					free[i] = txep->mbuf;
> +					txep->mbuf = NULL;
> +				}
> +				rte_mempool_put_bulk(free[0]->pool, (void
> **)free,
> +
> 	RTE_I40E_TX_MAX_FREE_BUF_SZ);
> +			}
> +		}
> +
> +		if (m) {
> +			for (i = 0; i < m; ++i, ++txep) {
> +				free[i] = txep->mbuf;
> +				txep->mbuf = NULL;
> +			}
> +			rte_mempool_put_bulk(free[0]->pool, (void **)free,
> m);
>  		}
>  	} else {
>  		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
> --
> 2.25.1

[dpdk-dev] 回复: [PATCH v2 1/2] net/i40e: improve performance for scalar Tx

[Feifei Wang]

> -----邮件原件-----
> 发件人: Xing, Beilei <beilei.xing@intel.com>
> 发送时间: 2021年6月30日 11:43
> 收件人: Feifei Wang <Feifei.Wang2@arm.com>
> 抄送: dev@dpdk.org; nd <nd@arm.com>; Ruifeng Wang
> <Ruifeng.Wang@arm.com>
> 主题: RE: [PATCH v2 1/2] net/i40e: improve performance for scalar Tx
> 
> 
> 
> > -----Original Message-----
> > From: Feifei Wang <feifei.wang2@arm.com>
> > Sent: Wednesday, June 30, 2021 10:04 AM
> > To: Xing, Beilei <beilei.xing@intel.com>
> > Cc: dev@dpdk.org; nd@arm.com; Feifei Wang <feifei.wang2@arm.com>;
> > Ruifeng Wang <ruifeng.wang@arm.com>
> > Subject: [PATCH v2 1/2] net/i40e: improve performance for scalar Tx
> >
> > For i40e scalar Tx path, if implement FAST_FREE_MBUF mode, it means
> > per- queue all mbufs come from the same mempool and have refcnt = 1.
> >
> > Thus we can use bulk free of the buffers when mbuf fast free mode is
> > enabled.
> >
> > Following are the test results with this patch:
> >
> > MRR L3FWD Test:
> > two ports & bi-directional flows & one core RX API:
> > i40e_recv_pkts_bulk_alloc TX API: i40e_xmit_pkts_simple
> > ring_descs_size = 1024; Ring_I40E_TX_MAX_FREE_SZ = 64; tx_rs_thresh =
> > I40E_DEFAULT_TX_RSBIT_THRESH = 32; tx_free_thresh =
> > I40E_DEFAULT_TX_FREE_THRESH = 32;
> >
> > For scalar path in arm platform with default 'tx_rs_thresh':
> > In n1sdp, performance is improved by 7.9%; In thunderx2, performance
> > is improved by 7.6%.
> >
> > For scalar path in x86 platform with default 'tx_rs_thresh':
> > performance is improved by 4.7%.
> >
> > Suggested-by: Ruifeng Wang <ruifeng.wang@arm.com>
> > Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
> > Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> > ---
> >  drivers/net/i40e/i40e_rxtx.c | 26 ++++++++++++++++++++++----
> >  1 file changed, 22 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/net/i40e/i40e_rxtx.c
> > b/drivers/net/i40e/i40e_rxtx.c index 6c58decece..8c72391cde 100644
> > --- a/drivers/net/i40e/i40e_rxtx.c
> > +++ b/drivers/net/i40e/i40e_rxtx.c
> > @@ -1294,7 +1294,11 @@ static __rte_always_inline int
> > i40e_tx_free_bufs(struct i40e_tx_queue *txq)  {
> >  	struct i40e_tx_entry *txep;
> > -	uint16_t i;
> > +	int n = txq->tx_rs_thresh;
> 
> Thanks for the patch, just little comment, can we use 'tx_rs_thresh' to
> replace 'n' to make it more readable?
Good comments for this, I will update it, thanks.

> 
> > +	uint16_t i = 0, j = 0;
> > +	struct rte_mbuf *free[RTE_I40E_TX_MAX_FREE_BUF_SZ];
> > +	const int32_t k = RTE_ALIGN_FLOOR(n,
> > RTE_I40E_TX_MAX_FREE_BUF_SZ);
> > +	const int32_t m = n % RTE_I40E_TX_MAX_FREE_BUF_SZ;
> >
> >  	if ((txq->tx_ring[txq->tx_next_dd].cmd_type_offset_bsz &
> >
> 	rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) != @@ -1307,9
> +1311,23
> > @@ i40e_tx_free_bufs(struct i40e_tx_queue *txq)
> >  		rte_prefetch0((txep + i)->mbuf);
> >
> >  	if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE) {
> > -		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
> > -			rte_mempool_put(txep->mbuf->pool, txep->mbuf);
> > -			txep->mbuf = NULL;
> > +		if (k) {
> > +			for (j = 0; j != k; j +=
> RTE_I40E_TX_MAX_FREE_BUF_SZ)
> > {
> > +				for (i = 0; i <
> RTE_I40E_TX_MAX_FREE_BUF_SZ;
> > ++i, ++txep) {
> > +					free[i] = txep->mbuf;
> > +					txep->mbuf = NULL;
> > +				}
> > +				rte_mempool_put_bulk(free[0]->pool, (void
> > **)free,
> > +
> > 	RTE_I40E_TX_MAX_FREE_BUF_SZ);
> > +			}
> > +		}
> > +
> > +		if (m) {
> > +			for (i = 0; i < m; ++i, ++txep) {
> > +				free[i] = txep->mbuf;
> > +				txep->mbuf = NULL;
> > +			}
> > +			rte_mempool_put_bulk(free[0]->pool, (void **)free,
> > m);
> >  		}
> >  	} else {
> >  		for (i = 0; i < txq->tx_rs_thresh; ++i, ++txep) {
> > --
> > 2.25.1