From: Eric Anholt <eric@anholt.net>
Date: Mon, 11 May 2020 20:46:33 +0000 (-0700)
Subject: freedreno: Add an early out for preparing to read a resource.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=d393837332a07f53b9622ca55149e63947e0f937;p=mesa.git

freedreno: Add an early out for preparing to read a resource.

nohw drawoverhead 8 UBOs test throughput 1.06093% +/- 0.363376% (n=10).

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4996>
---

diff --git a/src/gallium/drivers/freedreno/freedreno_batch.c b/src/gallium/drivers/freedreno/freedreno_batch.c
index a653e0d91a8..3ee150fce75 100644
--- a/src/gallium/drivers/freedreno/freedreno_batch.c
+++ b/src/gallium/drivers/freedreno/freedreno_batch.c
@@ -460,6 +460,13 @@ fd_batch_resource_read(struct fd_batch *batch, struct fd_resource *rsc)
 {
 	fd_screen_assert_locked(batch->ctx->screen);
 
+	/* Early out, if we hit this then we know we don't have anyone else
+	 * writing to it (since both _write and _read flush other writers), and
+	 * that we've already recursed for stencil.
+	 */
+	if (likely(fd_batch_references_resource(batch, rsc)))
+		return;
+
 	if (rsc->stencil)
 		fd_batch_resource_read(batch, rsc->stencil);