xen-netback: split event channels support for Xen backend driver
Netback and netfront only use one event channel to do TX / RX notification,
which may cause unnecessary wake-up of processing routines. This patch adds a
new feature called feature-split-event-channels to netback, enabling it to
handle TX and RX events separately.
Netback will use tx_irq to notify guest for TX completion, rx_irq for RX
notification.
If frontend doesn't support this feature, tx_irq equals to rx_irq.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 6102a6c..8a4d77e 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -57,8 +57,12 @@
u8 fe_dev_addr[6];
- /* Physical parameters of the comms window. */
- unsigned int irq;
+ /* When feature-split-event-channels = 0, tx_irq = rx_irq. */
+ unsigned int tx_irq;
+ unsigned int rx_irq;
+ /* Only used when feature-split-event-channels = 1 */
+ char tx_irq_name[IFNAMSIZ+4]; /* DEVNAME-tx */
+ char rx_irq_name[IFNAMSIZ+4]; /* DEVNAME-rx */
/* List of frontends to notify after a batch of frames sent. */
struct list_head notify_list;
@@ -113,7 +117,8 @@
unsigned int handle);
int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
- unsigned long rx_ring_ref, unsigned int evtchn);
+ unsigned long rx_ring_ref, unsigned int tx_evtchn,
+ unsigned int rx_evtchn);
void xenvif_disconnect(struct xenvif *vif);
void xenvif_get(struct xenvif *vif);
@@ -158,4 +163,6 @@
/* Returns number of ring slots required to send an skb to the frontend */
unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
+extern bool separate_tx_rx_irq;
+
#endif /* __XEN_NETBACK__COMMON_H__ */