From 7893b2491a2d5f716540ac5643d78d37a7f6628b Mon Sep 17 00:00:00 2001 From: Moni Shoua Date: Sat, 17 May 2008 21:10:12 -0700 Subject: bonding: Send more than one gratuitous ARP when slave takes over With IPoIB, reception of gratuitous ARP by neighboring hosts is essential for a successful change of slaves in case of failure. Otherwise, they won't learn about the HW address change and need to wait a long time until the neighboring system gives up and sends an ARP request to learn the new HW address. This patch decreases the chance for a lost of a gratuitous ARP packet by sending it more than once. The number retries is configurable and can be set with a module param. Signed-off-by: Moni Shoua Acked-by: Jay Vosburgh Signed-off-by: Jeff Garzik --- drivers/net/bonding/bond_sysfs.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) (limited to 'drivers/net/bonding/bond_sysfs.c') diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 1f02857..7a61e9a 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -951,6 +951,45 @@ out: static DEVICE_ATTR(lacp_rate, S_IRUGO | S_IWUSR, bonding_show_lacp, bonding_store_lacp); /* + * Show and set the number of grat ARP to send after a failover event. + */ +static ssize_t bonding_show_n_grat_arp(struct device *d, + struct device_attribute *attr, + char *buf) +{ + struct bonding *bond = to_bond(d); + + return sprintf(buf, "%d\n", bond->params.num_grat_arp); +} + +static ssize_t bonding_store_n_grat_arp(struct device *d, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int new_value, ret = count; + struct bonding *bond = to_bond(d); + + if (sscanf(buf, "%d", &new_value) != 1) { + printk(KERN_ERR DRV_NAME + ": %s: no num_grat_arp value specified.\n", + bond->dev->name); + ret = -EINVAL; + goto out; + } + if (new_value < 0 || new_value > 255) { + printk(KERN_ERR DRV_NAME + ": %s: Invalid num_grat_arp value %d not in range 0-255; rejected.\n", + bond->dev->name, new_value); + ret = -EINVAL; + goto out; + } else { + bond->params.num_grat_arp = new_value; + } +out: + return ret; +} +static DEVICE_ATTR(num_grat_arp, S_IRUGO | S_IWUSR, bonding_show_n_grat_arp, bonding_store_n_grat_arp); +/* * Show and set the MII monitor interval. There are two tricky bits * here. First, if MII monitoring is activated, then we must disable * ARP monitoring. Second, if the timer isn't running, we must @@ -1387,6 +1426,7 @@ static struct attribute *per_bond_attrs[] = { &dev_attr_updelay.attr, &dev_attr_lacp_rate.attr, &dev_attr_xmit_hash_policy.attr, + &dev_attr_num_grat_arp.attr, &dev_attr_miimon.attr, &dev_attr_primary.attr, &dev_attr_use_carrier.attr, -- cgit v1.1