+typedef enum
+{
+ METRICS_OP_ACCUM,
+ METRICS_OP_BUFFER_DATA,
+ METRICS_OP_BUFFER_SUB_DATA,
+ METRICS_OP_BITMAP,
+ METRICS_OP_BLIT_FRAMEBUFFER,
+ METRICS_OP_CLEAR,
+ METRICS_OP_CLEAR_BUFFER_DATA,
+ METRICS_OP_CLEAR_TEX_IMAGE,
+ METRICS_OP_COPY_PIXELS,
+ METRICS_OP_COPY_TEX_IMAGE,
+ METRICS_OP_DRAW_PIXELS,
+ METRICS_OP_GET_TEX_IMAGE,
+ METRICS_OP_READ_PIXELS,
+ METRICS_OP_TEX_IMAGE,
+
+ /* METRICS_OP_SHADER must be last.
+ *
+ * All larger values for metrics_op_t are interpreted as:
+ *
+ * METRICS_OP_SHADER + shader_program_number
+ *
+ * to indicate a specific shader program.
+ */
+ METRICS_OP_SHADER
+} metrics_op_t;
+
+/* Timer query */
+typedef struct timer_query
+{
+ unsigned id;
+
+ metrics_op_t op;
+ struct timer_query *next;
+} timer_query_t;
+
+/* Performance-monitor query */
+typedef struct monitor
+{
+ unsigned id;
+
+ metrics_op_t op;
+ struct monitor *next;
+} monitor_t;
+
+typedef struct op_metrics
+{
+ /* This happens to also be the index into the
+ * ctx->op_metrics array currently
+ */
+ metrics_op_t op;
+ double time_ns;
+
+ double **counters;
+} op_metrics_t;
+
+typedef struct metrics
+{
+ metrics_op_t op;
+
+ /* GL_TIME_ELAPSED query for which glEndQuery has not yet
+ * been called. */
+ unsigned timer_begun_id;
+
+ /* GL_TIME_ELAPSED queries for which glEndQuery has been
+ * called, (but results have not yet been queried). */
+ timer_query_t *timer_head;
+ timer_query_t *timer_tail;
+
+ /* Performance monitor for which glEndPerfMonitorAMD has not
+ * yet been called. */
+ unsigned monitor_begun_id;
+
+ /* Performance monitors for which glEndPerfMonitorAMD has
+ * been called, (but results have not yet been queried). */
+ monitor_t *monitor_head;
+ monitor_t *monitor_tail;
+
+ int monitors_in_flight;
+
+ unsigned num_op_metrics;
+ op_metrics_t *op_metrics;
+} metrics_t;
+
+/* Initialize a metrics_t object for tracking metrics. */
+void
+metrics_init (metrics_t *metrics);
+
+/* Cleanup a metrics_t object that's no longer needed. */
+void
+metrics_fini (metrics_t *metrics);
+
+/* Start accumulating GPU time.