RJMM: Real-time Enhancement for Jailhouse Hypervisor on Multi-Core Platforms via Memory Isolation

Abstract

With the improvement in computing power provided by modern multi-core architectures, software developers tend to integrate hybrid key systems into a single multi-core hardware platform to reduce costs. When integrating hybrid critical systems into a multi-core platform, critical tasks should not be affected by non critical tasks, so isolating shared resources between different critical levels is a major challenge. As virtualization technology can provide complete isolation of hardware shared resources, in this paper, a mechanism that prevents the DRAM bank interference from non real-time cell and hypervisor to real-time cell on multi-core platforms via bank partitioning to enhance real-time for the Jailhouse hypervisor is proposed. Based on that mechanism, the memory access of non real-time cell and Jailhouse hypervisor will not cause DRAM bank interference to all real-time tasks which run in the real-time cell and are limited to accessing the physical pages belonging to the DRAM bank assigned to the real-time cell. A series of experiments are performed on the Raspberry Pi 4 show that RJMM is effective in improving the real-time and isolation performance composed of the native Jailhouse.