Evas GL: Optimize out calls to eglGetCurrent from the main loop

This is an optimization for EGL only and for the main loop only.

eglGetCurrent{Display,Context,Surface} are expensive calls (they
shouldn't be, but they are). eglMakeCurrent is also very expensive,
so we want as much as possible to avoid calling those functions.
Store the pointers for the main loop as static variables.

Valgrind stats for a quick scrolling session in elm_test:

Before this patch:
 - eglGetCurrentContext ~ 0.4%
 - eglGetCurrentDisplay ~ 0.4%

After this patch:
 - evas_eglGetCurrentContext ~ 0.02%
 - evas_eglGetCurrentDisplay ~ 0.02%

3 files changed, 93 insertions, 36 deletions

diff --git a/src/modules/evas/engines/gl_x11/evas_engine.c b/src/modules/evas/engines/gl_x11/evas_engine.c
index 75a389205d..0d12b744cd 100644
--- a/src/modules/evas/engines/gl_x11/evas_engine.c
+++ b/src/modules/evas/engines/gl_x11/evas_engine.c
@@ -158,6 +158,65 @@ evgl_eng_evas_surface_get(void *data)
       return NULL;
 }
 
+#ifdef GL_GLES
+static EGLDisplay main_dpy  = EGL_NO_DISPLAY;
+static EGLSurface main_draw = EGL_NO_SURFACE;
+static EGLSurface main_read = EGL_NO_SURFACE;
+static EGLContext main_ctx  = EGL_NO_CONTEXT;
+
+EGLContext
+evas_eglGetCurrentContext(void)
+{
+   if (eina_main_loop_is())
+     return main_ctx;
+   else
+     return eglGetCurrentContext();
+}
+
+EGLSurface
+evas_eglGetCurrentSurface(EGLint readdraw)
+{
+   if (eina_main_loop_is())
+     return (readdraw == EGL_READ) ? main_read : main_draw;
+   else
+     return eglGetCurrentSurface(readdraw);
+}
+
+EGLDisplay
+evas_eglGetCurrentDisplay(void)
+{
+   if (eina_main_loop_is())
+     return main_dpy;
+   else
+     return eglGetCurrentDisplay();
+}
+
+EGLBoolean
+evas_eglMakeCurrent(EGLDisplay dpy, EGLSurface draw, EGLSurface read, EGLContext ctx)
+{
+   if (eina_main_loop_is())
+     {
+        EGLBoolean ret;
+
+        if ((dpy == main_dpy) && (draw == main_draw) &&
+            (read == main_read) && (ctx == main_ctx))
+          return 1;
+
+        ret = eglMakeCurrent(dpy, draw, read, ctx);
+        if (ret)
+          {
+             main_dpy  = dpy;
+             main_draw = draw;
+             main_read = read;
+             main_ctx  = ctx;
+          }
+        return ret;
+     }
+   else
+     return eglMakeCurrent(dpy, draw, read, ctx);
+}
+#endif
+
 static int
 evgl_eng_make_current(void *data, void *surface, void *context, int flush)
 {
@@ -172,7 +231,6 @@ evgl_eng_make_current(void *data, void *surface, void *context, int flush)
         return 0;
      }
 
-
 #ifdef GL_GLES
    EGLContext ctx = (EGLContext)context;
    EGLSurface sfc = (EGLSurface)surface;
@@ -180,25 +238,21 @@ evgl_eng_make_current(void *data, void *surface, void *context, int flush)
 
    if ((!context) && (!surface))
      {
-        if (!eglGetCurrentContext() &&
-            !eglGetCurrentSurface(EGL_READ) &&
-            !eglGetCurrentSurface(EGL_DRAW))
-          return 1;
-        ret = eglMakeCurrent(dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
+        ret = evas_eglMakeCurrent(dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
         if (!ret)
           {
              int err = eglGetError();
              glsym_evas_gl_common_error_set(err - EGL_SUCCESS);
-             ERR("eglMakeCurrent() failed! Error Code=%#x", err);
+             ERR("evas_eglMakeCurrent() failed! Error Code=%#x", err);
              return 0;
           }
         return 1;
      }
 
    // FIXME: Check (eglGetCurrentDisplay() != dpy) ?
-   if ((eglGetCurrentContext() != ctx) ||
-       (eglGetCurrentSurface(EGL_READ) != sfc) ||
-       (eglGetCurrentSurface(EGL_DRAW) != sfc) )
+   if ((evas_eglGetCurrentContext() != ctx) ||
+       (evas_eglGetCurrentSurface(EGL_READ) != sfc) ||
+       (evas_eglGetCurrentSurface(EGL_DRAW) != sfc) )
      {
 
