diff options
| author | Ido Shamay <idos@mellanox.com> | 2014-02-21 14:39:18 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-02-25 03:38:14 +0400 |
| commit | bb2146bc883e86b835e30644757a6d4a649a7ce8 (patch) | |
| tree | 4d3cd829ab33089beed742531dd28b02db5a12ea /drivers/net/ethernet | |
| parent | 02512482321c531df4abf73943529f8b44d869e2 (diff) | |
| download | linux-bb2146bc883e86b835e30644757a6d4a649a7ce8.tar.xz | |
net/mlx4: Fix limiting number of IRQ's instead of RSS queues
This fix a performance bug introduced by commit 90b1ebe "mlx4: set
maximal number of default RSS queues", which limits the numbers of IRQs
opened by core module.
The limit should be on the number of queues in the indirection table -
rx_rings, and not on the number of IRQ's. Also, limiting on mlx4_core
initialization instead of in mlx4_en, prevented using "ethtool -L" to
utilize all the CPU's, when performance mode is prefered, since limiting
this number to 8 reduces overall packet rate by 15%-50% in multiple TCP
streams applications.
For example, after running ethtool -L <ethx> rx 16
Packet rate
Before the fix 897799
After the fix 1142070
Results were obtained using netperf:
S=200 ; ( for i in $(seq 1 $S) ; do ( \
netperf -H 11.7.13.55 -t TCP_RR -l 30 &) ; \
wait ; done | grep "1 1" | awk '{SUM+=$6} END {print SUM}' )
CC: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_rx.c | 5 | ||||
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/main.c | 3 |
2 files changed, 5 insertions, 3 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index 85434d73c9bc..8afb72ec957d 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -322,6 +322,7 @@ void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev) { int i; int num_of_eqs; + int num_rx_rings; struct mlx4_dev *dev = mdev->dev; mlx4_foreach_port(i, dev, MLX4_PORT_TYPE_ETH) { @@ -335,8 +336,10 @@ void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev) dev->caps.comp_pool/ dev->caps.num_ports) - 1; + num_rx_rings = min_t(int, num_of_eqs, + netif_get_num_default_rss_queues()); mdev->profile.prof[i].rx_ring_num = - rounddown_pow_of_two(num_of_eqs); + rounddown_pow_of_two(num_rx_rings); } } diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c index 218b759c506e..979ea4364efb 100644 --- a/drivers/net/ethernet/mellanox/mlx4/main.c +++ b/drivers/net/ethernet/mellanox/mlx4/main.c @@ -41,7 +41,6 @@ #include <linux/slab.h> #include <linux/io-mapping.h> #include <linux/delay.h> -#include <linux/netdevice.h> #include <linux/kmod.h> #include <linux/mlx4/device.h> @@ -1974,7 +1973,7 @@ static void mlx4_enable_msi_x(struct mlx4_dev *dev) struct mlx4_priv *priv = mlx4_priv(dev); struct msix_entry *entries; int nreq = min_t(int, dev->caps.num_ports * - min_t(int, netif_get_num_default_rss_queues() + 1, + min_t(int, num_online_cpus() + 1, MAX_MSIX_P_PORT) + MSIX_LEGACY_SZ, MAX_MSIX); int i; |