Module os::trap

Trap handling functionality

For rCore, we have a single trap entry point, namely __alltraps. At initialization in init(), we set the stvec CSR to point to it.

All traps go through __alltraps, which is defined in trap.S. The assembly language code does just enough work restore the kernel space context, ensuring that Rust code safely runs, and transfers control to trap_handler().

It then calls different functionality based on what exactly the exception was. For example, timer interrupts trigger task preemption, and syscalls go to syscall().

Modules

• context 🔒

Structs

• TrapContext
  Trap Context

Functions

• init
  initialize CSR stvec as the entry of __alltraps
• trap_handler
  handle an interrupt, exception, or system call from user space