[gegl/threaded-base-classes: 13/13] factor out check if threading should be used

[Øyvind Kolås <ok src gnome org>]

commit e25e7d08cd89b6dabed523130705d32d85a8c0b8
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri Jun 27 00:41:20 2014 +0200

    factor out check if threading should be used
    
    Also opt out of multi-threading if the op has an opencl
    implementation and opencl is enabled.

 gegl/operation/gegl-operation-composer.c  |    8 ++------
 gegl/operation/gegl-operation-composer3.c |    4 ++--
 gegl/operation/gegl-operation-filter.c    |    8 ++------
 gegl/operation/gegl-operation-source.c    |    9 ++-------
 gegl/operation/gegl-operation.c           |   24 ++++++++++++++++++++++++
 gegl/operation/gegl-operation.h           |    4 ++++
 6 files changed, 36 insertions(+), 21 deletions(-)
---
diff --git a/gegl/operation/gegl-operation-composer.c b/gegl/operation/gegl-operation-composer.c
index 6617842..1a1579f 100644
--- a/gegl/operation/gegl-operation-composer.c
+++ b/gegl/operation/gegl-operation-composer.c
@@ -137,7 +137,6 @@ gegl_operation_composer_process (GeglOperation        *operation,
                                  gint                  level)
 {
   GeglOperationComposerClass *klass   = GEGL_OPERATION_COMPOSER_GET_CLASS (operation);
-  GeglOperationClass         *op_class = GEGL_OPERATION_CLASS (klass);
   GeglBuffer                 *input;
   GeglBuffer                 *aux;
   GeglBuffer                 *output;
@@ -159,12 +158,9 @@ gegl_operation_composer_process (GeglOperation        *operation,
   if (input != NULL ||
       aux != NULL)
     {
-      gint threads = gegl_config ()->threads;
-
-      if (threads > 1 &&
-          op_class->parallelize &&
-          result->width * result->height > 64*64)
+      if (gegl_operation_use_threading (operation, result))
       {
+        gint threads = gegl_config ()->threads;
         GThreadPool *pool = thread_pool ();
         ThreadData thread_data[GEGL_MAX_THREADS];
         gint pending = threads;
diff --git a/gegl/operation/gegl-operation-composer3.c b/gegl/operation/gegl-operation-composer3.c
index b885661..523d265 100644
--- a/gegl/operation/gegl-operation-composer3.c
+++ b/gegl/operation/gegl-operation-composer3.c
@@ -195,9 +195,9 @@ gegl_operation_composer3_process (GeglOperation        *operation,
       aux != NULL ||
       aux2 != NULL)
     {
-      gint threads = gegl_config ()->threads;
-      if (threads > 1 && op_class->parallelize && result->width * result->height > 64*64)
+      if (gegl_operation_use_threading (operation, result))
       {
+        gint threads = gegl_config ()->threads;
         GThreadPool *pool = thread_pool ();
         ThreadData thread_data[GEGL_MAX_THREADS];
         gint pending = threads;
diff --git a/gegl/operation/gegl-operation-filter.c b/gegl/operation/gegl-operation-filter.c
index 680d02b..ede05b5 100644
--- a/gegl/operation/gegl-operation-filter.c
+++ b/gegl/operation/gegl-operation-filter.c
@@ -144,14 +144,11 @@ gegl_operation_filter_process (GeglOperation        *operation,
                                gint                  level)
 {
   GeglOperationFilterClass *klass;
-  GeglOperationClass       *op_class;
   GeglBuffer               *input;
   GeglBuffer               *output;
   gboolean                  success = FALSE;
-  gint threads = gegl_config ()->threads;
 
   klass = GEGL_OPERATION_FILTER_GET_CLASS (operation);
-  op_class = GEGL_OPERATION_CLASS (klass);
 
   g_assert (klass->process);
 
@@ -164,10 +161,9 @@ gegl_operation_filter_process (GeglOperation        *operation,
   input  = gegl_operation_context_get_source (context, "input");
   output = gegl_operation_context_get_target (context, "output");
 
-  if (threads > 1 && 
-      op_class->parallelize &&
-      result->width * result->height > 64*64)
+  if (gegl_operation_use_threading (operation, result))
   {
+    gint threads = gegl_config ()->threads;
     GThreadPool *pool = thread_pool ();
     ThreadData thread_data[GEGL_MAX_THREADS];
     gint pending = threads;
diff --git a/gegl/operation/gegl-operation-source.c b/gegl/operation/gegl-operation-source.c
index 233601a..1997eac 100644
--- a/gegl/operation/gegl-operation-source.c
+++ b/gegl/operation/gegl-operation-source.c
@@ -120,12 +120,8 @@ gegl_operation_source_process (GeglOperation        *operation,
                                gint                  level)
 {
   GeglOperationSourceClass *klass = GEGL_OPERATION_SOURCE_GET_CLASS (operation);
-  GeglOperationClass       *op_class;
   GeglBuffer               *output;
   gboolean                  success = FALSE;
-  gint threads = gegl_config ()->threads;
-
-  op_class = GEGL_OPERATION_CLASS (klass);
 
   if (strcmp (output_prop, "output"))
     {
@@ -136,10 +132,9 @@ gegl_operation_source_process (GeglOperation        *operation,
   g_assert (klass->process);
   output = gegl_operation_context_get_target (context, "output");
 
-  if (threads > 1 &&
-      op_class->parallelize &&
-      result->width * result->height > 64*64)
+  if (gegl_operation_use_threading (operation, result))
   {
+    gint threads = gegl_config ()->threads;
     GThreadPool *pool = thread_pool ();
     ThreadData thread_data[GEGL_MAX_THREADS];
     gint pending = threads;
diff --git a/gegl/operation/gegl-operation.c b/gegl/operation/gegl-operation.c
index 06c6bc7..3a72c83 100644
--- a/gegl/operation/gegl-operation.c
+++ b/gegl/operation/gegl-operation.c
@@ -23,6 +23,7 @@
 #include <string.h>
 
 #include "gegl.h"
+#include "gegl-config.h"
 #include "gegl-types-internal.h"
 #include "gegl-operation.h"
 #include "gegl-operation-context.h"
@@ -747,3 +748,26 @@ gegl_operation_get_source_format (GeglOperation *operation,
     }
   return NULL;
 }
+
+gboolean
+gegl_operation_use_threading (GeglOperation *operation,
+                              const GeglRectangle *roi)
+{
+  gint threads = gegl_config ()->threads;
+  if (threads == 1)
+    return FALSE;
+
+  {
+    GeglOperationClass       *op_class;
+    op_class = GEGL_OPERATION_GET_CLASS (operation);
+
+    if (op_class->opencl_support && gegl_cl_is_accelerated ())
+      return FALSE;
+
+    if (op_class->parallelize &&
+        roi->width * roi->height > 64*64)
+      return TRUE;
+  }
+  return FALSE;
+}
+
diff --git a/gegl/operation/gegl-operation.h b/gegl/operation/gegl-operation.h
index 02c6f72..07e4207 100644
--- a/gegl/operation/gegl-operation.h
+++ b/gegl/operation/gegl-operation.h
@@ -246,6 +246,10 @@ void          gegl_operation_set_key           (const gchar *operation_type,
 
 gboolean      gegl_operation_use_opencl         (const GeglOperation *operation);
 
+gboolean
+gegl_operation_use_threading (GeglOperation *operation,
+                              const GeglRectangle *roi);
+
 /* Invalidate a specific rectangle, indicating the any computation depending
  * on this roi is now invalid.
  *