[gegl] gegl: limit default _gegl_threads to GEGL_MAX_THREADS

[Øyvind Kolås <ok src gnome org>]

commit d305ddb1e8a75f346c0515542c937fd3699ecef1
Author: Øyvind Kolås <pippin gimp org>
Date:   Tue May 22 12:06:53 2018 +0200

    gegl: limit default _gegl_threads to GEGL_MAX_THREADS
    
    On systems with many cores this limit already triggers, as in
    bug #796289.

 gegl/gegl-config.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gegl/gegl-config.c b/gegl/gegl-config.c
index c25ee64..9f8f964 100644
--- a/gegl/gegl-config.c
+++ b/gegl/gegl-config.c
@@ -225,7 +225,8 @@ gegl_config_class_init (GeglConfigClass *klass)
                                                         G_PARAM_READWRITE |
                                                         G_PARAM_CONSTRUCT));
 
-  _gegl_threads = g_get_num_processors ();
+  _gegl_threads = MAX (GEGL_MAX_THREADS, g_get_num_processors ());
+
   g_object_class_install_property (gobject_class, PROP_THREADS,
                                    g_param_spec_int ("threads",
                                                      "Number of threads",