diff options
author | Tariq Toukan <tariqt@mellanox.com> | 2017-06-15 14:35:37 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-06-16 05:53:23 +0300 |
commit | 6c78511b0503c9b53fd0f5ccc8b28d5e94a3dfcb (patch) | |
tree | 3e1e040b393aa76fb287bc8c6b13775b653324f6 /drivers/net/ethernet/mellanox/mlx4/en_netdev.c | |
parent | 36ea7964982f54370e051386b74df914c53e2219 (diff) | |
download | linux-6c78511b0503c9b53fd0f5ccc8b28d5e94a3dfcb.tar.xz |
net/mlx4_en: Poll XDP TX completion queue in RX NAPI
Instead of having their own NAPIs, XDP TX completion queues get
polled within the corresponding RX NAPI.
This prevents any possible race on TX ring prod/cons indices,
between the context that issues the transmits (RX NAPI) and the
context that handles the completions (was previously done in
a separate NAPI).
This also improves performance, as it decreases the number
of NAPIs running on a CPU, saving the overhead of syncing
and switching between the contexts.
Performance tests:
Tested on ConnectX3Pro, Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
Single queue no-RSS optimization ON.
XDP_TX packet rate:
-------------------------------------
| Before | After | Gain |
IPv4 | 12.0 Mpps | 13.8 Mpps | 15% |
IPv6 | 12.0 Mpps | 13.8 Mpps | 15% |
-------------------------------------
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Cc: kernel-team@fb.com
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx4/en_netdev.c')
-rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c index 51ce111b719e..99c02bb4f302 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c @@ -1679,13 +1679,15 @@ int mlx4_en_start_port(struct net_device *dev) if (t != TX_XDP) { tx_ring->tx_queue = netdev_get_tx_queue(dev, i); tx_ring->recycle_ring = NULL; + + /* Arm CQ for TX completions */ + mlx4_en_arm_cq(priv, cq); + } else { mlx4_en_init_recycle_ring(priv, i); + /* XDP TX CQ should never be armed */ } - /* Arm CQ for TX completions */ - mlx4_en_arm_cq(priv, cq); - /* Set initial ownership of all Tx TXBBs to SW (1) */ for (j = 0; j < tx_ring->buf_size; j += STAMP_STRIDE) *((u32 *)(tx_ring->buf + j)) = 0xffffffff; |