scripts/qemugdb/mtree.py

   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
  15 import gdb
  16
  17 def isnull(ptr):
  18     return ptr == gdb.Value(0).cast(ptr.type)
  19
  20 def 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
  31 class 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