SPMVisor: Dynamic scratchpad memory virtualization for secure, low power, and high performance distributed on-chip memories

Emerging multicore platforms are increasingly deploying distributed scratchpad memories to achieve lower energy and area together with higher predictability; but this requires transparent and efficient software management of these critical resources. In this paper, we introduce SPMVisor, a hardware/software layer that virtualizes the scratchpad memory space in order to facilitate the use of distributed SPMs in an efficient, transparent and secure manner. We introduce the notion of virtual scratchpad memories (vSPMs), which can be dynamically created and managed as regular SPMs. To protect the on-chip memory space, the SP-MVisor supports vSPM-level and block-level access control lists. In order to efficiently manage the on-chip real-estate, our SPMVisor supports policy-driven allocation strategies based on privilege levels. Our experimental results on Me-diabench/CHStone benchmarks running on various Chip-Multiprocessor configurations and software stacks (RTOS, virtualization, secure execution) show that SPMVisor enhances performance by 71% on average and reduces power consumption by 79% on average.