The progressive demand for distributed multimedia applications, which are characterized by strong requirements over computational resources, makes evident the need for quality of service (QoS) provisioning in each one of the involved subsystems (e.g. communication networks and operating systems). At the same time, these subsystems must be flexible enough that they can offer new services to future applications, or in other words, they must be adaptable at runtime. Specifically, general-purpose operating systems provide few or no QoS/service adaptability support, what have motivated many isolated studies about these topics. Observing some implemented technologies on specific operating systems,it is noted that the provisioning mechanisms have certain functional similarities.In this way, this work proposes an adaptable architecture for QoS provisioning on networking and process scheduling subsystems of operating systems, through the description of generic frameworks. It is demonstrated how the framework hot-spots can be specialized in order to implement some QoS models. Finally, it is proposed a scenario of use of the architecture, where a bit modified generalpurpose operating system is used as infrastructure for an instantiation of the QoS frameworks.