[PATCH 01/16] hyper-v: trace vmbus_on_msg_dpc()

Vitaly Kuznetsov
2017-09-20T17:22:15Z

Add tracing subsystem to Hyper-V VMBus module and add tracepoint
to vmbus_on_msg_dpc() which is called when we receive a message from host.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
drivers/hv/Makefile | 4 +++-
drivers/hv/hv_trace.c | 4 ++++
drivers/hv/hv_trace.h | 24 ++++++++++++++++++++++++
drivers/hv/hyperv_vmbus.h | 2 ++
drivers/hv/vmbus_drv.c | 2 ++
5 files changed, 35 insertions(+), 1 deletion(-)
create mode 100644 drivers/hv/hv_trace.c
create mode 100644 drivers/hv/hv_trace.h

diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile
index 39c9b2c08d33..ad791e00230f 100644
--- a/drivers/hv/Makefile
+++ b/drivers/hv/Makefile
@@ -2,7 +2,9 @@ obj-$(CONFIG_HYPERV) += hv_vmbus.o
obj-$(CONFIG_HYPERV_UTILS) += hv_utils.o
obj-$(CONFIG_HYPERV_BALLOON) += hv_balloon.o

+CFLAGS_hv_trace.o = -I$(src)
+
hv_vmbus-y := vmbus_drv.o \
hv.o connection.o channel.o \
- channel_mgmt.o ring_buffer.o
+ channel_mgmt.o ring_buffer.o hv_trace.o
hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_fcopy.o hv_utils_transport.o
diff --git a/drivers/hv/hv_trace.c b/drivers/hv/hv_trace.c
new file mode 100644
index 000000000000..df47acd01a81
--- /dev/null
+++ b/drivers/hv/hv_trace.c
@@ -0,0 +1,4 @@
+#include "hyperv_vmbus.h"
+
+#define CREATE_TRACE_POINTS
+#include "hv_trace.h"
diff --git a/drivers/hv/hv_trace.h b/drivers/hv/hv_trace.h
new file mode 100644
index 000000000000..9a29ef55477d
--- /dev/null
+++ b/drivers/hv/hv_trace.h
@@ -0,0 +1,24 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM hyperv
+
+#if !defined(_HV_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _HV_TRACE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(vmbus_on_msg_dpc,
+ TP_PROTO(const struct vmbus_channel_message_header *hdr),
+ TP_ARGS(hdr),
+ TP_STRUCT__entry(__field(unsigned int, msgtype)),
+ TP_fast_assign(__entry->msgtype = hdr->msgtype),
+ TP_printk("message %u received", __entry->msgtype)
+ );
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE hv_trace
+#endif /* _HV_TRACE_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 49569f8fe038..82eb082f3302 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -31,6 +31,8 @@
#include <linux/hyperv.h>
#include <linux/interrupt.h>

+#include "hv_trace.h"
+
/*
* Timeout for services such as KVP and fcopy.
*/
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index a9d49f6f6501..ced33b1982c4 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -834,6 +834,8 @@ void vmbus_on_msg_dpc(unsigned long data)

hdr = (struct vmbus_channel_message_header *)msg->u.payload;

+ trace_vmbus_on_msg_dpc(hdr);
+
if (hdr->msgtype >= CHANNELMSG_COUNT) {
WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
goto msg_handled;
--
2.13.5