[Intel-gfx] [PATCH 5/6] drm/i915: Remove the explicit flush of the GPU write domain

[Chris Wilson]

Rely instead on the insertion of the implicit flush before the seqno
breadcrumb.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c |   34 ----------------------------------
 1 file changed, 34 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index e574835..b22bfc8 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -37,7 +37,6 @@
 #include <linux/pci.h>
 #include <linux/dma-buf.h>
 
-static __must_check int i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj);
 static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
 static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj);
 static __must_check int i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
@@ -2003,10 +2002,6 @@ i915_gem_object_flush_active(struct drm_i915_gem_object *obj)
 	int ret;
 
 	if (obj->active) {
-		ret = i915_gem_object_flush_gpu_write_domain(obj);
-		if (ret)
-			return ret;
-
 		ret = i915_gem_check_olr(obj->ring,
 					 obj->last_rendering_seqno);
 		if (ret)
@@ -2764,17 +2759,6 @@ i915_gem_clflush_object(struct drm_i915_gem_object *obj)
 	drm_clflush_pages(obj->pages, obj->base.size / PAGE_SIZE);
 }
 
-/** Flushes any GPU write domain for the object if it's dirty. */
-static int
-i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj)
-{
-	if ((obj->base.write_domain & I915_GEM_GPU_DOMAINS) == 0)
-		return 0;
-
-	/* Queue the GPU write cache flushing we need. */
-	return i915_gem_flush_ring(obj->ring, 0, obj->base.write_domain);
-}
-
 /** Flushes the GTT write domain for the object if it's dirty. */
 static void
 i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj)
@@ -2841,10 +2825,6 @@ i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write)
 	if (obj->base.write_domain == I915_GEM_DOMAIN_GTT)
 		return 0;
 
-	ret = i915_gem_object_flush_gpu_write_domain(obj);
-	if (ret)
-		return ret;
-
 	if (obj->pending_gpu_write || write) {
 		ret = i915_gem_object_wait_rendering(obj);
 		if (ret)
@@ -2957,10 +2937,6 @@ i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
 	u32 old_read_domains, old_write_domain;
 	int ret;
 
-	ret = i915_gem_object_flush_gpu_write_domain(obj);
-	if (ret)
-		return ret;
-
 	if (pipelined != obj->ring) {
 		ret = i915_gem_object_sync(obj, pipelined);
 		if (ret)
@@ -3014,12 +2990,6 @@ i915_gem_object_finish_gpu(struct drm_i915_gem_object *obj)
 	if ((obj->base.read_domains & I915_GEM_GPU_DOMAINS) == 0)
 		return 0;
 
-	if (obj->base.write_domain & I915_GEM_GPU_DOMAINS) {
-		ret = i915_gem_flush_ring(obj->ring, 0, obj->base.write_domain);
-		if (ret)
-			return ret;
-	}
-
 	ret = i915_gem_object_wait_rendering(obj);
 	if (ret)
 		return ret;
@@ -3044,10 +3014,6 @@ i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
 	if (obj->base.write_domain == I915_GEM_DOMAIN_CPU)
 		return 0;
 
-	ret = i915_gem_object_flush_gpu_write_domain(obj);
-	if (ret)
-		return ret;
-
 	if (write || obj->pending_gpu_write) {
 		ret = i915_gem_object_wait_rendering(obj);
 		if (ret)
-- 
1.7.10.4