1#!/usr/bin/python 2 3# GDB debugging support: aio/iohandler debug 4# 5# Copyright (c) 2015 Red Hat, Inc. 6# 7# Author: Dr. David Alan Gilbert <dgilbert@redhat.com> 8# 9# This work is licensed under the terms of the GNU GPL, version 2 or 10# later. See the COPYING file in the top-level directory. 11# 12 13import gdb 14from qemugdb import coroutine 15 16def isnull(ptr): 17 return ptr == gdb.Value(0).cast(ptr.type) 18 19def dump_aiocontext(context, verbose): 20 '''Display a dump and backtrace for an aiocontext''' 21 cur = context['aio_handlers']['lh_first'] 22 # Get pointers to functions we're going to process specially 23 sym_fd_coroutine_enter = gdb.parse_and_eval('fd_coroutine_enter') 24 25 while not isnull(cur): 26 entry = cur.dereference() 27 gdb.write('----\n%s\n' % entry) 28 if verbose and cur['io_read'] == sym_fd_coroutine_enter: 29 coptr = (cur['opaque'].cast(gdb.lookup_type('FDYieldUntilData').pointer()))['co'] 30 coptr = coptr.cast(gdb.lookup_type('CoroutineUContext').pointer()) 31 coroutine.bt_jmpbuf(coptr['env']['__jmpbuf']) 32 cur = cur['node']['le_next']; 33 34 gdb.write('----\n') 35 36class HandlersCommand(gdb.Command): 37 '''Display aio handlers''' 38 def __init__(self): 39 gdb.Command.__init__(self, 'qemu handlers', gdb.COMMAND_DATA, 40 gdb.COMPLETE_NONE) 41 42 def invoke(self, arg, from_tty): 43 verbose = False 44 argv = gdb.string_to_argv(arg) 45 46 if len(argv) > 0 and argv[0] == '--verbose': 47 verbose = True 48 argv.pop(0) 49 50 if len(argv) > 1: 51 gdb.write('usage: qemu handlers [--verbose] [handler]\n') 52 return 53 54 if len(argv) == 1: 55 handlers_name = argv[0] 56 else: 57 handlers_name = 'qemu_aio_context' 58 dump_aiocontext(gdb.parse_and_eval(handlers_name), verbose) 59