Re: [PATCH 02/12 -Rev2] Changes to netdevice.h

Re: [PATCH 02/12 -Rev2] Changes to netdevice.h

[Krishna Kumar2]

Hi Patrick,

Krishna Kumar2/India/IBM wrote on 07/23/2007 08:27:53 AM:

> Hi Patrick,
>
> Patrick McHardy <kaber@trash.net> wrote on 07/22/2007 10:36:51 PM:
>
> > Krishna Kumar wrote:
> > > @@ -472,6 +474,9 @@ struct net_device
> > >     void         *priv;   /* pointer to private data   */
> > >     int         (*hard_start_xmit) (struct sk_buff *skb,
> > >                        struct net_device *dev);
> > > +   int         (*hard_start_xmit_batch) (struct net_device
> > > +                       *dev);
> > > +
> >
> >
> > Os this function really needed? Can't you just call hard_start_xmit
with
> > a NULL skb and have the driver use dev->blist?

> Probably not. I will see how to do it this way and get back to you.

I think this is a good idea and makes code everywhere simpler. I
will try this change and test to make sure it doesn't have any
negative impact. Will mostly send out rev3 tomorrow.

Thanks,

- KK

[PATCH 02/12 -Rev2] Changes to netdevice.h

[Krishna Kumar]

diff -ruNp org/include/linux/netdevice.h rev2/include/linux/netdevice.h
--- org/include/linux/netdevice.h	2007-07-20 07:49:28.000000000 +0530
+++ rev2/include/linux/netdevice.h	2007-07-22 13:20:16.000000000 +0530
@@ -340,6 +340,7 @@ struct net_device
 #define NETIF_F_VLAN_CHALLENGED	1024	/* Device cannot handle VLAN packets */
 #define NETIF_F_GSO		2048	/* Enable software GSO. */
 #define NETIF_F_LLTX		4096	/* LockLess TX */
+#define NETIF_F_BATCH_ON	8192	/* Batching skbs xmit API is enabled */
 #define NETIF_F_MULTI_QUEUE	16384	/* Has multiple TX/RX queues */
 
 	/* Segmentation offload features */
@@ -452,6 +453,7 @@ struct net_device
 	struct Qdisc		*qdisc_sleeping;
 	struct list_head	qdisc_list;
 	unsigned long		tx_queue_len;	/* Max frames per queue allowed */
+	struct sk_buff_head	skb_blist;	/* List of batch skbs */
 
 	/* Partially transmitted GSO packet. */
 	struct sk_buff		*gso_skb;
@@ -472,6 +474,9 @@ struct net_device
 	void			*priv;	/* pointer to private data	*/
 	int			(*hard_start_xmit) (struct sk_buff *skb,
 						    struct net_device *dev);
+	int			(*hard_start_xmit_batch) (struct net_device
+							  *dev);
+
 	/* These may be needed for future network-power-down code. */
 	unsigned long		trans_start;	/* Time (in jiffies) of last Tx	*/
 
@@ -582,6 +587,8 @@ struct net_device
 #define	NETDEV_ALIGN		32
 #define	NETDEV_ALIGN_CONST	(NETDEV_ALIGN - 1)
 
+#define BATCHING_ON(dev)	((dev->features & NETIF_F_BATCH_ON) != 0)
+
 static inline void *netdev_priv(const struct net_device *dev)
 {
 	return dev->priv;
@@ -832,6 +839,8 @@ extern int		dev_set_mac_address(struct n
 					    struct sockaddr *);
 extern int		dev_hard_start_xmit(struct sk_buff *skb,
 					    struct net_device *dev);
+extern int		dev_add_skb_to_blist(struct sk_buff *skb,
+					     struct net_device *dev);
 
 extern void		dev_init(void);
 
@@ -1104,6 +1113,8 @@ extern void		dev_set_promiscuity(struct 
 extern void		dev_set_allmulti(struct net_device *dev, int inc);
 extern void		netdev_state_change(struct net_device *dev);
 extern void		netdev_features_change(struct net_device *dev);
+extern int		dev_change_tx_batching(struct net_device *dev,
+					       unsigned long new_batch_skb);
 /* Load a device via the kmod */
 extern void		dev_load(const char *name);
 extern void		dev_mcast_init(void);