[Mesa-dev] [PATCH 24/27] i965/miptree: Drop MIPTREE_LAYOUT_ACCELERATED_UPLOAD in mcs init

Topi Pohjolainen topi.pohjolainen at gmail.com
Mon Jan 16 09:13:59 UTC 2017


because buffers get unconditionally initialised by cpu writing.

Signed-off-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
---
 src/mesa/drivers/dri/i965/intel_mipmap_tree.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index 9462e98..20b57d1 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -1519,7 +1519,12 @@ intel_miptree_alloc_mcs(struct brw_context *brw,
    assert(temp_mcs_surf.size &&
           (temp_mcs_surf.size % temp_mcs_surf.row_pitch == 0));
 
-   const uint32_t alloc_flags = BO_ALLOC_FOR_RENDER;
+   /* Buffer needs to be initialised requiring the buffer to be immediately
+    * mapped to cpu space for writing. Therefore do not use the gpu access
+    * flag which can cause an unnecessary delay if the backing pages happened
+    * to be just used by the GPU.
+    */
+   const uint32_t alloc_flags = 0;
    mt->mcs_buf = intel_alloc_aux_buffer(brw, "mcs-miptree",
                                         &temp_main_surf, &temp_mcs_surf,
                                         alloc_flags, mt);
-- 
2.5.5



More information about the mesa-dev mailing list