ixgbe: add a callback to set the maximum transmit bitrate

This commit adds a callback which allows to adjust the maximum transmit
bitrate the card can output. This makes it possible to get a smooth
traffic instead of the default burst-y behaviour when trying to output
e.g. a video stream.

Much of the logic needed to get a correct bcnrc_val was taken from the
ixgbe_set_vf_rate_limit() function.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This commit is contained in:
Rostislav Pehlivanov 2016-01-27 18:33:30 +00:00 committed by Jeff Kirsher
parent afdc71e4d6
commit c04f90e592
3 changed files with 33 additions and 1 deletions
drivers/net/ethernet/intel/ixgbe

View File

@ -1077,6 +1077,36 @@ static void ixgbe_tx_timeout_reset(struct ixgbe_adapter *adapter)
}
}
/**
* ixgbe_tx_maxrate - callback to set the maximum per-queue bitrate
**/
static int ixgbe_tx_maxrate(struct net_device *netdev,
int queue_index, u32 maxrate)
{
struct ixgbe_adapter *adapter = netdev_priv(netdev);
struct ixgbe_hw *hw = &adapter->hw;
u32 bcnrc_val = ixgbe_link_mbps(adapter);
if (!maxrate)
return 0;
/* Calculate the rate factor values to set */
bcnrc_val <<= IXGBE_RTTBCNRC_RF_INT_SHIFT;
bcnrc_val /= maxrate;
/* clear everything but the rate factor */
bcnrc_val &= IXGBE_RTTBCNRC_RF_INT_MASK |
IXGBE_RTTBCNRC_RF_DEC_MASK;
/* enable the rate scheduler */
bcnrc_val |= IXGBE_RTTBCNRC_RS_ENA;
IXGBE_WRITE_REG(hw, IXGBE_RTTDQSEL, queue_index);
IXGBE_WRITE_REG(hw, IXGBE_RTTBCNRC, bcnrc_val);
return 0;
}
/**
* ixgbe_clean_tx_irq - Reclaim resources after transmit completes
* @q_vector: structure containing interrupt and ring information
@ -8807,6 +8837,7 @@ static const struct net_device_ops ixgbe_netdev_ops = {
.ndo_set_mac_address = ixgbe_set_mac,
.ndo_change_mtu = ixgbe_change_mtu,
.ndo_tx_timeout = ixgbe_tx_timeout,
.ndo_set_tx_maxrate = ixgbe_tx_maxrate,
.ndo_vlan_rx_add_vid = ixgbe_vlan_rx_add_vid,
.ndo_vlan_rx_kill_vid = ixgbe_vlan_rx_kill_vid,
.ndo_do_ioctl = ixgbe_ioctl,

View File

@ -1398,7 +1398,7 @@ out:
return err;
}
static int ixgbe_link_mbps(struct ixgbe_adapter *adapter)
int ixgbe_link_mbps(struct ixgbe_adapter *adapter)
{
switch (adapter->link_speed) {
case IXGBE_LINK_SPEED_100_FULL:

View File

@ -44,6 +44,7 @@ void ixgbe_ping_all_vfs(struct ixgbe_adapter *adapter);
int ixgbe_ndo_set_vf_mac(struct net_device *netdev, int queue, u8 *mac);
int ixgbe_ndo_set_vf_vlan(struct net_device *netdev, int queue, u16 vlan,
u8 qos);
int ixgbe_link_mbps(struct ixgbe_adapter *adapter);
int ixgbe_ndo_set_vf_bw(struct net_device *netdev, int vf, int min_tx_rate,
int max_tx_rate);
int ixgbe_ndo_set_vf_spoofchk(struct net_device *netdev, int vf, bool setting);