drm/virtio: add trace events for commands

Trace when commands are queued for both ctrlq and cursorq.  Trace
when responses are received for ctrlq.
Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190429220825.156644-3-olvaffe@gmail.comSigned-off-by: Gerd Hoffmann <kraxel@redhat.com>

drivers/gpu/drm/virtio/Makefile

@@ -6,6 +6,6 @@
 virtio-gpu-y := virtgpu_drv.o virtgpu_kms.o virtgpu_gem.o \
 	virtgpu_fb.o virtgpu_display.o virtgpu_vq.o virtgpu_ttm.o \
 	virtgpu_fence.o virtgpu_object.o virtgpu_debugfs.o virtgpu_plane.o \
-	virtgpu_ioctl.o virtgpu_prime.o
+	virtgpu_ioctl.o virtgpu_prime.o virtgpu_trace_points.o
 
 obj-$(CONFIG_DRM_VIRTIO_GPU) += virtio-gpu.o

drivers/gpu/drm/virtio/virtgpu_trace.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#if !defined(_VIRTGPU_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
+#define _VIRTGPU_TRACE_H_
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM virtio_gpu
+#define TRACE_INCLUDE_FILE virtgpu_trace
+
+DECLARE_EVENT_CLASS(virtio_gpu_cmd,
+	TP_PROTO(struct virtqueue *vq, struct virtio_gpu_ctrl_hdr *hdr),
+	TP_ARGS(vq, hdr),
+	TP_STRUCT__entry(
+			 __field(int, dev)
+			 __field(unsigned int, vq)
+			 __field(const char *, name)
+			 __field(u32, type)
+			 __field(u32, flags)
+			 __field(u64, fence_id)
+			 __field(u32, ctx_id)
+			 ),
+	TP_fast_assign(
+		       __entry->dev = vq->vdev->index;
+		       __entry->vq = vq->index;
+		       __entry->name = vq->name;
+		       __entry->type = le32_to_cpu(hdr->type);
+		       __entry->flags = le32_to_cpu(hdr->flags);
+		       __entry->fence_id = le64_to_cpu(hdr->fence_id);
+		       __entry->ctx_id = le32_to_cpu(hdr->ctx_id);
+		       ),
+	TP_printk("vdev=%d vq=%u name=%s type=0x%x flags=0x%x fence_id=%llu ctx_id=%u",
+		  __entry->dev, __entry->vq, __entry->name,
+		  __entry->type, __entry->flags, __entry->fence_id,
+		  __entry->ctx_id)
+);
+
+DEFINE_EVENT(virtio_gpu_cmd, virtio_gpu_cmd_queue,
+	TP_PROTO(struct virtqueue *vq, struct virtio_gpu_ctrl_hdr *hdr),
+	TP_ARGS(vq, hdr)
+);
+
+DEFINE_EVENT(virtio_gpu_cmd, virtio_gpu_cmd_response,
+	TP_PROTO(struct virtqueue *vq, struct virtio_gpu_ctrl_hdr *hdr),
+	TP_ARGS(vq, hdr)
+);
+
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../drivers/gpu/drm/virtio
+#include <trace/define_trace.h>

drivers/gpu/drm/virtio/virtgpu_trace_points.c

+// SPDX-License-Identifier: GPL-2.0
+#include "virtgpu_drv.h"
+
+#define CREATE_TRACE_POINTS
+#include "virtgpu_trace.h"

drivers/gpu/drm/virtio/virtgpu_vq.c

@@ -28,6 +28,7 @@
 
 #include <drm/drmP.h>
 #include "virtgpu_drv.h"
+#include "virtgpu_trace.h"
 #include <linux/virtio.h>
 #include <linux/virtio_config.h>
 #include <linux/virtio_ring.h>
@@ -192,6 +193,9 @@ void virtio_gpu_dequeue_ctrl_func(struct work_struct *work)
 
 	list_for_each_entry_safe(entry, tmp, &reclaim_list, list) {
 		resp = (struct virtio_gpu_ctrl_hdr *)entry->resp_buf;
+
+		trace_virtio_gpu_cmd_response(vgdev->ctrlq.vq, resp);
+
 		if (resp->type != cpu_to_le32(VIRTIO_GPU_RESP_OK_NODATA)) {
 			if (resp->type >= cpu_to_le32(VIRTIO_GPU_RESP_ERR_UNSPEC)) {
 				struct virtio_gpu_ctrl_hdr *cmd;
@@ -284,6 +288,9 @@ static int virtio_gpu_queue_ctrl_buffer_locked(struct virtio_gpu_device *vgdev,
 		spin_lock(&vgdev->ctrlq.qlock);
 		goto retry;
 	} else {
+		trace_virtio_gpu_cmd_queue(vq,
+			(struct virtio_gpu_ctrl_hdr *)vbuf->buf);
+
 		virtqueue_kick(vq);
 	}
 
@@ -359,6 +366,9 @@ static int virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev,
 		spin_lock(&vgdev->cursorq.qlock);
 		goto retry;
 	} else {
+		trace_virtio_gpu_cmd_queue(vq,
+			(struct virtio_gpu_ctrl_hdr *)vbuf->buf);
+
 		virtqueue_kick(vq);
 	}