gallium: add interface for driver queries like performance counters, etc.

The pipe query interface is reused. The list of available queries can be
obtained using pipe_screen::get_driver_query_info.

Reviewed-by: Brian Paul <[email protected]>

1 files changed, 11 insertions, 0 deletions

diff --git a/src/gallium/include/pipe/p_screen.h b/src/gallium/include/pipe/p_screen.h
index 754cfd7c2e6..c487e8ec8a4 100644
--- a/src/gallium/include/pipe/p_screen.h
+++ b/src/gallium/include/pipe/p_screen.h
@@ -206,6 +206,17 @@ struct pipe_screen {
                             struct pipe_fence_handle *fence,
                             uint64_t timeout );
 
+   /**
+    * Returns a driver-specific query.
+    *
+    * If \p info is NULL, the number of available queries is returned.
+    * Otherwise, the driver query at the specified \p index is returned
+    * in \p info. The function returns non-zero on success.
+    */
+   int (*get_driver_query_info)(struct pipe_screen *screen,
+                                unsigned index,
+                                struct pipe_driver_query_info *info);
+
 };