Fine tune GPU burn library test

Author: Vasileios Karakasis

config/cscs.py

@@ -533,7 +533,6 @@
                     'descr': 'Tsa compute nodes',
                     'max_jobs': 20,
                     'features': ['gpu'],
-                    'extras': {'gpu_arch': 'sm_70'},
                     'resources': [
                         {
                             'name': '_rfm_gpu',

hpctestlib/microbenchmarks/gpu/gpu_burn.py

@@ -185,7 +185,7 @@ def set_num_gpus_per_node(self):
 
         gpu_devices = self.current_partition.select_devices('gpu')
         if gpu_devices:
-            self.num_gpus_per_node = len(gpu_devices)
+            self.num_gpus_per_node = gpu_devices[0].num_devices
 
     @sanity_function
     def assert_sanity(self):

reframe/core/systems.py

@@ -400,7 +400,7 @@ def features(self):
         '''
         return self._features
 
-    def select_devices(devtype):
+    def select_devices(self, devtype):
         '''Return all devices of the requested type:
 
         :arg devtype: The type of the device info objects to return.