AIGLX: Zero-copy texture-from-pixmap.

When available, use the 2D driver texOffsetStart hook and the 3D driver
setTexOffset hook to save the overhead of passing the pixmap data to
glTex(Sub)Image.

The basic idea is to update the driver specific 'offset' for bound pixmaps
before dispatching a GLX render request and to flush immediately afterwards
if there are any pixmaps bound. This should ensure that the 3D driver can
use pixmaps for texturing directly regardless of the X server moving them
around.

GL/glx/glxdrawable.h

@@ -42,6 +42,10 @@
 
 #include <damage.h>
 
+#ifdef XF86DRI
+#include <GL/internal/dri_interface.h>
+#endif
+
 typedef struct {
 
     DrawablePtr pDraw;
@@ -50,7 +54,12 @@ typedef struct {
     ScreenPtr pScreen;
     Bool idExists;
     int refcnt;
+#ifdef XF86DRI
     DamagePtr pDamage;
+    __DRIcontext *pDRICtx;
+    GLint texname;
+    unsigned long offset;
+#endif
 } __GLXpixmap;
 
 struct __GLXdrawable {

GL/glx/glxdri.c

@@ -76,6 +76,11 @@ struct __GLXDRIscreen {
     xf86EnterVTProc *enterVT;
     xf86LeaveVTProc *leaveVT;
 
+    DRITexOffsetStartProcPtr texOffsetStart;
+    DRITexOffsetFinishProcPtr texOffsetFinish;
+    __GLXpixmap* texOffsetOverride[16];
+    GLuint lastTexOffsetOverride;
+
     unsigned char glx_enable_bits[__GLX_EXT_BYTES];
 };
 
@@ -125,30 +130,75 @@ struct __GLXDRIdrawable {
 static const char CREATE_NEW_SCREEN_FUNC[] =
     "__driCreateNewScreen_" STRINGIFY (INTERNAL_VERSION);
 
-/* The DRI driver entry point version wasn't bumped when the
- * copySubBuffer functionality was added to the DRI drivers, but the
- * functionality is still conditional on the value of the
- * internal_api_version passed to __driCreateNewScreen.  However, the
- * screen constructor doesn't fail for a DRI driver that's older than
- * the passed in version number, so there's no way we can know for
- * sure that we can actually use the copySubBuffer functionality.  But
- * since the earliest (and at this point only) released mesa version
- * (6.5) that uses the 20050727 entry point does have copySubBuffer,
- * we'll just settle for that.  We still have to pass in a higher to
- * the screen constructor to enable the functionality.
- */
-#define COPY_SUB_BUFFER_INTERNAL_VERSION 20060314
 
 static void
-__glXDRIleaveServer(void)
+__glXDRIleaveServer(GLboolean rendering)
 {
-  DRIBlockHandler(NULL, NULL, NULL);
+    int i;
+
+    for (i = 0; rendering && i < screenInfo.numScreens; i++) {
+	__GLXDRIscreen * const screen =
+	    (__GLXDRIscreen *) __glXgetActiveScreen(i);
+	GLuint lastOverride = screen->lastTexOffsetOverride;
+
+	if (lastOverride) {
+	    __GLXpixmap **texOffsetOverride = screen->texOffsetOverride;
+	    int j;
+
+	    for (j = 0; j < lastOverride; j++) {
+		__GLXpixmap *pGlxPix = texOffsetOverride[j];
+
+		if (pGlxPix && pGlxPix->texname) {
+		    pGlxPix->offset =
+			screen->texOffsetStart((PixmapPtr)pGlxPix->pDraw);
+		}
+	    }
+	}
+    }
+
+    DRIBlockHandler(NULL, NULL, NULL);
+
+    for (i = 0; rendering && i < screenInfo.numScreens; i++) {
+	__GLXDRIscreen * const screen =
+	    (__GLXDRIscreen *) __glXgetActiveScreen(i);
+	GLuint lastOverride = screen->lastTexOffsetOverride;
+
+	if (lastOverride) {
+	    __GLXpixmap **texOffsetOverride = screen->texOffsetOverride;
+	    int j;
+
+	    for (j = 0; j < lastOverride; j++) {
+		__GLXpixmap *pGlxPix = texOffsetOverride[j];
+
+		if (pGlxPix && pGlxPix->texname) {
+		    screen->driScreen.setTexOffset(pGlxPix->pDRICtx,
+						   pGlxPix->texname,
+						   pGlxPix->offset,
+						   pGlxPix->pDraw->depth,
+						   ((PixmapPtr)pGlxPix->pDraw)->
+						   devKind);
+		}
+	    }
+	}
+    }
 }
     
