uxa/glamor: Create glamor pixmap by default.

When creating native glamor pixmaps we will get much better performance
than using the textured-drm pixmap, this commit is to make that the
default behaviour when configured to use glamor. Another advantage
of this commit is that  we reduce the risk of encountering the
"incompatible region exists for this name" and the associated
render corruption. And since we now never intentionally allocate
a reusable pixmap we could just make all (intel_glamor) allocations
non-reusable without incurring too great an overhead.

A side effect is that those glamor pixmaps do not have a
valid BO attached to them and thus it fails to get a DRI drawable. This
commit also fixes that problem by adjusting the fixup_shadow mechanism
to recreate a textured-drm pixmap from the native glamor pixmap. I tested
this with mutter, and it works fine.

The performance gain to apply this patch is about 10% to 20% with
different workload.

Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

3 files changed, 90 insertions, 7 deletions

diff --git a/src/intel_dri.c b/src/intel_dri.c
index df3338f2..46c11d56 100644
--- a/src/intel_dri.c
+++ b/src/intel_dri.c
@@ -66,6 +66,8 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include "dri2.h"
 
+#include "intel_glamor.h"
+
 typedef struct {
 	int refcnt;
 	PixmapPtr pixmap;
@@ -125,6 +127,65 @@ static PixmapPtr get_front_buffer(DrawablePtr drawable)
 	return pixmap;
 }
 
+static PixmapPtr fixup_glamor(DrawablePtr drawable, PixmapPtr pixmap)
+{
+	ScreenPtr screen = drawable->pScreen;
+	ScrnInfoPtr scrn = xf86Screens[screen->myNum];
+	PixmapPtr old = get_drawable_pixmap(drawable);
+	struct intel_pixmap *priv = intel_get_pixmap_private(pixmap);
+	GCPtr gc;
+
+	/* With a glamor pixmap, 2D pixmaps are created in texture
+	 * and without a static BO attached to it. To support DRI,
+	 * we need to create a new textured-drm pixmap and
+	 * need to copy the original content to this new textured-drm
+	 * pixmap, and then convert the old pixmap to a coherent
+	 * textured-drm pixmap which has a valid BO attached to it
+	 * and also has a valid texture, thus both glamor and DRI2
+	 * can access it.
+	 *
+	 */
+
+	/* Copy the current contents of the pixmap to the bo. */
+	gc = GetScratchGC(drawable->depth, screen);
+	if (gc) {
+		ValidateGC(&pixmap->drawable, gc);
+		gc->ops->CopyArea(drawable, &pixmap->drawable,
+				  gc,
+				  0, 0,
+				  drawable->width,
+				  drawable->height,
+				  0, 0);
+		FreeScratchGC(gc);
+	}
+
+	intel_set_pixmap_private(pixmap, NULL);
+	screen->DestroyPixmap(pixmap);
+
+	/* And redirect the pixmap to the new bo (for 3D). */
+	intel_set_pixmap_private(old, priv);
+	old->refcnt++;
+
+	/* This creating should not fail, as we already created its
+	 * successfully. But if it happens, we put a warning indicator
+	 * here, and the old pixmap will still be a glamor pixmap, and
+	 * latter the pixmap_flink will get a 0 name, then the X server
+	 * will pass a BadAlloc to the client.*/
+	if (!intel_glamor_create_textured_pixmap(old))
+		xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+			   "Failed to get DRI drawable for glamor pixmap.\n");
+
+	screen->ModifyPixmapHeader(pixmap,
+				   drawable->width,
+				   drawable->height,
+				   0, 0,
+				   priv->stride,
+				   NULL);
+
+	intel_get_screen_private(xf86Screens[screen->myNum])->needs_flush = TRUE;
+	return old;
+}
+
 static PixmapPtr fixup_shadow(DrawablePtr drawable, PixmapPtr pixmap)
 {
 	ScreenPtr screen = drawable->pScreen;
@@ -203,6 +264,7 @@ I830DRI2CreateBuffers(DrawablePtr drawable, unsigned int *attachments,
 	I830DRI2BufferPrivatePtr privates;
 	PixmapPtr pixmap, pDepthPixmap;
 	int i;
+	int is_glamor_pixmap;
 
