Re: [PATCH net-next 1/6] bonding: verify if bond has ip only once on arp validate

[Jay Vosburgh <fubar@us.ibm.com>]

Veaceslav Falico <vfalico@redhat.com> wrote:

>It's extra work to verify bond's ip presence for every slave, so take it
>out of the loop.

	The current code doesn't verify for every slave (target address,
actually).  The call to bond_has_this_ip() happens at most once, if the
sip (source IP) matches the arp_ip_target being inspected, after which
the function returns.

	I can see that the patch will bypass the loop entirely if the
bond lacks the IP, but I'm not sure that's a meaningful improvement,
since it changes from calling bond_has_this_ip 0 or 1 times to always 1
time.

	-J


>Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
>---
> drivers/net/bonding/bond_main.c |   13 ++++++++-----
> 1 files changed, 8 insertions(+), 5 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>index bc1246f..3d8b5ba 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -2602,13 +2602,16 @@ static void bond_validate_arp(struct bonding *bond, struct slave *slave, __be32
> 	int i;
> 	__be32 *targets = bond->params.arp_targets;
>
>+	if (!bond_has_this_ip(bond, tip)) {
>+		pr_debug("bva: tip %pI4 not found\n", &tip);
>+		return;
>+	}
>+
> 	for (i = 0; (i < BOND_MAX_ARP_TARGETS) && targets[i]; i++) {
>-		pr_debug("bva: sip %pI4 tip %pI4 t[%d] %pI4 bhti(tip) %d\n",
>-			 &sip, &tip, i, &targets[i],
>-			 bond_has_this_ip(bond, tip));
>+		pr_debug("bva: sip %pI4 tip %pI4 t[%d] %pI4 bhti(tip)\n",
>+			 &sip, &tip, i, &targets[i]);
> 		if (sip == targets[i]) {
>-			if (bond_has_this_ip(bond, tip))
>-				slave->last_arp_rx = jiffies;
>+			slave->last_arp_rx = jiffies;
> 			return;
> 		}
> 	}
>-- 
>1.7.1
>

---
	-Jay Vosburgh, IBM Linux Technology Center, fubar@us.ibm.com