[PATCH v5 1/4] bonding: Changed hashing function to just provide hash

[PATCH v5 1/4] bonding: Changed hashing function to just provide hash

[Mahesh Bandewar]

Modified the hash function to return just hash separating from the
modulo operation that can be performed by the caller. This is to
make way for the tlb mode to use the same hashing policies that
are used in the 802.3ad and Xor mode.

Change-Id: I276609e87e0ca213c4d1b17b79c5e0b0f3d0dd6f
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
---
v2:
  Change the return type of bond_xmit_hash() from int to u32
v3:
  Rebase.
v4:
  Removed spurious net/sock.h inclusion
v5:
  Rebase.

 drivers/net/bonding/bond_3ad.c  |  2 +-
 drivers/net/bonding/bond_main.c | 10 ++++------
 drivers/net/bonding/bonding.h   |  2 +-
 3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index b667a51ed215..9a0d61e0c188 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2440,7 +2440,7 @@ int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev)
 		goto err_free;
 	}
 
-	slave_agg_no = bond_xmit_hash(bond, skb, slaves_in_agg);
+	slave_agg_no = bond_xmit_hash(bond, skb) % slaves_in_agg;
 	first_ok_slave = NULL;
 
 	bond_for_each_slave_rcu(bond, slave, iter) {
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 69aff72c8957..c7046350c4b5 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -3015,20 +3015,18 @@ static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb,
  * bond_xmit_hash - generate a hash value based on the xmit policy
  * @bond: bonding device
  * @skb: buffer to use for headers
- * @count: modulo value
  *
  * This function will extract the necessary headers from the skb buffer and use
  * them to generate a hash based on the xmit_policy set in the bonding device
- * which will be reduced modulo count before returning.
  */
-int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count)
+u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb)
 {
 	struct flow_keys flow;
 	u32 hash;
 
 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER2 ||
 	    !bond_flow_dissect(bond, skb, &flow))
-		return bond_eth_hash(skb) % count;
+		return bond_eth_hash(skb);
 
 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER23 ||
 	    bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP23)
@@ -3039,7 +3037,7 @@ int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count)
 	hash ^= (hash >> 16);
 	hash ^= (hash >> 8);
 
-	return hash % count;
+	return hash;
 }
 
 /*-------------------------- Device entry points ----------------------------*/
@@ -3666,7 +3664,7 @@ static int bond_xmit_xor(struct sk_buff *skb, struct net_device *bond_dev)
 {
 	struct bonding *bond = netdev_priv(bond_dev);
 
-	bond_xmit_slave_id(bond, skb, bond_xmit_hash(bond, skb, bond->slave_cnt));
+	bond_xmit_slave_id(bond, skb, bond_xmit_hash(bond, skb) % bond->slave_cnt);
 
 	return NETDEV_TX_OK;
 }
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index b8bdd0acc8f3..c0948ca26389 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -499,7 +499,7 @@ int bond_sysfs_slave_add(struct slave *slave);
 void bond_sysfs_slave_del(struct slave *slave);
 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev);
 int bond_release(struct net_device *bond_dev, struct net_device *slave_dev);
-int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count);
+u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb);
 void bond_select_active_slave(struct bonding *bond);
 void bond_change_active_slave(struct bonding *bond, struct slave *new_active);
 void bond_create_debugfs(void);
-- 
1.9.1.423.g4596e3a

Re: [PATCH v5 1/4] bonding: Changed hashing function to just provide hash

[David Miller]

From: Mahesh Bandewar <maheshb@google.com>
Date: Tue, 22 Apr 2014 16:30:15 -0700

> Modified the hash function to return just hash separating from the
> modulo operation that can be performed by the caller. This is to
> make way for the tlb mode to use the same hashing policies that
> are used in the 802.3ad and Xor mode.
> 
> Change-Id: I276609e87e0ca213c4d1b17b79c5e0b0f3d0dd6f
> Signed-off-by: Mahesh Bandewar <maheshb@google.com>

Applied.