drm/lima: add trace point for tasks

track lima task start which can be combined with
dma_fence_signal to identify task execution time.

example command to record:

trace-cmd record -i \
  -e "lima:lima_task_submit" -e "lima:lima_task_run" \
  -e "*fence:*fence_signaled" -e "drm:drm_vblank_event" \
  -e "drm:drm_vblank_event_queued" sleep 4

Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200307135438.9981-1-yuq825@gmail.com

drivers/gpu/drm/lima/Makefile

@@ -14,6 +14,7 @@ lima-y := \
 	lima_sched.o \
 	lima_ctx.o \
 	lima_dlbu.o \
-	lima_bcast.o
+	lima_bcast.o \
+	lima_trace.o
 
 obj-$(CONFIG_DRM_LIMA) += lima.o

drivers/gpu/drm/lima/lima_sched.c

@@ -3,7 +3,6 @@
 
 #include <linux/kthread.h>
 #include <linux/slab.h>
-#include <linux/xarray.h>
 #include <linux/vmalloc.h>
 
 #include "lima_drv.h"
@@ -12,6 +11,7 @@
 #include "lima_mmu.h"
 #include "lima_l2_cache.h"
 #include "lima_gem.h"
+#include "lima_trace.h"
 
 struct lima_fence {
 	struct dma_fence base;
@@ -177,6 +177,7 @@ struct dma_fence *lima_sched_context_queue_task(struct lima_sched_context *conte
 {
 	struct dma_fence *fence = dma_fence_get(&task->base.s_fence->finished);
 
+	trace_lima_task_submit(task);
 	drm_sched_entity_push_job(&task->base, &context->base);
 	return fence;
 }
@@ -251,6 +252,8 @@ static struct dma_fence *lima_sched_run_job(struct drm_sched_job *job)
 	if (last_vm)
 		lima_vm_put(last_vm);
 
+	trace_lima_task_run(task);
+
 	pipe->error = false;
 	pipe->task_run(pipe, task);
 

drivers/gpu/drm/lima/lima_sched.h

@@ -6,6 +6,7 @@
 
 #include <drm/gpu_scheduler.h>
 #include <linux/list.h>
+#include <linux/xarray.h>
 
 struct lima_vm;
 

drivers/gpu/drm/lima/lima_trace.c

+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/* Copyright 2020 Qiang Yu <yuq825@gmail.com> */
+
+#include "lima_sched.h"
+
+#define CREATE_TRACE_POINTS
+#include "lima_trace.h"

drivers/gpu/drm/lima/lima_trace.h

+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/* Copyright 2020 Qiang Yu <yuq825@gmail.com> */
+
+#if !defined(_LIMA_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _LIMA_TRACE_H_
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM lima
+#define TRACE_INCLUDE_FILE lima_trace
+
+DECLARE_EVENT_CLASS(lima_task,
+	TP_PROTO(struct lima_sched_task *task),
+	TP_ARGS(task),
+	TP_STRUCT__entry(
+		__field(uint64_t, task_id)
+		__field(unsigned int, context)
+		__field(unsigned int, seqno)
+		__string(pipe, task->base.sched->name)
+		),
+
+	TP_fast_assign(
+		__entry->task_id = task->base.id;
+		__entry->context = task->base.s_fence->finished.context;
+		__entry->seqno = task->base.s_fence->finished.seqno;
+		__assign_str(pipe, task->base.sched->name)
+		),
+
+	TP_printk("task=%llu, context=%u seqno=%u pipe=%s",
+		  __entry->task_id, __entry->context, __entry->seqno,
+		  __get_str(pipe))
+);
+
+DEFINE_EVENT(lima_task, lima_task_submit,
+	     TP_PROTO(struct lima_sched_task *task),
+	     TP_ARGS(task)
+);
+
+DEFINE_EVENT(lima_task, lima_task_run,
+	     TP_PROTO(struct lima_sched_task *task),
+	     TP_ARGS(task)
+);
+
+#endif
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../drivers/gpu/drm/lima
+#include <trace/define_trace.h>