[PATCH 17/17] hyper-v: trace channel events

[kys at exchange.microsoft.com]

From: Vitaly Kuznetsov <vkuznets at redhat.com>

Added an additional set of trace points for when channel gets notified
or signals host.

Suggested-by: Stephen Hemminger <sthemmin at microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets at redhat.com>
Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
---
 drivers/hv/channel.c    |  2 ++
 drivers/hv/connection.c |  2 ++
 drivers/hv/hv_trace.h   | 23 +++++++++++++++++++++++
 drivers/hv/vmbus_drv.c  |  2 ++
 4 files changed, 29 insertions(+)

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index ed3634e53e15..19f0cf37e0ed 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -43,6 +43,8 @@ void vmbus_setevent(struct vmbus_channel *channel)
 {
 	struct hv_monitor_page *monitorpage;
 
+	trace_vmbus_setevent(channel);
+
 	/*
 	 * For channels marked as in "low latency" mode
 	 * bypass the monitor page mechanism.
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 05f413c4fe3b..447371f4de56 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -322,6 +322,8 @@ void vmbus_on_event(unsigned long data)
 	struct vmbus_channel *channel = (void *) data;
 	unsigned long time_limit = jiffies + 2;
 
+	trace_vmbus_on_event(channel);
+
 	do {
 		void (*callback_fn)(void *);
 
diff --git a/drivers/hv/hv_trace.h b/drivers/hv/hv_trace.h
index 5382d9630306..d635ee95b20d 100644
--- a/drivers/hv/hv_trace.h
+++ b/drivers/hv/hv_trace.h
@@ -294,6 +294,29 @@ TRACE_EVENT(vmbus_send_tl_connect_request,
 		    )
 	);
 
+DECLARE_EVENT_CLASS(vmbus_channel,
+	TP_PROTO(const struct vmbus_channel *channel),
+	TP_ARGS(channel),
+	TP_STRUCT__entry(__field(u32, relid)),
+	TP_fast_assign(__entry->relid = channel->offermsg.child_relid),
+	TP_printk("relid 0x%x", __entry->relid)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_chan_sched,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_setevent,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_on_event,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
 #undef TRACE_INCLUDE_PATH
 #define TRACE_INCLUDE_PATH .
 #undef TRACE_INCLUDE_FILE
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 8f9293a87c6b..6a86746d4f60 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -946,6 +946,8 @@ static void vmbus_chan_sched(struct hv_per_cpu_context *hv_cpu)
 			if (channel->rescind)
 				continue;
 
+			trace_vmbus_chan_sched(channel);
+
 			++channel->interrupts;
 
 			switch (channel->callback_mode) {
-- 
2.14.1