vhost: Add event index for interrupt notification to driver

VPP only supports a poor man's approach for interrupt notification to the
driver. It uses a simple binary flag for "interrupt needed" or "interrupt
not needed". Most drivers support more sophisticated event index already.
This feature is to add the long due missing feature and make it configurable,
off by default.

Type: feature

Signed-off-by: Steven Luong <sluong@cisco.com>
Change-Id: I68dab7dd07045cafb49af97b7f70db9b8131ae03

1 files changed, 23 insertions, 8 deletions

diff --git a/src/vnet/devices/virtio/vhost_user.h b/src/vnet/devices/virtio/vhost_user.h
index eecfd2d60e5..604e5571141 100644
--- a/src/vnet/devices/virtio/vhost_user.h
+++ b/src/vnet/devices/virtio/vhost_user.h
@@ -97,16 +97,27 @@ typedef enum
   (FEATURE_VIRTIO_NET_F_HOST_TSO_FEATURE_BITS |		 \
    FEATURE_VIRTIO_NET_F_GUEST_TSO_FEATURE_BITS)
 
+
+typedef struct
+{
+  char *sock_filename;
+  u64 feature_mask;
+  u32 custom_dev_instance;
+  u8 hwaddr[6];
+  u8 renumber;
+  u8 is_server;
+  u8 enable_gso;
+  u8 enable_packed;
+  u8 enable_event_idx;
+
+  /* return */
+  u32 sw_if_index;
+} vhost_user_create_if_args_t;
+
 int vhost_user_create_if (vnet_main_t * vnm, vlib_main_t * vm,
-			  const char *sock_filename, u8 is_server,
-			  u32 * sw_if_index, u64 feature_mask,
-			  u8 renumber, u32 custom_dev_instance, u8 * hwaddr,
-			  u8 enable_gso, u8 enable_packed);
+			  vhost_user_create_if_args_t * args);
 int vhost_user_modify_if (vnet_main_t * vnm, vlib_main_t * vm,
-			  const char *sock_filename, u8 is_server,
-			  u32 sw_if_index, u64 feature_mask,
-			  u8 renumber, u32 custom_dev_instance,
-			  u8 enable_gso, u8 enable_packed);
+			  vhost_user_create_if_args_t * args);
 int vhost_user_delete_if (vnet_main_t * vnm, vlib_main_t * vm,
 			  u32 sw_if_index);
 
@@ -216,6 +227,9 @@ typedef struct
 
   u16 used_wrap_counter;
   u16 avail_wrap_counter;
+
+  u16 last_kick;
+  u8 first_kick;
 } vhost_user_vring_t;
 
 #define VHOST_USER_EVENT_START_TIMER 1
@@ -272,6 +286,7 @@ typedef struct
   /* Packed ring configured */
   u8 enable_packed;
 
+  u8 enable_event_idx;
 } vhost_user_intf_t;
 
 typedef struct