Mesa (master): radv: only emit cache flushes when the pool size is large enough

[Samuel Pitoiset]

Module: Mesa
Branch: master
Commit: c27f5419f6f6aa6d51b44a99b6738fba70873604
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=c27f5419f6f6aa6d51b44a99b6738fba70873604

Author: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Date:   Wed Feb 28 20:28:53 2018 +0100

radv: only emit cache flushes when the pool size is large enough

This is an optimization which reduces the number of flushes for
small pool buffers.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas at basnieuwenhuizen.nl>

---

 src/amd/vulkan/radv_meta_buffer.c |  6 ------
 src/amd/vulkan/radv_private.h     |  6 ++++++
 src/amd/vulkan/radv_query.c       | 14 +++++++++-----
 3 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/src/amd/vulkan/radv_meta_buffer.c b/src/amd/vulkan/radv_meta_buffer.c
index e6ad235e93..2e1ba2c7b2 100644
--- a/src/amd/vulkan/radv_meta_buffer.c
+++ b/src/amd/vulkan/radv_meta_buffer.c
@@ -4,12 +4,6 @@
 #include "sid.h"
 #include "radv_cs.h"
 
-/*
- * This is the point we switch from using CP to compute shader
- * for certain buffer operations.
- */
-#define RADV_BUFFER_OPS_CS_THRESHOLD 4096
-
 static nir_shader *
 build_buffer_fill_shader(struct radv_device *dev)
 {
diff --git a/src/amd/vulkan/radv_private.h b/src/amd/vulkan/radv_private.h
index 752b6a7592..0f8ddb2e10 100644
--- a/src/amd/vulkan/radv_private.h
+++ b/src/amd/vulkan/radv_private.h
@@ -95,6 +95,12 @@ typedef uint32_t xcb_window_t;
 
 #define NUM_DEPTH_CLEAR_PIPELINES 3
 
+/*
+ * This is the point we switch from using CP to compute shader
+ * for certain buffer operations.
+ */
+#define RADV_BUFFER_OPS_CS_THRESHOLD 4096
+
 enum radv_mem_heap {
 	RADV_MEM_HEAP_VRAM,
 	RADV_MEM_HEAP_VRAM_CPU_ACCESS,
diff --git a/src/amd/vulkan/radv_query.c b/src/amd/vulkan/radv_query.c
index ff2782bae8..9fee4d2b49 100644
--- a/src/amd/vulkan/radv_query.c
+++ b/src/amd/vulkan/radv_query.c
@@ -1092,11 +1092,15 @@ void radv_CmdBeginQuery(
 	radv_cs_add_buffer(cmd_buffer->device->ws, cs, pool->bo, 8);
 
 	if (cmd_buffer->pending_reset_query) {
-		/* Make sure to flush caches if the query pool has been
-		 * previously resetted using the compute shader path.
-		 */
-		si_emit_cache_flush(cmd_buffer);
-		cmd_buffer->pending_reset_query = false;
+		if (pool->size >= RADV_BUFFER_OPS_CS_THRESHOLD) {
+			/* Only need to flush caches if the query pool size is
+			 * large enough to be resetted using the compute shader
+			 * path. Small pools don't need any cache flushes
+			 * because we use a CP dma clear.
+			 */
+			si_emit_cache_flush(cmd_buffer);
+			cmd_buffer->pending_reset_query = false;
+		}
 	}
 
 	switch (pool->type) {