OpenCloudOS-Kernel/scripts/gdb/linux/dmesg.py

66 lines
2.0 KiB
Python

#
# gdb helper commands and functions for Linux kernel debugging
#
# kernel log buffer dump
#
# Copyright (c) Siemens AG, 2011, 2012
#
# Authors:
# Jan Kiszka <jan.kiszka@siemens.com>
#
# This work is licensed under the terms of the GNU GPL version 2.
#
import gdb
from linux import utils
class LxDmesg(gdb.Command):
"""Print Linux kernel log buffer."""
def __init__(self):
super(LxDmesg, self).__init__("lx-dmesg", gdb.COMMAND_DATA)
def invoke(self, arg, from_tty):
log_buf_addr = int(str(gdb.parse_and_eval("log_buf")).split()[0], 16)
log_first_idx = int(gdb.parse_and_eval("log_first_idx"))
log_next_idx = int(gdb.parse_and_eval("log_next_idx"))
log_buf_len = int(gdb.parse_and_eval("log_buf_len"))
inf = gdb.inferiors()[0]
start = log_buf_addr + log_first_idx
if log_first_idx < log_next_idx:
log_buf_2nd_half = -1
length = log_next_idx - log_first_idx
log_buf = utils.read_memoryview(inf, start, length).tobytes()
else:
log_buf_2nd_half = log_buf_len - log_first_idx
a = utils.read_memoryview(inf, start, log_buf_2nd_half)
b = utils.read_memoryview(inf, log_buf_addr, log_next_idx)
log_buf = a.tobytes() + b.tobytes()
pos = 0
while pos < log_buf.__len__():
length = utils.read_u16(log_buf[pos + 8:pos + 10])
if length == 0:
if log_buf_2nd_half == -1:
gdb.write("Corrupted log buffer!\n")
break
pos = log_buf_2nd_half
continue
text_len = utils.read_u16(log_buf[pos + 10:pos + 12])
text = log_buf[pos + 16:pos + 16 + text_len].decode()
time_stamp = utils.read_u64(log_buf[pos:pos + 8])
for line in text.splitlines():
gdb.write("[{time:12.6f}] {line}\n".format(
time=time_stamp / 1000000000.0,
line=line))
pos += length
LxDmesg()