[dpdk-dev] [PATCH] i40e: enable i40e pmd on ARM platform

[Yao, Lei A]

Hi, Jianbo

I have tested you patch on my X86 platform,  the single core performance for Non-vector PMD will have about 1Mpps drop
Non-vector PMD single core performance with patch               :  ~33.9 Mpps
Non-vector PMD single core performance without patch        :  ~35.1 Mpps
Is there any way to avoid such performance drop on X86? Thanks.

BRs
Lei

-----Original Message-----
From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Jianbo Liu
Sent: Tuesday, August 2, 2016 2:58 PM
To: dev at dpdk.org; Zhang, Helin <helin.zhang at intel.com>; Wu, Jingjing <jingjing.wu at intel.com>
Cc: Jianbo Liu <jianbo.liu at linaro.org>
Subject: [dpdk-dev] [PATCH] i40e: enable i40e pmd on ARM platform

And add read memory barrier to avoid status inconsistency between two RX descriptors readings.

Signed-off-by: Jianbo Liu <jianbo.liu at linaro.org>
---
 config/defconfig_arm64-armv8a-linuxapp-gcc | 2 +-
 doc/guides/nics/overview.rst               | 2 +-
 drivers/net/i40e/i40e_rxtx.c               | 2 ++
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/config/defconfig_arm64-armv8a-linuxapp-gcc b/config/defconfig_arm64-armv8a-linuxapp-gcc
index 1a17126..08f282b 100644
--- a/config/defconfig_arm64-armv8a-linuxapp-gcc
+++ b/config/defconfig_arm64-armv8a-linuxapp-gcc
@@ -46,6 +46,6 @@ CONFIG_RTE_EAL_IGB_UIO=n
 
 CONFIG_RTE_LIBRTE_IVSHMEM=n
 CONFIG_RTE_LIBRTE_FM10K_PMD=n
-CONFIG_RTE_LIBRTE_I40E_PMD=n
+CONFIG_RTE_LIBRTE_I40E_INC_VECTOR=n
 
 CONFIG_RTE_SCHED_VECTOR=n
diff --git a/doc/guides/nics/overview.rst b/doc/guides/nics/overview.rst index 6abbae6..5175591 100644
--- a/doc/guides/nics/overview.rst
+++ b/doc/guides/nics/overview.rst
@@ -138,7 +138,7 @@ Most of these differences are summarized below.
    Linux VFIO                     Y Y   Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y                     Y   Y Y
    Other kdrv                                                         Y Y               Y
    ARMv7                                                                        Y             Y Y
-   ARMv8                                              Y Y Y Y                   Y         Y   Y Y
+   ARMv8                                  Y           Y Y Y Y                   Y         Y   Y Y
    Power8                                                             Y Y       Y
    TILE-Gx                                                                      Y
    x86-32                         Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y       Y           Y Y Y
diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c index 554d167..4004b8e 100644
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -994,6 +994,8 @@ i40e_rx_scan_hw_ring(struct i40e_rx_queue *rxq)
 					I40E_RXD_QW1_STATUS_SHIFT;
 		}
 
+		rte_rmb();
+
 		/* Compute how many status bits were set */
 		for (j = 0, nb_dd = 0; j < I40E_LOOK_AHEAD; j++)
 			nb_dd += s[j] & (1 << I40E_RX_DESC_STATUS_DD_SHIFT);
--
2.4.11