On 2020-10-30 13:27, Jakub Kicinski wrote:
On Wed, 28 Oct 2020 00:57:41 -0500 Lijun Pan wrote:
We need to notify peers only when failover and migration happen.
It is unnecessary to call that in other events like
FATAL, NON_FATAL, CHANGE_PARAM, and TIMEOUT resets
since in those scenarios the MAC address and ip address mapping
does not change. Originally all the resets except CHANGE_PARAM
are processed by do_reset such that we need to find out
failover and migration cases in do_reset and call notifier functions.
We only need to notify peers in do_reset and do_hard_reset.
We don't need notify peers in do_change_param_reset since it is
a CHANGE_PARAM reset. In a nested reset case, it will finally
call into do_hard_reset with reasons other than failvoer and
migration. So, we don't need to check the reset reason in
do_hard_reset and just call notifier functions anyway.
You're completely undoing the commit you linked to:
Testing is underway. We will clarify the description in the next
version.
Thank you for your review and feedback.
Dany
commit 61d3e1d9bc2a1910d773cbf4ed6f587a7a6166b5
Author: Nathan Fontenot <nf...@linux.vnet.ibm.com>
Date: Mon Jun 12 20:47:45 2017 -0400
ibmvnic: Remove netdev notify for failover resets
When handling a driver reset due to a failover of the backing
server on the vios, doing the netdev_notify_peers() can cause
network traffic to stall or halt. Remove the netdev notify call
for failover resets.
Signed-off-by: Nathan Fontenot <nf...@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c
b/drivers/net/ethernet/ibm/ibmvnic.c
index fd3ef3005fb0..59ea7a5ae776 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1364,7 +1364,9 @@ static int do_reset(struct ibmvnic_adapter
*adapter,
for (i = 0; i < adapter->req_rx_queues; i++)
napi_schedule(&adapter->napi[i]);
- netdev_notify_peers(netdev);
+ if (adapter->reset_reason != VNIC_RESET_FAILOVER)
+ netdev_notify_peers(netdev);
+
return 0;
}
But you don't seem to address why this change was unnecessary.
AFAIK you're saying "we only need this event for FAILOVER and MOBILITY"
but the previous commit _excluded_ FAILOVER for some vague reason.
If the previous commit was incorrect you need to explain that in the
commit message.
netdev_notify_peers calls below two functions with rtnl lock().
call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
When netdev_notify_peers was substituted in
commit 986103e7920c ("net/ibmvnic: Fix RTNL deadlock during device
reset"),
call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev) was missed.
That should be a separate patch.
Fixes: 61d3e1d9bc2a ("ibmvnic: Remove netdev notify for failover
resets")
Fixes: 986103e7920c ("net/ibmvnic: Fix RTNL deadlock during device
reset")
Please don't line-wrap fixes tags.
Suggested-by: Brian King <brk...@linux.vnet.ibm.com>
Suggested-by: Pradeep Satyanarayana <prade...@linux.vnet.ibm.com>
Signed-off-by: Dany Madden <d...@linux.ibm.com>
Signed-off-by: Lijun Pan <l...@linux.ibm.com>
---
drivers/net/ethernet/ibm/ibmvnic.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c
b/drivers/net/ethernet/ibm/ibmvnic.c
index 1b702a43a5d0..718da39f5ae4 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -2067,8 +2067,11 @@ static int do_reset(struct ibmvnic_adapter
*adapter,
for (i = 0; i < adapter->req_rx_queues; i++)
napi_schedule(&adapter->napi[i]);
- if (adapter->reset_reason != VNIC_RESET_FAILOVER)
+ if (adapter->reset_reason == VNIC_RESET_FAILOVER ||
+ adapter->reset_reason == VNIC_RESET_MOBILITY) {
call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, netdev);
+ call_netdevice_notifiers(NETDEV_RESEND_IGMP, netdev);
+ }
rc = 0;
@@ -2138,6 +2141,9 @@ static int do_hard_reset(struct ibmvnic_adapter
*adapter,
if (rc)
return IBMVNIC_OPEN_FAILED;
+ call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, netdev);
+ call_netdevice_notifiers(NETDEV_RESEND_IGMP, netdev);
+
return 0;
}