 static void
-__glXDRIenterServer(void)
+__glXDRIenterServer(GLboolean rendering)
 {
-  DRIWakeupHandler(NULL, 0, NULL);
+    int i;
+
+    for (i = 0; rendering && i < screenInfo.numScreens; i++) {
+	__GLXDRIscreen * const screen =
+	    (__GLXDRIscreen *) __glXgetActiveScreen(i);
+
+	if (screen->lastTexOffsetOverride) {
+	    CALL_Flush(GET_DISPATCH(), ());
+	    break;
+	}
+    }
+
+    DRIWakeupHandler(NULL, 0, NULL);
 }
 
 /**
@@ -289,19 +339,6 @@ __glXDRIcontextForceCurrent(__GLXcontext *baseContext)
 					      &context->driContext);
 }
 
-static int
-glxCountBits(int word)
-{
-    int ret = 0;
-
-    while (word) {
-        ret += (word & 1);
-        word >>= 1;
-    }
-
-    return ret;
-}
-
 static void
 glxFillAlphaChannel (PixmapPtr pixmap, int x, int y, int width, int height)
 {
@@ -335,19 +372,75 @@ __glXDRIbindTexImage(__GLXcontext *baseContext,
 		     int buffer,
 		     __GLXpixmap *glxPixmap)
 {
-    RegionPtr	pRegion;
+    RegionPtr	pRegion = NULL;
     PixmapPtr	pixmap;
-    int		bpp;
+    int		w, h, bpp, override = 0;
     GLenum	target, format, type;
+    ScreenPtr pScreen = glxPixmap->pScreen;
+    __GLXDRIscreen * const screen =
+	(__GLXDRIscreen *) __glXgetActiveScreen(pScreen->myNum);
 
     pixmap = (PixmapPtr) glxPixmap->pDraw;
-    if (!glxPixmap->pDamage) {
+    w = pixmap->drawable.width;
-        glxPixmap->pDamage = DamageCreate(NULL, NULL, DamageReportNone,
+    h = pixmap->drawable.height;
-					  TRUE, glxPixmap->pScreen, NULL);
+
-	if (!glxPixmap->pDamage)
+    if (h & (h - 1) || w & (w - 1))
-            return BadAlloc;
+	target = GL_TEXTURE_RECTANGLE_ARB;
+    else
+	target = GL_TEXTURE_2D;
+
+    if (screen->texOffsetStart && screen->driScreen.setTexOffset) {
+	__GLXpixmap **texOffsetOverride = screen->texOffsetOverride;
+	int i, firstEmpty = 16, texname;
+
+	for (i = 0; i < 16; i++) {
+	    if (texOffsetOverride[i] == glxPixmap)
+		goto alreadyin; 
+
+	    if (firstEmpty == 16 && !texOffsetOverride[i])
+		firstEmpty = i;
+	}
+
+	if (firstEmpty == 16) {
+	    ErrorF("%s: Failed to register texture offset override\n", __func__);
+	    goto nooverride;
+	}
+
+	if (firstEmpty >= screen->lastTexOffsetOverride)
+	    screen->lastTexOffsetOverride = firstEmpty + 1;
+
+	texOffsetOverride[firstEmpty] = glxPixmap;
+
+alreadyin:
+	override = 1;
+
+	glxPixmap->pDRICtx = &((__GLXDRIcontext*)baseContext)->driContext;
+
+	CALL_GetIntegerv(GET_DISPATCH(), (target == GL_TEXTURE_2D ?
+					  GL_TEXTURE_BINDING_2D :
+					  GL_TEXTURE_BINDING_RECTANGLE_NV,
+					  &texname));
+
+	if (texname == glxPixmap->texname)
+	    return Success;
+
+	glxPixmap->texname = texname;
+
+	screen->driScreen.setTexOffset(glxPixmap->pDRICtx, texname, 0,
+				       pixmap->drawable.depth, pixmap->devKind);
+    }
+nooverride:
+
+    if (!glxPixmap->pDamage) {
+	if (!override) {
+	    glxPixmap->pDamage = DamageCreate(NULL, NULL, DamageReportNone,
+					      TRUE, pScreen, NULL);
+	    if (!glxPixmap->pDamage)
+		return BadAlloc;
+
+	    DamageRegister ((DrawablePtr) pixmap, glxPixmap->pDamage);
+	}
 
