[Mesa-dev] [PATCH v4 2/3] mesa/glthread: add tracking of PBO binding

[Gregory Hainaut]

In gl core, buffer must be reserved first by CreateBuffers/GenBuffers
to be valid.

v4: update comments based on Nicolai review
Signed-off-by: Gregory Hainaut <gregory.hainaut at gmail.com>
---
 src/mesa/main/marshal.c | 36 +++++++++++++++++++++++++++++++++---
 1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/src/mesa/main/marshal.c b/src/mesa/main/marshal.c
index 4037b79..1167271 100644
--- a/src/mesa/main/marshal.c
+++ b/src/mesa/main/marshal.c
@@ -319,7 +319,20 @@ struct marshal_cmd_BindBufferBase
    GLuint buffer;
 };
 
-/** Tracks the current bindings for the vertex array and index array buffers.
+/**
+ * Check that buffer is a valid buffer handle
+ * Always return false for ID 0.
+ */
+static bool
+is_bufferobj(struct gl_context *ctx, GLuint buffer)
+{
+   if (buffer == 0)
+      return false;
+   else
+      return _mesa_HashLookup(ctx->Shared->ShadowBufferObjects, buffer) != NULL;
+}
+
+/** Tracks the current bindings of GL buffer targets
  *
  * This is part of what we need to enable glthread on compat-GL contexts that
  * happen to use VBOs, without also supporting the full tracking of VBO vs
@@ -341,9 +354,14 @@ struct marshal_cmd_BindBufferBase
  * instead of updating the binding.  However, compat GL has the ridiculous
  * feature that if you pass a bad name, it just gens a buffer object for you,
  * so we escape without having to know if things are valid or not.
+ *
+ * Pixel buffers are tracked to decide whether pixel transfer goes to a user
+ * pointer (must be synchronous) or a GL buffer (can be asynchronous). Unlike
+ * for VBOs, we do need accurate tracking, since user pointers can be used in
+ * GL core contexts.
  */
 static void
-track_vbo_binding(struct gl_context *ctx, GLenum target, GLuint buffer)
+track_buffers_binding(struct gl_context *ctx, GLenum target, GLuint buffer)
 {
    struct glthread_state *glthread = ctx->GLThread;
 
@@ -358,6 +376,18 @@ track_vbo_binding(struct gl_context *ctx, GLenum target, GLuint buffer)
        */
       glthread->element_array_is_vbo = (buffer != 0);
       break;
+   case GL_PIXEL_UNPACK_BUFFER:
+      if (ctx->API == API_OPENGL_COMPAT || is_bufferobj(ctx, buffer))
+         glthread->pixel_unpack_buffer_bound = buffer;
+      else
+         glthread->pixel_unpack_buffer_bound = 0;
+      break;
+   case GL_PIXEL_PACK_BUFFER:
+      if (ctx->API == API_OPENGL_COMPAT || is_bufferobj(ctx, buffer))
+         glthread->pixel_pack_buffer_bound = buffer;
+      else
+         glthread->pixel_pack_buffer_bound = 0;
+      break;
    }
 }
 
@@ -389,7 +419,7 @@ _mesa_marshal_BindBuffer(GLenum target, GLuint buffer)
    struct marshal_cmd_BindBuffer *cmd;
    debug_print_marshal("BindBuffer");
 
-   track_vbo_binding(ctx, target, buffer);
+   track_buffers_binding(ctx, target, buffer);
 
    if (cmd_size <= MARSHAL_MAX_CMD_SIZE) {
       cmd = _mesa_glthread_allocate_command(ctx, DISPATCH_CMD_BindBuffer,
-- 
2.1.4