Drivers: hv: vmbus: Expose per-channel interrupts and events counters

When investigating performance, it is useful to be able to look at
the number of host and guest events per-channel. This is equivalent
to per-device interrupt statistics.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/hyperv.h

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index ea6b558..f3e97c5 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -719,6 +719,10 @@ struct vmbus_channel {
 
 	struct vmbus_close_msg close_msg;
 
+	/* Statistics */
+	u64	interrupts;	/* Host to Guest interrupts */
+	u64	sig_events;	/* Guest to Host events */
+
 	/* Channel callback's invoked in softirq context */
 	struct tasklet_struct callback_event;
 	void (*onchannel_callback)(void *context);