[dpdk-stable] patch 'net/af_xdp: fix maximum MTU' has been queued to stable release 19.11.1

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 19.11.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 02/19/20. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Thanks.

Luca Boccassi

---
>From 4517e8b0bee0870ca82fb76d93c0ff0d914e2e63 Mon Sep 17 00:00:00 2001
From: Ciara Loftus <ciara.loftus at intel.com>
Date: Thu, 13 Feb 2020 08:49:14 +0000
Subject: [PATCH] net/af_xdp: fix maximum MTU

[ upstream commit 1668e87d4d51e9f4c333dcafa0c3e189b1eaee35 ]

The maximum MTU for af_xdp zero copy is equal to the page size less the
frame overhead introduced by AF_XDP (XDP HR = 256) and DPDK (frame
headroom = 320). The patch updates this value to reflect this.

This change also makes it possible to remove unneeded constants for both
zero-copy and copy mode.

Fixes: d8a210774e1d ("net/af_xdp: support unaligned umem chunks")

Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
Reviewed-by: Xiaolong Ye <xiaolong.ye at intel.com>
---
 drivers/net/af_xdp/rte_eth_af_xdp.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c
index 24c70473c3..d75281c10d 100644
--- a/drivers/net/af_xdp/rte_eth_af_xdp.c
+++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
@@ -59,13 +59,6 @@ static int af_xdp_logtype;
 
 #define ETH_AF_XDP_FRAME_SIZE		2048
 #define ETH_AF_XDP_NUM_BUFFERS		4096
-#ifdef XDP_UMEM_UNALIGNED_CHUNK_FLAG
-#define ETH_AF_XDP_MBUF_OVERHEAD	128 /* sizeof(struct rte_mbuf) */
-#define ETH_AF_XDP_DATA_HEADROOM \
-	(ETH_AF_XDP_MBUF_OVERHEAD + RTE_PKTMBUF_HEADROOM)
-#else
-#define ETH_AF_XDP_DATA_HEADROOM	0
-#endif
 #define ETH_AF_XDP_DFLT_NUM_DESCS	XSK_RING_CONS__DEFAULT_NUM_DESCS
 #define ETH_AF_XDP_DFLT_START_QUEUE_IDX	0
 #define ETH_AF_XDP_DFLT_QUEUE_COUNT	1
@@ -602,7 +595,14 @@ eth_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 	dev_info->max_tx_queues = internals->queue_cnt;
 
 	dev_info->min_mtu = RTE_ETHER_MIN_MTU;
-	dev_info->max_mtu = ETH_AF_XDP_FRAME_SIZE - ETH_AF_XDP_DATA_HEADROOM;
+#if defined(XDP_UMEM_UNALIGNED_CHUNK_FLAG)
+	dev_info->max_mtu = getpagesize() -
+				sizeof(struct rte_mempool_objhdr) -
+				sizeof(struct rte_mbuf) -
+				RTE_PKTMBUF_HEADROOM - XDP_PACKET_HEADROOM;
+#else
+	dev_info->max_mtu = ETH_AF_XDP_FRAME_SIZE - XDP_PACKET_HEADROOM;
+#endif
 
 	dev_info->default_rxportconf.nb_queues = 1;
 	dev_info->default_txportconf.nb_queues = 1;
@@ -804,7 +804,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
 		.fill_size = ETH_AF_XDP_DFLT_NUM_DESCS,
 		.comp_size = ETH_AF_XDP_DFLT_NUM_DESCS,
 		.frame_size = ETH_AF_XDP_FRAME_SIZE,
-		.frame_headroom = ETH_AF_XDP_DATA_HEADROOM };
+		.frame_headroom = 0 };
 	char ring_name[RTE_RING_NAMESIZE];
 	char mz_name[RTE_MEMZONE_NAMESIZE];
 	int ret;
@@ -829,8 +829,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
 
 	for (i = 0; i < ETH_AF_XDP_NUM_BUFFERS; i++)
 		rte_ring_enqueue(umem->buf_ring,
-				 (void *)(i * ETH_AF_XDP_FRAME_SIZE +
-					  ETH_AF_XDP_DATA_HEADROOM));
+				 (void *)(i * ETH_AF_XDP_FRAME_SIZE));
 
