drm/msm/rd: allow adding addition msg to top of dump

For faults or hangs, it is nice to be able to include a bit more
information.
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/msm_drv.h

@@ -299,7 +299,8 @@ void msm_framebuffer_describe(struct drm_framebuffer *fb, struct seq_file *m);
 int msm_debugfs_late_init(struct drm_device *dev);
 int msm_rd_debugfs_init(struct drm_minor *minor);
 void msm_rd_debugfs_cleanup(struct msm_drm_private *priv);
-void msm_rd_dump_submit(struct msm_rd_state *rd, struct msm_gem_submit *submit);
+void msm_rd_dump_submit(struct msm_rd_state *rd, struct msm_gem_submit *submit,
+		const char *fmt, ...);
 int msm_perf_debugfs_init(struct drm_minor *minor);
 void msm_perf_debugfs_cleanup(struct msm_drm_private *priv);
 #else

drivers/gpu/drm/msm/msm_gpu.c

@@ -557,7 +557,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit,
 
 	list_add_tail(&submit->node, &ring->submits);
 
-	msm_rd_dump_submit(priv->rd, submit);
+	msm_rd_dump_submit(priv->rd, submit, NULL);
 
 	update_sw_cntrs(gpu);
 

drivers/gpu/drm/msm/msm_rd.c

@@ -338,11 +338,12 @@ static void snapshot_buf(struct msm_rd_state *rd,
 }
 
 /* called under struct_mutex */
-void msm_rd_dump_submit(struct msm_rd_state *rd, struct msm_gem_submit *submit)
+void msm_rd_dump_submit(struct msm_rd_state *rd, struct msm_gem_submit *submit,
+		const char *fmt, ...)
 {
 	struct drm_device *dev = submit->dev;
 	struct task_struct *task;
-	char msg[128];
+	char msg[256];
 	int i, n;
 
 	if (!rd->open)
@@ -353,6 +354,16 @@ void msm_rd_dump_submit(struct msm_rd_state *rd, struct msm_gem_submit *submit)
 	 */
 	WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 
+	if (fmt) {
+		va_list args;
+
+		va_start(args, fmt);
+		n = vsnprintf(msg, sizeof(msg), fmt, args);
+		va_end(args);
+
+		rd_write_section(rd, RD_CMD, msg, ALIGN(n, 4));
+	}
+
 	rcu_read_lock();
 	task = pid_task(submit->pid, PIDTYPE_PID);
 	if (task) {