    def put(self, key, dat):
      """
      Warning: This function blocks until the param is written to disk!
      In very rare cases this can take over a second, and your code will hang.
      Use the put_nonblocking, put_bool_nonblocking in time sensitive code, but
      in general try to avoid writing params as much as possible.
      """
      cdef string k = self.check_key(key)
      cdef string dat_bytes = ensure_bytes(dat)
      with nogil:
 
</s> remove   def put_nonblocking(self, key, dat):
    cdef string k = self.check_key(key)
    cdef string dat_bytes = ensure_bytes(dat)
    with nogil:
      self.p.putNonBlocking(k, dat_bytes)

  def put_bool_nonblocking(self, key, bool val):
    cdef string k = self.check_key(key)
    with nogil:
      self.p.putBoolNonBlocking(k, val)

 </s> add  </s> remove         self.params.put_nonblocking("CarBatteryCapacity", str(int(self.car_battery_capacity_uWh)))
 </s> add         put_nonblocking("CarBatteryCapacity", str(int(self.car_battery_capacity_uWh))) </s> remove from openpilot.common.params import Params, ParamKeyType, UnknownKeyName
 </s> add from openpilot.common.params import Params, ParamKeyType, UnknownKeyName, put_nonblocking, put_bool_nonblocking </s> remove   params = Params()

 </s> add 
    Use the put_nonblocking helper function in time sensitive code, but
    def put(self, key, dat):
      """
      Warning: This function blocks until the param is written to disk!
      In very rare cases this can take over a second, and your code will hang.
    Use the put_nonblocking helper function in time sensitive code, but
      in general try to avoid writing params as much as possible.
      """
      cdef string k = self.check_key(key)
      cdef string dat_bytes = ensure_bytes(dat)
      with nogil:
keep keep keep keep replace keep keep keep keep keep
 Revert "params: safe and efficient async writing parameters (#25912)"

This reverts commit 0d797f4e8b2552192669d0329c14849f0a970066. 
common/params_pyx.pyx