xref: /openbmc/qemu/scripts/qemugdb/mtree.py (revision 500016e5) 
1#!/usr/bin/python
2
3# GDB debugging support
4#
5# Copyright 2012 Red Hat, Inc. and/or its affiliates
6#
7# Authors:
8#  Avi Kivity <avi@redhat.com>
9#
10# This work is licensed under the terms of the GNU GPL, version 2 or
11# later.  See the COPYING file in the top-level directory.
12
13# 'qemu mtree' -- display the memory hierarchy
14
15import gdb
16
17def isnull(ptr):
18    return ptr == gdb.Value(0).cast(ptr.type)
19
20def int128(p):
21    '''Read an Int128 type to a python integer.
22
23    QEMU can be built with native Int128 support so we need to detect
24    if the value is a structure or the native type.
25    '''
26    if p.type.code == gdb.TYPE_CODE_STRUCT:
27        return int(p['lo']) + (int(p['hi']) << 64)
28    else:
29        return int(("%s" % p), 16)
30
31class MtreeCommand(gdb.Command):
32    '''Display the memory tree hierarchy'''
33    def __init__(self):
34        gdb.Command.__init__(self, 'qemu mtree', gdb.COMMAND_DATA,
35                             gdb.COMPLETE_NONE)
36        self.queue = []
37    def invoke(self, arg, from_tty):
38        self.seen = set()
39        self.queue_root('address_space_memory')
40        self.queue_root('address_space_io')
41        self.process_queue()
42    def queue_root(self, varname):
43        ptr = gdb.parse_and_eval(varname)['root']
44        self.queue.append(ptr)
45    def process_queue(self):
46        while self.queue:
47            ptr = self.queue.pop(0)
48            if int(ptr) in self.seen:
49                continue
50            self.print_item(ptr)
51    def print_item(self, ptr, offset = gdb.Value(0), level = 0):
52        self.seen.add(int(ptr))
53        addr = ptr['addr']
54        addr += offset
55        size = int128(ptr['size'])
56        alias = ptr['alias']
57        klass = ''
58        if not isnull(alias):
59            klass = ' (alias)'
60        elif not isnull(ptr['ops']):
61            klass = ' (I/O)'
62        elif bool(ptr['ram']):
63            klass = ' (RAM)'
64        gdb.write('%s%016x-%016x %s%s (@ %s)\n'
65                  % ('  ' * level,
66                     int(addr),
67                     int(addr + (size - 1)),
68                     ptr['name'].string(),
69                     klass,
70                     ptr,
71                     ),
72                  gdb.STDOUT)
73        if not isnull(alias):
74            gdb.write('%s    alias: %s@%016x (@ %s)\n' %
75                      ('  ' * level,
76                       alias['name'].string(),
77                       int(ptr['alias_offset']),
78                       alias,
79                       ),
80                      gdb.STDOUT)
81            self.queue.append(alias)
82        subregion = ptr['subregions']['tqh_first']
83        level += 1
84        while not isnull(subregion):
85            self.print_item(subregion, addr, level)
86            subregion = subregion['subregions_link']['tqe_next']
87
88