         //!!!! Does it need to be flushed with it's set to NULL above??
@@ -206,13 +260,13 @@ evgl_eng_make_current(void *data, void *surface, void *context, int flush)
         if (flush) eng_window_use(NULL);
 
         // Do a make current
-        ret = eglMakeCurrent(dpy, sfc, sfc, ctx);
+        ret = evas_eglMakeCurrent(dpy, sfc, sfc, ctx);
 
         if (!ret)
           {
              int err = eglGetError();
              glsym_evas_gl_common_error_set(err - EGL_SUCCESS);
-             ERR("eglMakeCurrent() failed! Error Code=%#x", err);
+             ERR("evas_eglMakeCurrent() failed! Error Code=%#x", err);
              return 0;
           }
      }
@@ -662,7 +716,7 @@ evgl_eng_pbuffer_surface_create(void *data, EVGL_Surface *sfc,
    config_attrs[i++] = EGL_PBUFFER_BIT;
    config_attrs[i++] = EGL_NONE;
 #else
-   // It looks like eglMakeCurrent might fail if we use a different config from
+   // It looks like evas_eglMakeCurrent might fail if we use a different config from
    // the actual display surface. This is weird.
    i = 0;
    config_attrs[i++] = EGL_CONFIG_ID;
@@ -1121,7 +1175,7 @@ evgl_eng_gles_context_create(void *data,
 
    if (!sfc || !sfc->indirect_sfc_config)
      {
-        ERR("Surface is not set! Creating context anyways but eglMakeCurrent "
+        ERR("Surface is not set! Creating context anyways but evas_eglMakeCurrent "
             "might very well fail with EGL_BAD_MATCH (0x3009)");
         config = eng_get_ob(re)->egl_config;
      }
@@ -1833,7 +1887,7 @@ eng_preload_make_current(void *data, void *doit)
    if (doit)
      {
 #ifdef GL_GLES
-        if (!eglMakeCurrent(ob->egl_disp, ob->egl_surface[0], ob->egl_surface[0], ob->egl_context[0]))
+        if (!evas_eglMakeCurrent(ob->egl_disp, ob->egl_surface[0], ob->egl_surface[0], ob->egl_context[0]))
           return EINA_FALSE;
 #else
         if (!__glXMakeContextCurrent(ob->info->info.display, ob->glxwin, ob->context))
@@ -1848,7 +1902,7 @@ eng_preload_make_current(void *data, void *doit)
    else
      {
 #ifdef GL_GLES
-        if (!eglMakeCurrent(ob->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT))
+        if (!evas_eglMakeCurrent(ob->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT))
           return EINA_FALSE;
 #else
         if (!__glXMakeContextCurrent(ob->info->info.display, 0, NULL))
@@ -1895,7 +1949,7 @@ eng_gl_current_context_get(void *data EINA_UNUSED)
    context = glsym_evgl_current_native_context_get(ctx);
 
 #ifdef GL_GLES
-   if (eglGetCurrentContext() == context)
+   if (evas_eglGetCurrentContext() == context)
      return ctx;
 #else
    if (glXGetCurrentContext() == context)
diff --git a/src/modules/evas/engines/gl_x11/evas_engine.h b/src/modules/evas/engines/gl_x11/evas_engine.h
index 3ef4054e10..f84313b16f 100644
--- a/src/modules/evas/engines/gl_x11/evas_engine.h
+++ b/src/modules/evas/engines/gl_x11/evas_engine.h
@@ -214,7 +214,12 @@ _re_wincheck(Outbuf *ob)
    return 0;
 }
 
-#ifndef GL_GLES
+#ifdef GL_GLES
+EGLBoolean evas_eglMakeCurrent(EGLDisplay dpy, EGLSurface draw, EGLSurface read, EGLContext ctx);
+EGLContext evas_eglGetCurrentContext(void);
+EGLSurface evas_eglGetCurrentSurface(EGLint readdraw);
+EGLDisplay evas_eglGetCurrentDisplay(void);
+#else
 Eina_Bool __glXMakeContextCurrent(Display *disp, GLXDrawable glxwin,
                                   GLXContext context);
 #endif
diff --git a/src/modules/evas/engines/gl_x11/evas_x_main.c b/src/modules/evas/engines/gl_x11/evas_x_main.c
index d6073aad8e..8ee32d2dde 100644
--- a/src/modules/evas/engines/gl_x11/evas_x_main.c
+++ b/src/modules/evas/engines/gl_x11/evas_x_main.c
@@ -276,12 +276,12 @@ try_gles2:
      _tls_context_set(gw->egl_context[0]);
    
