Computing systems are becoming more and more dynamically reconfigurable or adaptive, to be flexible w.r.t. their environment and to automate their administration. Autonomic computing proposes a general structure of feedback loop to take this into account. In this report, we are particularly interested in approaches where this feedback loop is considered as a case of control loop where techniques stemming from Control Theory can be used to design efficient safe, and predictable controllers. This approach is emerging, with separate and dispersed effort, in different areas of the field of reconfigurable or adaptive computing, at software or architecture level. This report surveys these approaches from the point of view of control theory techniques, continuous and discrete, in their application to the feedback control of computing systems, and proposes interpretations of feedback control loops as MAPE-K loop, illustrated with case studies.