korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 14:34:28 +08:00
Code Issues Packages Projects Releases Wiki Activity

ibmvnic: remove ndo_poll_controller

Browse Source 
As diagnosed by Song Liu, ndo_poll_controller() can
be very dangerous on loaded hosts, since the cpu
calling ndo_poll_controller() might steal all NAPI
contexts (for all RX/TX queues of the NIC). This capture
can last for unlimited amount of time, since one
cpu is generally not able to drain all the queues under load.

ibmvnic uses NAPI for TX completions, so we better let core
networking stack call the napi->poll() to avoid the capture.

ibmvnic_netpoll_controller() was completely wrong anyway,
as it was scheduling NAPI to service RX queues (instead of TX),
so I doubt netpoll ever worked on this driver.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2018-09-27 09:32:01 -07:00 committed by David S. Miller
parent a4f570be65
commit 0c3b9d1b37
1 changed files with 0 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/net/ethernet/ibm/ibmvnic.c
View File

@ -2207,19 +2207,6 @@ restart_poll:
return frames_processed;
}
#ifdef CONFIG_NET_POLL_CONTROLLER
static void ibmvnic_netpoll_controller(struct net_device *dev)
{
struct ibmvnic_adapter *adapter = netdev_priv(dev);
int i;
replenish_pools(netdev_priv(dev));
for (i = 0; i < adapter->req_rx_queues; i++)
ibmvnic_interrupt_rx(adapter->rx_scrq[i]->irq,
adapter->rx_scrq[i]);
}
#endif
static int wait_for_reset(struct ibmvnic_adapter *adapter)
{
int rc, ret;
@ -2292,9 +2279,6 @@ static const struct net_device_ops ibmvnic_netdev_ops = {
.ndo_set_mac_address = ibmvnic_set_mac,
.ndo_validate_addr = eth_validate_addr,
.ndo_tx_timeout = ibmvnic_tx_timeout,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = ibmvnic_netpoll_controller,
#endif
.ndo_change_mtu = ibmvnic_change_mtu,
.ndo_features_check = ibmvnic_features_check,
};