force 1 thread is eddy run on gpu

Author: mauriliogenovese

Diff for: nipype/interfaces/fsl/epi.py

@@ -960,6 +960,8 @@ def __init__(self, **inputs):
             self._use_cuda()
 
     def _num_threads_update(self):
+        if self.inputs.use_cuda and gpu_count()>0:
+            self.inputs.num_threads = 1
         self._num_threads = self.inputs.num_threads
         if not isdefined(self.inputs.num_threads):
             if "OMP_NUM_THREADS" in self.inputs.environ:
@@ -969,6 +971,7 @@ def _num_threads_update(self):
 
     def _use_cuda(self):
         if self.inputs.use_cuda and gpu_count()>0:
+            self.inputs.num_threads = 1
             # eddy_cuda usually link to eddy_cudaX.X but some versions miss the symlink
             # anyway in newer fsl versions eddy automatically use cuda on cuda-capable systems
             self._cmd = "eddy_cuda" if which("eddy_cuda") else "eddy"