diff mbox

[dpdk-dev,v2] net/thunderx: check data offset alignment requirement

Message ID 1489392131-9293-1-git-send-email-jerin.jacob@caviumnetworks.com (mailing list archive)
State Accepted, archived
Delegated to: Ferruh Yigit
Headers

Checks

Context Check Description
ci/Intel-compilation success Compilation OK
ci/checkpatch success coding style OK

Commit Message

Jerin Jacob March 13, 2017, 8:02 a.m. UTC 
  nicvf HW expects the DMA address of the packet data to be
aligned with cache line size.

Packet data offset is a function of struct mbuf size,
mbuf private size and headroom. mbuf private size can
be changed from the application in pool creation, this
check detects HW alignment requirement constraint in pmd
start function.

Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>
---
v2:
Add pool name in error log(Hemant)
---
 drivers/net/thunderx/nicvf_ethdev.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Comments

Ferruh Yigit March 14, 2017, 3:39 p.m. UTC | #1 
On 3/13/2017 8:02 AM, Jerin Jacob wrote:
> nicvf HW expects the DMA address of the packet data to be
> aligned with cache line size.
> 
> Packet data offset is a function of struct mbuf size,
> mbuf private size and headroom. mbuf private size can
> be changed from the application in pool creation, this
> check detects HW alignment requirement constraint in pmd
> start function.
> 
> Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
> Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>

Applied to dpdk-next-net/master, thanks.
diff mbox

Patch

diff --git a/drivers/net/thunderx/nicvf_ethdev.c b/drivers/net/thunderx/nicvf_ethdev.c
index fa1cb32..5f34237 100644
--- a/drivers/net/thunderx/nicvf_ethdev.c
+++ b/drivers/net/thunderx/nicvf_ethdev.c
@@ -1409,7 +1409,7 @@  static int
 nicvf_vf_start(struct rte_eth_dev *dev, struct nicvf *nic, uint32_t rbdrsz)
 {
 	int ret;
-	uint16_t qidx;
+	uint16_t qidx, data_off;
 	uint32_t total_rxq_desc, nb_rbdr_desc, exp_buffs;
 	uint64_t mbuf_phys_off = 0;
 	struct nicvf_rxq *rxq;
@@ -1450,10 +1450,18 @@  nicvf_vf_start(struct rte_eth_dev *dev, struct nicvf *nic, uint32_t rbdrsz)
 				     nic->vf_id, qidx, rxq->pool->name);
 			return -ENOMEM;
 		}
-		rxq->mbuf_phys_off -= nicvf_mbuff_meta_length(mbuf);
-		rxq->mbuf_phys_off -= RTE_PKTMBUF_HEADROOM;
+		data_off = nicvf_mbuff_meta_length(mbuf);
+		data_off += RTE_PKTMBUF_HEADROOM;
 		rte_pktmbuf_free(mbuf);
 
+		if (data_off % RTE_CACHE_LINE_SIZE) {
+			PMD_INIT_LOG(ERR, "%s: unaligned data_off=%d delta=%d",
+				rxq->pool->name, data_off,
+				data_off % RTE_CACHE_LINE_SIZE);
+			return -EINVAL;
+		}
+		rxq->mbuf_phys_off -= data_off;
+
 		if (mbuf_phys_off == 0)
 			mbuf_phys_off = rxq->mbuf_phys_off;
 		if (mbuf_phys_off != rxq->mbuf_phys_off) {