[ofa-general] [PATCH V3 7/7] net/bonding: Delay sending of gratuitous ARP to avoid failure

[Moni Shoua <monis@voltaire.com>]

Delay sending a gratuitous_arp when LINK_STATE_LINKWATCH_PENDING bit
in dev->state field is on. This improves the chances for the arp packet to
be transmitted.

Signed-off-by: Moni Shoua <monis@voltaire.com>
---
 drivers/net/bonding/bond_main.c |   25 +++++++++++++++++++++----
 drivers/net/bonding/bonding.h   |    1 +
 2 files changed, 22 insertions(+), 4 deletions(-)

Index: net-2.6/drivers/net/bonding/bond_main.c
===================================================================
--- net-2.6.orig/drivers/net/bonding/bond_main.c	2007-07-25 15:33:25.000000000 +0300
+++ net-2.6/drivers/net/bonding/bond_main.c	2007-07-26 18:42:59.296296622 +0300
@@ -1134,8 +1134,13 @@ void bond_change_active_slave(struct bon
 		if (new_active && !bond->do_set_mac_addr)
 			memcpy(bond->dev->dev_addr,  new_active->dev->dev_addr,
 				new_active->dev->addr_len);
-
-		bond_send_gratuitous_arp(bond);
+		if (bond->curr_active_slave &&
+			test_bit(__LINK_STATE_LINKWATCH_PENDING, &bond->curr_active_slave->dev->state)){
+			dprintk("delaying gratuitous arp on %s\n",bond->curr_active_slave->dev->name);
+			bond->send_grat_arp=1;
+		}else{
+			bond_send_gratuitous_arp(bond);
+		}
 	}
 }
 
@@ -2120,6 +2125,15 @@ void bond_mii_monitor(struct net_device 
 	 * program could monitor the link itself if needed.
 	 */
 
+	if (bond->send_grat_arp) {
+		if (bond->curr_active_slave && test_bit(__LINK_STATE_LINKWATCH_PENDING, &bond->curr_active_slave->dev->state))
+			dprintk("Needs to send gratuitous arp but not yet\n",__FUNCTION__);
+		else {
+			dprintk("sending delayed gratuitous arp on ond->curr_active_slave->dev->name\n");
+			bond_send_gratuitous_arp(bond);
+			bond->send_grat_arp=0;
+		}
+	}
 	read_lock(&bond->curr_slave_lock);
 	oldcurrent = bond->curr_active_slave;
 	read_unlock(&bond->curr_slave_lock);
@@ -2513,6 +2527,7 @@ static void bond_send_gratuitous_arp(str
 	struct slave *slave = bond->curr_active_slave;
 	struct vlan_entry *vlan;
 	struct net_device *vlan_dev;
+	int i;
 
 	dprintk("bond_send_grat_arp: bond %s slave %s\n", bond->dev->name,
 				slave ? slave->dev->name : "NULL");
@@ -2520,8 +2535,9 @@ static void bond_send_gratuitous_arp(str
 		return;
 
 	if (bond->master_ip) {
-		bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
-				  bond->master_ip, 0);
+		for (i=0;i<3;i++)
+			bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
+					  bond->master_ip, 0);
 	}
 
 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
@@ -4331,6 +4347,7 @@ static int bond_init(struct net_device *
 	bond->current_arp_slave = NULL;
 	bond->primary_slave = NULL;
 	bond->dev = bond_dev;
+	bond->send_grat_arp=0;
 	INIT_LIST_HEAD(&bond->vlan_list);
 
 	/* Initialize the device entry points */
Index: net-2.6/drivers/net/bonding/bonding.h
===================================================================
--- net-2.6.orig/drivers/net/bonding/bonding.h	2007-07-25 15:20:10.000000000 +0300
+++ net-2.6/drivers/net/bonding/bonding.h	2007-07-26 18:42:43.652087660 +0300
@@ -203,6 +203,7 @@ struct bonding {
 	struct   vlan_group *vlgrp;
 	struct   packet_type arp_mon_pt;
 	s8       do_set_mac_addr;
+	int	 send_grat_arp;
 };
 
 /**