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.  See
  11 # the COPYING file in the top-level directory.
  12 #
  13 # Contributions after 2012-01-13 are licensed under the terms of the
  14 # GNU GPL, version 2 or (at your option) any later version.
  15
  16 # 'qemu mtree' -- display the memory hierarchy
  17
  18 import gdb
  19
  20 def isnull(ptr):
  21     return ptr == gdb.Value(0).cast(ptr.type)
  22
  23 def int128(p):
  24     '''Read an Int128 type to a python integer.
  25
  26     QEMU can be built with native Int128 support so we need to detect
  27     if the value is a structure or the native type.
  28     '''
  29     if p.type.code == gdb.TYPE_CODE_STRUCT:
  30         return int(p['lo']) + (int(p['hi']) << 64)
  31     else:
  32         return int(("%s" % p), 16)
  33
  34 class MtreeCommand(gdb.Command):
  35     '''Display the memory tree hierarchy'''
  36     def __init__(self):
  37         gdb.Command.__init__(self, 'qemu mtree', gdb.COMMAND_DATA,
  38                              gdb.COMPLETE_NONE)
  39         self.queue = []
  40     def invoke(self, arg, from_tty):
  41         self.seen = set()
  42         self.queue_root('address_space_memory')
  43         self.queue_root('address_space_io')
  44         self.process_queue()
  45     def queue_root(self, varname):
  46         ptr = gdb.parse_and_eval(varname)['root']
  47         self.queue.append(ptr)
  48     def process_queue(self):
  49         while self.queue:
  50             ptr = self.queue.pop(0)
  51             if int(ptr) in self.seen:
  52                 continue
  53             self.print_item(ptr)
  54     def print_item(self, ptr, offset = gdb.Value(0), level = 0):
  55         self.seen.add(int(ptr))
  56         addr = ptr['addr']
  57         addr += offset
  58         size = int128(ptr['size'])
  59         alias = ptr['alias']
  60         klass = ''
  61         if not isnull(alias):
  62             klass = ' (alias)'
  63         elif not isnull(ptr['ops']):
  64             klass = ' (I/O)'
  65         elif bool(ptr['ram']):
  66             klass = ' (RAM)'
  67         gdb.write('%s%016x-%016x %s%s (@ %s)\n'
  68                   % ('  ' * level,
  69                      int(addr),
  70                      int(addr + (size - 1)),
  71                      ptr['name'].string(),
  72                      klass,
  73                      ptr,
  74                      ),
  75                   gdb.STDOUT)
  76         if not isnull(alias):
  77             gdb.write('%s    alias: %s@%016x (@ %s)\n' %
  78                       ('  ' * level,
  79                        alias['name'].string(),
  80                        int(ptr['alias_offset']),
  81                        alias,
  82                        ),
  83                       gdb.STDOUT)
  84             self.queue.append(alias)
  85         subregion = ptr['subregions']['tqh_first']
  86         level += 1
  87         while not isnull(subregion):
  88             self.print_item(subregion, addr, level)
  89             subregion = subregion['subregions_link']['tqe_next']
  90