hv_netvsc: Implement set_channels ethtool op

This enables the use of ethtool --set-channels devname combined N to
change the number of vRSS queues. Separate rx, tx, and other parameters
are not supported. The maximum is rsscap.num_recv_que. It passes the
given value to rndis_filter_device_add through the device_info->num_chn
field.

If the procedure fails, it attempts to recover to the prior state. If
the recovery fails, it logs an error and aborts.

Current num_chn is saved and restored when changing the MTU.

Signed-off-by: Andrew Schwartzmeyer <andschwa@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Andrew Schwartzmeyer 2015-08-11 17:14:32 -07:00 committed by David S. Miller
parent 8ebdcc52b9
commit b5960e6e2b
1 changed files with 97 additions and 0 deletions

View File

@ -770,6 +770,101 @@ static void netvsc_get_channels(struct net_device *net,
}
}
static int netvsc_set_channels(struct net_device *net,
struct ethtool_channels *channels)
{
struct net_device_context *net_device_ctx = netdev_priv(net);
struct hv_device *dev = net_device_ctx->device_ctx;
struct netvsc_device *nvdev = hv_get_drvdata(dev);
struct netvsc_device_info device_info;
const u32 num_chn = nvdev->num_chn;
const u32 max_chn = min_t(u32, nvdev->max_chn, num_online_cpus());
int ret = 0;
bool recovering = false;
if (!nvdev || nvdev->destroy)
return -ENODEV;
if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5) {
pr_info("vRSS unsupported before NVSP Version 5\n");
return -EINVAL;
}
/* We do not support rx, tx, or other */
if (!channels ||
channels->rx_count ||
channels->tx_count ||
channels->other_count ||
(channels->combined_count < 1))
return -EINVAL;
if (channels->combined_count > max_chn) {
pr_info("combined channels too high, using %d\n", max_chn);
channels->combined_count = max_chn;
}
ret = netvsc_close(net);
if (ret)
goto out;
do_set:
nvdev->start_remove = true;
rndis_filter_device_remove(dev);
nvdev->num_chn = channels->combined_count;
net_device_ctx->device_ctx = dev;
hv_set_drvdata(dev, net);
memset(&device_info, 0, sizeof(device_info));
device_info.num_chn = nvdev->num_chn; /* passed to RNDIS */
device_info.ring_size = ring_size;
device_info.max_num_vrss_chns = max_num_vrss_chns;
ret = rndis_filter_device_add(dev, &device_info);
if (ret) {
if (recovering) {
netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
return ret;
}
goto recover;
}
nvdev = hv_get_drvdata(dev);
ret = netif_set_real_num_tx_queues(net, nvdev->num_chn);
if (ret) {
if (recovering) {
netdev_err(net, "could not set tx queue count (ret %d)\n", ret);
return ret;
}
goto recover;
}
ret = netif_set_real_num_rx_queues(net, nvdev->num_chn);
if (ret) {
if (recovering) {
netdev_err(net, "could not set rx queue count (ret %d)\n", ret);
return ret;
}
goto recover;
}
out:
netvsc_open(net);
return ret;
recover:
/* If the above failed, we attempt to recover through the same
* process but with the original number of channels.
*/
netdev_err(net, "could not set channels, recovering\n");
recovering = true;
channels->combined_count = num_chn;
goto do_set;
}
static int netvsc_change_mtu(struct net_device *ndev, int mtu)
{
struct net_device_context *ndevctx = netdev_priv(ndev);
@ -802,6 +897,7 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
memset(&device_info, 0, sizeof(device_info));
device_info.ring_size = ring_size;
device_info.num_chn = nvdev->num_chn;
device_info.max_num_vrss_chns = max_num_vrss_chns;
rndis_filter_device_add(hdev, &device_info);
@ -891,6 +987,7 @@ static const struct ethtool_ops ethtool_ops = {
.get_drvinfo = netvsc_get_drvinfo,
.get_link = ethtool_op_get_link,
.get_channels = netvsc_get_channels,
.set_channels = netvsc_set_channels,
};
static const struct net_device_ops device_ops = {