From b0e4f37b0175e60a475a6b94c2b7f010860dc357 Mon Sep 17 00:00:00 2001 From: Ioana Ciocoi Radulescu Date: Wed, 14 Nov 2018 11:48:35 +0000 Subject: [PATCH] dpaa2-eth: Don't use multiple queues per channel The DPNI object on which we build a network interface has a certain number of {Rx, Tx, Tx confirmation} frame queues as resources. The default hardware setup offers one queue of each type, as well as one DPCON channel, for each core available in the system. There are however cases where the number of queues is greater than the number of cores or channels. Until now, we configured and used all the frame queues associated with a DPNI, even if it meant assigning multiple queues of one type to the same channel. Update the driver to only use a number of queues equal to the number of channels, ensuring each channel will contain exactly one Rx and one Tx confirmation queue. >From the user viewpoint, this change is completely transparent. Performance wise there is no impact in most scenarios. In case the number of queues is larger than and not a multiple of the number of channels, Rx hash distribution offers now better load balancing between cores, which can have a positive impact on overall system performance. Signed-off-by: Ioana Radulescu Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 2 +- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index bdfb13b71998..7a4a315fc1aa 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -1603,7 +1603,7 @@ static int setup_dpio(struct dpaa2_eth_priv *priv) /* Stop if we already have enough channels to accommodate all * RX and TX conf queues */ - if (priv->num_channels == dpaa2_eth_queue_count(priv)) + if (priv->num_channels == priv->dpni_attrs.num_queues) break; } diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h index 452a8e9c4f0e..b7837cf01a5d 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h @@ -434,9 +434,10 @@ static inline unsigned int dpaa2_eth_rx_head_room(struct dpaa2_eth_priv *priv) DPAA2_ETH_RX_HWA_SIZE; } +/* We have exactly one {Rx, Tx conf} queue per channel */ static int dpaa2_eth_queue_count(struct dpaa2_eth_priv *priv) { - return priv->dpni_attrs.num_queues; + return priv->num_channels; } int dpaa2_eth_set_hash(struct net_device *net_dev, u64 flags); -- 2.30.2