    SET_RESTORE_CONTEXT();
-   if (eglMakeCurrent(gw->egl_disp,
+   if (evas_eglMakeCurrent(gw->egl_disp,
                       gw->egl_surface[0],
                       gw->egl_surface[0],
                       gw->egl_context[0]) == EGL_FALSE)
      {
-        ERR("eglMakeCurrent() fail. code=%#x", eglGetError());
+        ERR("evas_eglMakeCurrent() fail. code=%#x", eglGetError());
         eng_window_free(gw);
         return NULL;
      }
@@ -591,7 +591,7 @@ eng_window_free(Outbuf *gw)
      }
 #ifdef GL_GLES
    SET_RESTORE_CONTEXT();
-   eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
+   evas_eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
    if (gw->egl_surface[0] != EGL_NO_SURFACE)
       eglDestroySurface(gw->egl_disp, gw->egl_surface[0]);
    if (gw->egl_surface[1] != EGL_NO_SURFACE)
@@ -632,12 +632,12 @@ eng_window_make_current(void *data, void *doit)
    SET_RESTORE_CONTEXT();
    if (doit)
      {
-        if (!eglMakeCurrent(gw->egl_disp, gw->egl_surface[0], gw->egl_surface[0], gw->egl_context[0]))
+        if (!evas_eglMakeCurrent(gw->egl_disp, gw->egl_surface[0], gw->egl_surface[0], gw->egl_context[0]))
           return EINA_FALSE;
      }
    else
      {
-        if (!eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT))
+        if (!evas_eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT))
           return EINA_FALSE;
      }
 #else
@@ -670,15 +670,13 @@ eng_window_use(Outbuf *gw)
 #ifdef GL_GLES
    if (xwin)
      {
-        if ((eglGetCurrentDisplay() !=
-             xwin->egl_disp) ||
-            (eglGetCurrentContext() !=
-             xwin->egl_context[0])
+        if ((evas_eglGetCurrentDisplay() != xwin->egl_disp) ||
+            (evas_eglGetCurrentContext() != xwin->egl_context[0])
 #if 0
             // FIXME: Figure out what that offscreen thing was about...
-            || (eglGetCurrentSurface(EGL_READ) !=
+            || (evas_eglGetCurrentSurface(EGL_READ) !=
                 xwin->egl_surface[xwin->offscreen])
-            || (eglGetCurrentSurface(EGL_DRAW) !=
+            || (evas_eglGetCurrentSurface(EGL_DRAW) !=
                 xwin->egl_surface[xwin->offscreen])
 #endif
             )
@@ -706,12 +704,12 @@ eng_window_use(Outbuf *gw)
              if (gw->egl_surface[0] != EGL_NO_SURFACE)
                {
                   SET_RESTORE_CONTEXT();
-                  if (eglMakeCurrent(gw->egl_disp,
+                  if (evas_eglMakeCurrent(gw->egl_disp,
                                      gw->egl_surface[0],
                                      gw->egl_surface[0],
                                      gw->egl_context[0]) == EGL_FALSE)
                     {
-                       ERR("eglMakeCurrent() failed!");
+                       ERR("evas_eglMakeCurrent() failed!");
                     }
                }
 // GLX
@@ -742,7 +740,7 @@ eng_window_unsurf(Outbuf *gw)
    if (xwin == gw)
      {
         SET_RESTORE_CONTEXT();
-        eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
+        evas_eglMakeCurrent(gw->egl_disp, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
         if (gw->egl_surface[0] != EGL_NO_SURFACE)
            eglDestroySurface(gw->egl_disp, gw->egl_surface[0]);
         gw->egl_surface[0] = EGL_NO_SURFACE;
@@ -777,12 +775,12 @@ eng_window_resurf(Outbuf *gw)
         return;
      }
    SET_RESTORE_CONTEXT();
-   if (eglMakeCurrent(gw->egl_disp,
+   if (evas_eglMakeCurrent(gw->egl_disp,
                       gw->egl_surface[0],
                       gw->egl_surface[0],
                       gw->egl_context[0]) == EGL_FALSE)
      {
-        ERR("eglMakeCurrent() failed!");
+        ERR("evas_eglMakeCurrent() failed!");
      }
 #else
    Evas_GL_X11_Visual *evis;
@@ -1332,10 +1330,10 @@ eng_gl_context_use(Context_3D *ctx)
 {
 #if GL_GLES
     SET_RESTORE_CONTEXT();
-   if (eglMakeCurrent(ctx->display, ctx->surface,
+   if (evas_eglMakeCurrent(ctx->display, ctx->surface,
                       ctx->surface, ctx->context) == EGL_FALSE)
      {
-        ERR("eglMakeCurrent() failed.");
+        ERR("evas_eglMakeCurrent() failed.");
      }
 #else
    if (!__glXMakeContextCurrent(ctx->display, ctx->glxwin, ctx->context))