Re: [ofa-general] [PATCH] RDMA/CMA: Use neigh_event_send() to initiateneighbour discovery.

From: Or Gerlitz
Date: Sun Sep 16 2007 - 03:51:32 EST


Steve Wise wrote:
RDMA/CMA: Use neigh_event_send() to initiate neighbour discovery.

Calling arp_send() to initiate neighbour discovery (ND) doesn't do the
full ND protocol. Namely, it doesn't handle retransmitting the arp
request if it is dropped. The function neigh_event_send() does all this.
Without doing full ND, rdma address resolution fails in the presence of
dropped arp bcast packets.

Jay,

Is there a way to deploy something similar for the gratuitous arp being sent by the bonding driver at bond_arp_send()?

We have seen rare situations where the skb was dropped by the stack and hence bonding fail-over was detected by the remote peer only when its neighboring subsystem probe failures dictated that a new arp must be issued.

Or.

Signed-off-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
---

drivers/infiniband/core/addr.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index c5c33d3..5381c80 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -161,8 +161,7 @@ static void addr_send_arp(struct sockadd
if (ip_route_output_key(&rt, &fl))
return;
- arp_send(ARPOP_REQUEST, ETH_P_ARP, rt->rt_gateway, rt->idev->dev,
- rt->rt_src, NULL, rt->idev->dev->dev_addr, NULL);
+ neigh_event_send(rt->u.dst.neighbour, NULL);
ip_rt_put(rt);
}

-
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