• qspinlock is a hybrid spinlock combining the fairness of ticket locks with the scalability of MCS locks: it uses only 4 bytes under low contention, falls back to an MCS queue under heavy load, and optimizes the second contender with a pending bit. It improves fairness and scalability but should not be enabled on RISC-V platforms lacking Ziccrse or Zabha.

• 使用hexo和GitHub Pagtes部署一个自己的博客

• How traps and system calls work on RISC-V. It introduces the trap mechanism, how user programs invoke system calls, how the kernel handles those traps, and how arguments are passed. It also covers kernel-mode traps, page faults, and real-world implications like protection and isolation.

• This chapter covers the fundamental concepts of paging hardware, memory allocation, and process address space management, including practical code implementations like creating address spaces, physical memory allocation, and process management functions such as sbrk and exec.

• This chapter2 explains how the OS is structured internally to manage hardware resources, run processes, and enforce protection.

• This chapter-1 introduces the basic Unix process, file, and I/O abstractions that applications use to interact with the OS.

File structure of xv6-riscv