PendSV Allows Simple and Efficient Context Switch on Cortex-M
Centralizing context switch logic in PendSV simplifies concurrency reasoning and enhances system performance by reducing register preservation overhead of all other exceptions.
Zhiyao Ma
Ph.D Candidate
Yale University
About Me
Zhiyao Ma is a Ph.D candidate in the department of computer science at Yale University. He is advised by Professor Lin Zhong, Ph.D. His research interests lie in the field of operating systems on resource constrained platforms, programming languages, and automated code generation via large language models. Zhiyao’s current focus is on building a Rust-based embedded operating system called Hopter, which enables memory safe, memory efficient, reliable, and responsive applications via a co-design between the kernel and compiler. His future work will explore the opportunity to expedite system development facilitated by large language models, and to empower a resource constrained computer at the OS layer aided by a resourceful computer connected over the network. Zhiyao enjoys driving on tracks at HPDE, currently in the intermediate run group, and he also holds a Kendo 3rd Dan rank.
Interests
- Operating System
- Embedded System
- Programming Language
- Automated Code Generation
Education
-
Ph.D Student in Computer Science, 2020 - Present
Yale University
-
MPhil in Computer Science, 2024
Yale University
-
MS in Computer Science, 2023
Yale University
-
BS in Computer Science (Summa Cum Laude), 2020
Peking University
Recent Posts
Changing Rust Enum Variant with Mutable Reference
Changing a Rust enum variant through a mutable reference can be achieved either by wrapping the variant attached variable inside Option, or better, by introducing an Undef variant in the enum.
Rust Crate Crossbeam's ArrayQueue Can Deadlock
Although ArrayQueue contains no explicit spin lock or mutex, its code structure forms a big spin lock and thus deadlock is possible.
SVC Can Be Invoked Asynchronously When Dynamically Changing Exception Priority on Cortex-M
SVC will be pended if a higher priority exception arrives during the stacking. If the priority of SVC is raised above the previously higher priority exception inside its handler, SVC will be activated immediately, nested above the current handler, which causes problems because the register context seen by the SVC handler is not system call arguments.
Read-Modify-Write On Self-Changing Registers Causes Trouble
Read-modify-write on the cr1 register of I²C may generate two consecutive start condition and hang the peripheral.
Recent Publications
(2024).
Offloading Operating System Functions to the Cloud.
In HotMobile 2024.
(2023).
Panic Recovery in Rust-based Embedded Systems.
In PLOS 2023.
(2023).
POLYCORN: Data-driven Cross-layer Multipath Networking for High-speed Railway through Composable Schedulerlets.
In NSDI 2023.
(2023).
Bringing Segmented Stacks to Embedded Systems.
In HotMobile 2023.
(2020).
SCYLLA: QoE-aware Continuous Mobile Vision with FPGA-based Dynamic Deep Neural Network Reconfiguration.
In INFOCOM 2020.