-	DamageRegister ((DrawablePtr) pixmap, glxPixmap->pDamage);
 	pRegion = NULL;
     } else {
 	pRegion = DamageRegion(glxPixmap->pDamage);
@@ -360,30 +453,22 @@ __glXDRIbindTexImage(__GLXcontext *baseContext,
 	bpp = 4;
 	format = GL_BGRA;
 	type =
-#if X_BYTE_ORDER == X_LITTLE_ENDIAN
+#if X_BYTE_ORDER == X_BIG_ENDIAN
-	    GL_UNSIGNED_BYTE;
+	    !override ? GL_UNSIGNED_INT_8_8_8_8_REV :
-#else
-	    GL_UNSIGNED_INT_8_8_8_8_REV;
 #endif
+	    GL_UNSIGNED_BYTE;
     } else {
 	bpp = 2;
 	format = GL_RGB;
 	type = GL_UNSIGNED_SHORT_5_6_5;
     }
 
-    if (!(glxCountBits(pixmap->drawable.width) == 1 &&
-	  glxCountBits(pixmap->drawable.height) == 1)
-	/* || strstr(CALL_GetString(GL_EXTENSIONS,
-	             "GL_ARB_texture_non_power_of_two")) */)
-	target = GL_TEXTURE_RECTANGLE_ARB;
-    else
-	target = GL_TEXTURE_2D;
-
     CALL_PixelStorei( GET_DISPATCH(), (GL_UNPACK_ROW_LENGTH,
 				       pixmap->devKind / bpp) );
+
     if (pRegion == NULL)
     {
-	if (pixmap->drawable.depth == 24)
+	if (!override && pixmap->drawable.depth == 24)
 	    glxFillAlphaChannel(pixmap,
 				pixmap->drawable.x,
 				pixmap->drawable.y,
@@ -404,8 +489,8 @@ __glXDRIbindTexImage(__GLXcontext *baseContext,
 			  0,
 			  format,
 			  type,
-			  pixmap->devPrivate.ptr) );
+			  override ? NULL : pixmap->devPrivate.ptr) );
-    } else {
+    } else if (!override) {
         int i, numRects;
 	BoxPtr p;
 
@@ -436,7 +521,8 @@ __glXDRIbindTexImage(__GLXcontext *baseContext,
 	}
     }
 
-    DamageEmpty(glxPixmap->pDamage);
+    if (!override)
+	DamageEmpty(glxPixmap->pDamage);
 
     return Success;
 }
@@ -446,6 +532,40 @@ __glXDRIreleaseTexImage(__GLXcontext *baseContext,
 			int buffer,
 			__GLXpixmap *pixmap)
 {
+    ScreenPtr pScreen = pixmap->pScreen;
+    __GLXDRIscreen * const screen =
+	(__GLXDRIscreen *) __glXgetActiveScreen(pScreen->myNum);
+    GLuint lastOverride = screen->lastTexOffsetOverride;
+
+    if (lastOverride) {
+	__GLXpixmap **texOffsetOverride = screen->texOffsetOverride;
+	int i;
+
+	for (i = 0; i < lastOverride; i++) {
+	    if (texOffsetOverride[i] == pixmap) {
+		if (screen->texOffsetFinish)
+		    screen->texOffsetFinish((PixmapPtr)pixmap->pDraw);
+
+		texOffsetOverride[i] = NULL;
+
+		if (i + 1 == lastOverride) {
+		    lastOverride = 0;
+
+		    while (i--) {
+			if (texOffsetOverride[i]) {
+			    lastOverride = i + 1;
+			    break;
+			}
+		    }
+
+		    screen->lastTexOffsetOverride = lastOverride;
+
+		    break;
+		}
+	    }
+	}
+    }
+
     return Success;
 }
 
