solver: avoid reinitializing action in cpr/selfcons

usadelndsoc/solver.py

@@ -75,7 +75,11 @@ def _norm(z):
 
 
 class Solver:
+    __global_id = 0
+
     def __init__(self, nx=1, ny=1):
+        Solver.__global_id += 1
+        self._id = Solver.__global_id
         self._core = Core()
         self.set_shape(nx, ny)
         self._M = None
@@ -901,9 +905,25 @@ def _self_consistent_Delta_f(
     return rtot, Jtot, mask
 
 
+_prev_solver = None
+
+
 def _mp_one(args, solver=None, solver_kw=None):
+    global _prev_solver
+
     w, a, solver, solver_kw = args
 
+    if (
+        _prev_solver is not None
+        and _prev_solver is not solver
+        and solver._id == _prev_solver._id
+    ):
+        # Only dynamic variables may have changed
+        _prev_solver.Omega[...] = solver.Omega
+        solver = _prev_solver
+    else:
+        _prev_solver = solver
+
     old_level = _log_solve.level
     try:
         _log_solve.setLevel(_log.getEffectiveLevel() + 10)