sna: Allow inplace uploads to utilise GTT on LLC machines

Rather than arbitrarily disable the fallback paths for LLC, allow it to
utilise any available GTT buffers for inplace uploads. The best
explanation so far is that with the streaming is that we are trashing
the LLC. On other machines, the difference is in the noise.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 10 insertions, 12 deletions

diff --git a/src/sna/kgem.c b/src/sna/kgem.c
index e8ac5c2c..ef8cddee 100644
--- a/src/sna/kgem.c
+++ b/src/sna/kgem.c
@@ -5026,9 +5026,6 @@ struct kgem_bo *kgem_create_buffer(struct kgem *kgem,
 	/* we should never be asked to create anything TOO large */
 	assert(size <= kgem->max_object_size);
 
-	if (kgem->has_llc)
-		flags &= ~KGEM_BUFFER_INPLACE;
-
 #if !DBG_NO_UPLOAD_CACHE
 	list_for_each_entry(bo, &kgem->batch_buffers, base.list) {
 		assert(bo->base.io);
@@ -5109,8 +5106,13 @@ struct kgem_bo *kgem_create_buffer(struct kgem *kgem,
 		alloc = ALIGN(size, kgem->buffer_size);
 	if (alloc > MAX_CACHE_SIZE)
 		alloc = PAGE_ALIGN(size);
+
+	if (alloc > kgem->aperture_mappable / 4)
+		flags &= ~KGEM_BUFFER_INPLACE;
 	alloc /= PAGE_SIZE;
-	if (kgem->has_llc) {
+
+	if (kgem->has_llc &&
+	    (flags & KGEM_BUFFER_WRITE_INPLACE) != KGEM_BUFFER_WRITE_INPLACE) {
 		bo = buffer_alloc();
 		if (bo == NULL)
 			goto skip_llc;
@@ -5147,6 +5149,7 @@ struct kgem_bo *kgem_create_buffer(struct kgem *kgem,
 		if (bo->mem) {
 			if (flags & KGEM_BUFFER_WRITE)
 				kgem_bo_sync__cpu(kgem, &bo->base);
+			flags &= ~KGEM_BUFFER_INPLACE;
 			goto init;
 		} else {
 			bo->base.refcnt = 0; /* for valgrind */
@@ -5155,9 +5158,6 @@ struct kgem_bo *kgem_create_buffer(struct kgem *kgem,
 	}
 skip_llc:
 
-	if (PAGE_SIZE * alloc > kgem->aperture_mappable / 4)
-		flags &= ~KGEM_BUFFER_INPLACE;
-
 	if ((flags & KGEM_BUFFER_WRITE_INPLACE) == KGEM_BUFFER_WRITE_INPLACE) {
 		/* The issue with using a GTT upload buffer is that we may
 		 * cause eviction-stalls in order to free up some GTT space.
@@ -5220,7 +5220,7 @@ skip_llc:
 			bo->mem = kgem_bo_map(kgem, &bo->base);
 			if (bo->mem) {
 				if (IS_CPU_MAP(bo->base.map))
-				    flags &= ~KGEM_BUFFER_INPLACE;
+					flags &= ~KGEM_BUFFER_INPLACE;
 				goto init;
 			} else {
 				bo->base.refcnt = 0;
@@ -5244,12 +5244,10 @@ skip_llc:
 			goto init;
 		}
 
-		if ((flags & KGEM_BUFFER_WRITE_INPLACE) != KGEM_BUFFER_WRITE_INPLACE) {
+		if ((flags & KGEM_BUFFER_INPLACE) == 0) {
 			bo = create_snoopable_buffer(kgem, alloc);
-			if (bo) {
-				assert((flags & KGEM_BUFFER_INPLACE) == 0);
+			if (bo)
 				goto init;
-			}
 		}
 	}