@@ -666,9 +786,9 @@ static GLboolean createContext(__DRInativeDisplay *dpy, int screen,
     fakeID = FakeClientID(0);
     *(XID *) contextID = fakeID;
 
-    __glXDRIenterServer();
+    __glXDRIenterServer(GL_FALSE);
     retval = DRICreateContext(pScreen, visual, fakeID, hw_context);
-    __glXDRIleaveServer();
+    __glXDRIleaveServer(GL_FALSE);
     return retval;
 }
 
@@ -677,9 +797,9 @@ static GLboolean destroyContext(__DRInativeDisplay *dpy, int screen,
 {
     GLboolean retval;
 
-    __glXDRIenterServer();
+    __glXDRIenterServer(GL_FALSE);
     retval = DRIDestroyContext(screenInfo.screens[screen], context);
-    __glXDRIleaveServer();
+    __glXDRIleaveServer(GL_FALSE);
     return retval;
 }
 
@@ -694,12 +814,12 @@ createDrawable(__DRInativeDisplay *dpy, int screen,
     if (!pDrawable)
 	return GL_FALSE;
 
-    __glXDRIenterServer();
+    __glXDRIenterServer(GL_FALSE);
     retval = DRICreateDrawable(screenInfo.screens[screen],
 			    drawable,
 			    pDrawable,
 			    hHWDrawable);
-    __glXDRIleaveServer();
+    __glXDRIleaveServer(GL_FALSE);
     return retval;
 }
 
@@ -713,11 +833,11 @@ destroyDrawable(__DRInativeDisplay *dpy, int screen, __DRIid drawable)
     if (!pDrawable)
 	return GL_FALSE;
 
-    __glXDRIenterServer();
+    __glXDRIenterServer(GL_FALSE);
     retval = DRIDestroyDrawable(screenInfo.screens[screen],
 			     drawable,
 			     pDrawable);
-    __glXDRIleaveServer();
+    __glXDRIleaveServer(GL_FALSE);
     return retval;
 }
 
@@ -754,14 +874,14 @@ getDrawableInfo(__DRInativeDisplay *dpy, int screen,
 	return GL_FALSE;
     }
 
-    __glXDRIenterServer();
+    __glXDRIenterServer(GL_FALSE);
     retval = DRIGetDrawableInfo(screenInfo.screens[screen],
 				pDrawable, index, stamp,
 				x, y, width, height,
 				numClipRects, &pClipRects,
 				backX, backY,
 				numBackClipRects, &pBackClipRects);
-    __glXDRIleaveServer();
+    __glXDRIleaveServer(GL_FALSE);
 
     if (*numClipRects > 0) {
 	size = sizeof (drm_clip_rect_t) * *numClipRects;
@@ -866,7 +986,7 @@ __glXDRIscreenProbe(ScreenPtr pScreen)
     __DRIframebuffer  framebuffer;
     int   fd = -1;
     int   status;
-    int api_ver = COPY_SUB_BUFFER_INTERNAL_VERSION;
+    int api_ver = 20070121;
     drm_magic_t magic;
     drmVersionPtr version;
     int newlyopened;
@@ -1048,6 +1168,9 @@ __glXDRIscreenProbe(ScreenPtr pScreen)
 	goto handle_error;
     }
 
+    DRIGetTexOffsetFuncs(pScreen, &screen->texOffsetStart,
+			 &screen->texOffsetFinish);
+
     __glXScreenInit(&screen->base, pScreen);
 
     buffer_size = __glXGetExtensionString(screen->glx_enable_bits, NULL);

