[dpdk-dev] [PATCH v4 12/17] net/virtio: add checks for max SIMD bitwidth

Ciara Power ciara.power at intel.com
Tue Oct 13 12:38:12 CEST 2020


When choosing a vector path to take, an extra condition must be
satisfied to ensure the max SIMD bitwidth allows for the CPU enabled
path.

Cc: Maxime Coquelin <maxime.coquelin at redhat.com>
Cc: Chenbo Xia <chenbo.xia at intel.com>
Cc: Zhihong Wang <zhihong.wang at intel.com>

Signed-off-by: Ciara Power <ciara.power at intel.com>

---
v4: Updated enum name.
v3: Moved max SIMD bitwidth check to configure function with other vec
    support checks.
---
 drivers/net/virtio/virtio_ethdev.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 0236c756dc..70955e5cc0 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -2313,7 +2313,8 @@ virtio_dev_configure(struct rte_eth_dev *dev)
 		if ((hw->use_vec_rx || hw->use_vec_tx) &&
 		    (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX512F) ||
 		     !vtpci_with_feature(hw, VIRTIO_F_IN_ORDER) ||
-		     !vtpci_with_feature(hw, VIRTIO_F_VERSION_1))) {
+		     !vtpci_with_feature(hw, VIRTIO_F_VERSION_1) ||
+		     rte_get_max_simd_bitwidth() < RTE_SIMD_512)) {
 			PMD_DRV_LOG(INFO,
 				"disabled packed ring vectorized path for requirements not met");
 			hw->use_vec_rx = 0;
@@ -2366,6 +2367,12 @@ virtio_dev_configure(struct rte_eth_dev *dev)
 					"disabled split ring vectorized rx for offloading enabled");
 				hw->use_vec_rx = 0;
 			}
+
+			if (rte_get_max_simd_bitwidth() < RTE_SIMD_128) {
+				PMD_DRV_LOG(INFO,
+					"disabled split ring vectorized rx, max SIMD bitwidth too low");
+				hw->use_vec_rx = 0;
+			}
 		}
 	}
 
-- 
2.22.0



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