backtrace.cpp

Go to the documentation of this file.

 
#include <cpu_io.h>
#include <elf.h>
 
#include <array>
#include <cstdint>
 
#include "arch.h"
#include "basic_info.hpp"
#include "kernel.h"
#include "kernel_elf.hpp"
#include "kernel_log.hpp"
 
__always_inline auto backtrace(std::array<uint64_t, kMaxFrameCount>& buffer)
    -> int {
  auto fp_value = cpu_io::Fp::Read();
  size_t count = 0;
 
  // RISC-V 栈帧布局 (使用 -fno-omit-frame-pointer):
  // fp[-1] (fp - 8):  保存的返回地址 (ra)
  // fp[-2] (fp - 16): 保存的上一个帧指针 (saved fp)
 
  while ((fp_value & 0x07) == 0 && count < buffer.max_size()) {
    auto* fp = reinterpret_cast<uint64_t*>(fp_value);
    auto ra = *(fp - 1);
    auto saved_fp = *(fp - 2);
 
    // 检查返回地址是否在代码段范围内
    if (ra < reinterpret_cast<uint64_t>(__executable_start) ||
        ra > reinterpret_cast<uint64_t>(__etext)) {
      break;
    }
 
    buffer[count++] = ra;
 
    // 如果 saved_fp 为 0 或无效，停止遍历
    if (saved_fp == 0) {
      break;
    }
    fp_value = saved_fp;
  }
  return static_cast<int>(count);
}
 
auto DumpStack() -> void {
  std::array<uint64_t, kMaxFrameCount> buffer{};
 
  // 获取调用栈中的地址
  auto num_frames = backtrace(buffer);
 
  // 打印函数名
  for (auto current_frame_idx = 0; current_frame_idx < num_frames;
       current_frame_idx++) {
    for (auto symtab : KernelElfSingleton::instance().symtab) {
      if ((ELF64_ST_TYPE(symtab.st_info) == STT_FUNC) &&
          (buffer[current_frame_idx] >= symtab.st_value) &&
          (buffer[current_frame_idx] <= symtab.st_value + symtab.st_size)) {
        klog::Err("[{}] {:#x}",
                  reinterpret_cast<const char*>(
                      KernelElfSingleton::instance().strtab + symtab.st_name),
                  buffer[current_frame_idx]);
      }
    }
  }
}