GL/glx/glxext.c

@@ -238,9 +238,9 @@ GLboolean __glXFreeContext(__GLXcontext *cx)
      * the latter case we need to lift the DRI lock manually. */
 
     if (!glxBlockClients) {
-	__glXleaveServer();
+	__glXleaveServer(GL_FALSE);
 	cx->destroy(cx);
-	__glXenterServer();
+	__glXenterServer(GL_FALSE);
     } else {
 	cx->next = glxPendingDestroyContexts;
 	glxPendingDestroyContexts = cx;
@@ -439,49 +439,49 @@ void glxResumeClients(void)
 	AttendClient(__glXClients[i]->client);
     }
 
-    __glXleaveServer();
+    __glXleaveServer(GL_FALSE);
     for (cx = glxPendingDestroyContexts; cx != NULL; cx = next) {
 	next = cx->next;
 
 	cx->destroy(cx);
     }
     glxPendingDestroyContexts = NULL;
-    __glXenterServer();
+    __glXenterServer(GL_FALSE);
 }
 
 static void
-__glXnopEnterServer(void)
+__glXnopEnterServer(GLboolean rendering)
 {
 }
     
 static void
-__glXnopLeaveServer(void)
+__glXnopLeaveServer(GLboolean rendering)
 {
 }
 
-static void (*__glXenterServerFunc)(void) = __glXnopEnterServer;
+static void (*__glXenterServerFunc)(GLboolean) = __glXnopEnterServer;
-static void (*__glXleaveServerFunc)(void)  = __glXnopLeaveServer;
+static void (*__glXleaveServerFunc)(GLboolean)  = __glXnopLeaveServer;
 
-void __glXsetEnterLeaveServerFuncs(void (*enter)(void),
+void __glXsetEnterLeaveServerFuncs(void (*enter)(GLboolean),
-				   void (*leave)(void))
+				   void (*leave)(GLboolean))
 {
   __glXenterServerFunc = enter;
   __glXleaveServerFunc = leave;
 }
 
 
-void __glXenterServer(void)
+void __glXenterServer(GLboolean rendering)
 {
   glxServerLeaveCount--;
 
   if (glxServerLeaveCount == 0)
-    (*__glXenterServerFunc)();
+    (*__glXenterServerFunc)(rendering);
 }
 
-void __glXleaveServer(void)
+void __glXleaveServer(GLboolean rendering)
 {
   if (glxServerLeaveCount == 0)
-    (*__glXleaveServerFunc)();
+    (*__glXleaveServerFunc)(rendering);
 
   glxServerLeaveCount++;
 }
@@ -546,11 +546,12 @@ static int __glXDispatch(ClientPtr client)
 								       opcode,
 								       client->swapped);
     if (proc != NULL) {
-	__glXleaveServer();
+	GLboolean rendering = opcode <= X_GLXRenderLarge;
+	__glXleaveServer(rendering);
 
 	retval = (*proc)(cl, (GLbyte *) stuff);
 
-	__glXenterServer();
+	__glXenterServer(rendering);
     }
     else {
 	retval = BadRequest;

GL/glx/glxglcore.c

@@ -106,11 +106,11 @@ __glXMesaDrawableSwapBuffers(__GLXdrawable *base)
      * why we need to re-take the lock and swap in the server context
      * before calling XMesaSwapBuffers() here.  /me shakes head. */
 
-    __glXenterServer();
+    __glXenterServer(GL_FALSE);
 
     XMesaSwapBuffers(glxPriv->xm_buf);
 
-    __glXleaveServer();
+    __glXleaveServer(GL_FALSE);
 
     return GL_TRUE;
 }

GL/glx/glxserver.h

@@ -131,10 +131,10 @@ struct __GLXprovider {
 
 void GlxPushProvider(__GLXprovider *provider);
 
-void __glXsetEnterLeaveServerFuncs(void (*enter)(void),
+void __glXsetEnterLeaveServerFuncs(void (*enter)(GLboolean),
-				   void (*leave)(void));
+				   void (*leave)(GLboolean));
-void __glXenterServer(void);
+void __glXenterServer(GLboolean rendering);
-void __glXleaveServer(void);
+void __glXleaveServer(GLboolean rendering);
 
 void glxSuspendClients(void);
 void glxResumeClients(void);