 	buffers = calloc(count, sizeof *buffers);
 	if (buffers == NULL)
@@ -222,7 +284,10 @@ I830DRI2CreateBuffers(DrawablePtr drawable, unsigned int *attachments,
 			pixmap = pDepthPixmap;
 			pixmap->refcnt++;
 		}
-		if (pixmap == NULL) {
+
+		is_glamor_pixmap = pixmap && (intel_get_pixmap_private(pixmap) == NULL);
+
+		if (pixmap == NULL || is_glamor_pixmap) {
 			unsigned int hint = INTEL_CREATE_PIXMAP_DRI2;
 
 			if (intel->tiling & INTEL_TILING_3D) {
@@ -255,8 +320,12 @@ I830DRI2CreateBuffers(DrawablePtr drawable, unsigned int *attachments,
 				goto unwind;
 			}
 
-			if (attachment == DRI2BufferFrontLeft)
-				pixmap = fixup_shadow(drawable, pixmap);
+			if (attachment == DRI2BufferFrontLeft) {
+				if (!is_glamor_pixmap)
+					pixmap = fixup_shadow(drawable, pixmap);
+				else
+					pixmap = fixup_glamor(drawable, pixmap);
+			}
 		}
 
 		if (attachments[i] == DRI2BufferDepth)
@@ -317,6 +386,7 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment,
 	DRI2Buffer2Ptr buffer;
 	I830DRI2BufferPrivatePtr privates;
 	PixmapPtr pixmap;
+	int is_glamor_pixmap;
 
 	buffer = calloc(1, sizeof *buffer);
 	if (buffer == NULL)
@@ -330,7 +400,9 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment,
 	pixmap = NULL;
 	if (attachment == DRI2BufferFrontLeft)
 		pixmap = get_front_buffer(drawable);
-	if (pixmap == NULL) {
+
+	is_glamor_pixmap = pixmap && (intel_get_pixmap_private(pixmap) == NULL);
+	if (pixmap == NULL || is_glamor_pixmap) {
 		unsigned int hint = INTEL_CREATE_PIXMAP_DRI2;
 		int pixmap_width = drawable->width;
 		int pixmap_height = drawable->height;
@@ -400,9 +472,12 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment,
 			free(buffer);
 			return NULL;
 		}
-
-		if (attachment == DRI2BufferFrontLeft)
-			pixmap = fixup_shadow(drawable, pixmap);
+		if (attachment == DRI2BufferFrontLeft) {
+			if (!is_glamor_pixmap)
+				pixmap = fixup_shadow(drawable, pixmap);
+			else
+				pixmap = fixup_glamor(drawable, pixmap);
+		}
 	}
 
 	buffer->attachment = attachment;
diff --git a/src/intel_glamor.c b/src/intel_glamor.c
index 669b1b8e..e96daa66 100644
--- a/src/intel_glamor.c
+++ b/src/intel_glamor.c
@@ -36,6 +36,7 @@
 #include <glamor.h>
 
 #include "intel.h"
+#include "i915_drm.h"
 #include "intel_glamor.h"
 #include "uxa.h"
 
@@ -98,6 +99,7 @@ intel_glamor_create_textured_pixmap(PixmapPtr pixmap)
 	priv = intel_get_pixmap_private(pixmap);
 	if (glamor_egl_create_textured_pixmap(pixmap, priv->bo->handle,
 					      priv->stride)) {
+		drm_intel_bo_disable_reuse(priv->bo);
 		priv->pinned = 1;
 		return TRUE;
 	} else
diff --git a/src/intel_uxa.c b/src/intel_uxa.c
index 9d745540..f04a2efd 100644
--- a/src/intel_uxa.c
+++ b/src/intel_uxa.c
@@ -1026,6 +1026,12 @@ intel_uxa_create_pixmap(ScreenPtr screen, int w, int h, int depth,
 	struct intel_pixmap *priv;
 	PixmapPtr pixmap, new_pixmap = NULL;
 
+	if (!(usage & INTEL_CREATE_PIXMAP_DRI2)) {
+		pixmap = intel_glamor_create_pixmap(screen, w, h, depth, usage);
+		if (pixmap)
+			return pixmap;
+	}
+
 	if (w > 32767 || h > 32767)
 		return NullPixmap;