Eliminate the back-to-fake-front copy by exchanging the previous back buffer
and the fake front buffer. This is a gain except when we need to preserve
the back buffer content but in that case we still typically gain by replacing
a server-side blit by a client side non-flushing blit.
Signed-off-by: Thomas Hellstrom <thellst...@vmware.com>
Reviewed-by: Michel Dänzer <michel.daen...@amd.com>
---
src/loader/loader_dri3_helper.c | 50 +++++++++++++++++++++++++----------------
1 file changed, 31 insertions(+), 19 deletions(-)
diff --git a/src/loader/loader_dri3_helper.c b/src/loader/loader_dri3_helper.c
index 67dabe0..3434af3 100644
--- a/src/loader/loader_dri3_helper.c
+++ b/src/loader/loader_dri3_helper.c
@@ -771,13 +771,6 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable
*draw,
back->image,
0, 0, back->width, back->height,
0, 0, __BLIT_FLAG_FLUSH);
- /* Update the fake front */
- if (draw->have_fake_front)
- (void) loader_dri3_blit_image(draw,
-
draw->buffers[LOADER_DRI3_FRONT_ID]->image,
- back->image,
- 0, 0, draw->width, draw->height,
- 0, 0, __BLIT_FLAG_FLUSH);
}
/* If we need to preload the new back buffer, remember the source.
@@ -787,6 +780,20 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable
*draw,
if (draw->swap_method == __DRI_ATTRIB_SWAP_COPY || force_copy)
draw->cur_blit_source = LOADER_DRI3_BACK_ID(draw->cur_back);
+ /* Exchange the back and fake front. Even though the server knows about
these
+ * buffers, it has no notion of back and fake front.
+ */
+ if (back && draw->have_fake_front) {
+ struct loader_dri3_buffer *tmp;
+
+ tmp = dri3_fake_front_buffer(draw);
+ draw->buffers[LOADER_DRI3_FRONT_ID] = back;
+ draw->buffers[LOADER_DRI3_BACK_ID(draw->cur_back)] = tmp;
+
+ if (draw->swap_method == __DRI_ATTRIB_SWAP_COPY || force_copy)
+ draw->cur_blit_source = LOADER_DRI3_FRONT_ID;
+ }
+
dri3_flush_present_events(draw);
if (back && !draw->is_pixmap) {
@@ -852,21 +859,26 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable
*draw,
remainder, 0, NULL);
ret = (int64_t) draw->send_sbc;
- /* If there's a fake front, then copy the source back buffer
- * to the fake front to keep it up to date. This needs
- * to reset the fence and make future users block until
- * the X server is done copying the bits
+ /* Schedule a server-side back-preserving blit if necessary.
+ * This happens iff all conditions below are satisfied:
+ * a) We have a fake front,
+ * b) We need to preserve the back buffer,
+ * c) We don't have local blit capabilities.
*/
- if (draw->have_fake_front && !draw->is_different_gpu) {
- dri3_fence_reset(draw->conn, draw->buffers[LOADER_DRI3_FRONT_ID]);
- dri3_copy_area(draw->conn,
- back->pixmap,
- draw->buffers[LOADER_DRI3_FRONT_ID]->pixmap,
+ if (!loader_dri3_have_image_blit(draw) && draw->cur_blit_source != -1 &&
+ draw->cur_blit_source != LOADER_DRI3_BACK_ID(draw->cur_back)) {
+ struct loader_dri3_buffer *new_back = dri3_back_buffer(draw);
+ struct loader_dri3_buffer *src = draw->buffers[draw->cur_blit_source];
+
+ dri3_fence_reset(draw->conn, new_back);
+ dri3_copy_area(draw->conn, src->pixmap,
+ new_back->pixmap,
dri3_drawable_gc(draw),
- 0, 0, 0, 0,
- draw->width, draw->height);
- dri3_fence_trigger(draw->conn, draw->buffers[LOADER_DRI3_FRONT_ID]);
+ 0, 0, 0, 0, draw->width, draw->height);
+ dri3_fence_trigger(draw->conn, new_back);
+ new_back->last_swap = src->last_swap;
}
+
xcb_flush(draw->conn);
if (draw->stamp)
++(*draw->stamp);
--
2.7.4
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