 	snprintf(mz_name, sizeof(mz_name), "af_xdp_umem_%s_%u",
 		       internals->if_name, rxq->xsk_queue_idx);
@@ -939,7 +938,7 @@ eth_rx_queue_setup(struct rte_eth_dev *dev,
 	/* Now get the space available for data in the mbuf */
 	buf_size = rte_pktmbuf_data_room_size(mb_pool) -
 		RTE_PKTMBUF_HEADROOM;
-	data_size = ETH_AF_XDP_FRAME_SIZE - ETH_AF_XDP_DATA_HEADROOM;
+	data_size = ETH_AF_XDP_FRAME_SIZE;
 
 	if (data_size > buf_size) {
 		AF_XDP_LOG(ERR, "%s: %d bytes will not fit in mbuf (%d bytes)\n",
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-02-17 17:00:16.219819347 +0000
+++ 0032-net-af_xdp-fix-maximum-MTU.patch	2020-02-17 17:00:15.347951022 +0000
@@ -1,8 +1,10 @@
-From 1668e87d4d51e9f4c333dcafa0c3e189b1eaee35 Mon Sep 17 00:00:00 2001
+From 4517e8b0bee0870ca82fb76d93c0ff0d914e2e63 Mon Sep 17 00:00:00 2001
 From: Ciara Loftus <ciara.loftus at intel.com>
 Date: Thu, 13 Feb 2020 08:49:14 +0000
 Subject: [PATCH] net/af_xdp: fix maximum MTU
 
+[ upstream commit 1668e87d4d51e9f4c333dcafa0c3e189b1eaee35 ]
+
 The maximum MTU for af_xdp zero copy is equal to the page size less the
 frame overhead introduced by AF_XDP (XDP HR = 256) and DPDK (frame
 headroom = 320). The patch updates this value to reflect this.
@@ -11,7 +13,6 @@
 zero-copy and copy mode.
 
 Fixes: d8a210774e1d ("net/af_xdp: support unaligned umem chunks")
-Cc: stable at dpdk.org
 
 Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
 Reviewed-by: Xiaolong Ye <xiaolong.ye at intel.com>
@@ -20,10 +21,10 @@
  1 file changed, 11 insertions(+), 12 deletions(-)
 
 diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c
-index a0edfc3cd3..06124ba789 100644
+index 24c70473c3..d75281c10d 100644
 --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
 +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
-@@ -58,13 +58,6 @@ static int af_xdp_logtype;
+@@ -59,13 +59,6 @@ static int af_xdp_logtype;
  
  #define ETH_AF_XDP_FRAME_SIZE		2048
  #define ETH_AF_XDP_NUM_BUFFERS		4096
@@ -37,7 +38,7 @@
  #define ETH_AF_XDP_DFLT_NUM_DESCS	XSK_RING_CONS__DEFAULT_NUM_DESCS
  #define ETH_AF_XDP_DFLT_START_QUEUE_IDX	0
  #define ETH_AF_XDP_DFLT_QUEUE_COUNT	1
-@@ -601,7 +594,14 @@ eth_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
+@@ -602,7 +595,14 @@ eth_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
  	dev_info->max_tx_queues = internals->queue_cnt;
  
  	dev_info->min_mtu = RTE_ETHER_MIN_MTU;
@@ -53,7 +54,7 @@
  
  	dev_info->default_rxportconf.nb_queues = 1;
  	dev_info->default_txportconf.nb_queues = 1;
-@@ -803,7 +803,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
+@@ -804,7 +804,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
  		.fill_size = ETH_AF_XDP_DFLT_NUM_DESCS,
  		.comp_size = ETH_AF_XDP_DFLT_NUM_DESCS,
  		.frame_size = ETH_AF_XDP_FRAME_SIZE,
@@ -62,7 +63,7 @@
  	char ring_name[RTE_RING_NAMESIZE];
  	char mz_name[RTE_MEMZONE_NAMESIZE];
  	int ret;
-@@ -828,8 +828,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
+@@ -829,8 +829,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
  
  	for (i = 0; i < ETH_AF_XDP_NUM_BUFFERS; i++)
  		rte_ring_enqueue(umem->buf_ring,
@@ -72,7 +73,7 @@
  
  	snprintf(mz_name, sizeof(mz_name), "af_xdp_umem_%s_%u",
  		       internals->if_name, rxq->xsk_queue_idx);
-@@ -938,7 +937,7 @@ eth_rx_queue_setup(struct rte_eth_dev *dev,
+@@ -939,7 +938,7 @@ eth_rx_queue_setup(struct rte_eth_dev *dev,
  	/* Now get the space available for data in the mbuf */
  	buf_size = rte_pktmbuf_data_room_size(mb_pool) -
  		RTE_PKTMBUF_HEADROOM;