scripts/qemu-gdb: Split MtreeCommand into its own module

As we add more commands to our Python gdb debugging support, it's
going to get unwieldy to have everything in a single file. Split
the implementation of the 'mtree' command from qemu-gdb.py into
its own module.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1439574392-4403-2-git-send-email-peter.maydell@linaro.org

3 files changed, 118 insertions, 62 deletions

diff --git a/scripts/qemu-gdb.py b/scripts/qemu-gdb.py
index 6c7f4fb..7b072ad 100644
--- a/scripts/qemu-gdb.py
+++ b/scripts/qemu-gdb.py
@@ -16,11 +16,14 @@
 
 import gdb
 
-def isnull(ptr):
-    return ptr == gdb.Value(0).cast(ptr.type)
+import os, sys
 
-def int128(p):
-    return long(p['lo']) + (long(p['hi']) << 64)
+# Annoyingly, gdb doesn't put the directory of scripts onto the
+# module search path. Do it manually.
+
+sys.path.append(os.path.dirname(__file__))
+
+from qemugdb import mtree
 
 def get_fs_base():
     '''Fetch %fs base value using arch_prctl(ARCH_GET_FS)'''
@@ -102,63 +105,6 @@ class CoroutineCommand(gdb.Command):
         coroutine_pointer = gdb.parse_and_eval(argv[0]).cast(gdb.lookup_type('CoroutineUContext').pointer())
         bt_jmpbuf(coroutine_pointer['env']['__jmpbuf'])
 
-class MtreeCommand(gdb.Command):
-    '''Display the memory tree hierarchy'''
-    def __init__(self):
-        gdb.Command.__init__(self, 'qemu mtree', gdb.COMMAND_DATA,
-                             gdb.COMPLETE_NONE)
-        self.queue = []
-    def invoke(self, arg, from_tty):
-        self.seen = set()
-        self.queue_root('address_space_memory')
-        self.queue_root('address_space_io')
-        self.process_queue()
-    def queue_root(self, varname):
-        ptr = gdb.parse_and_eval(varname)['root']
-        self.queue.append(ptr)
-    def process_queue(self):
-        while self.queue:
-            ptr = self.queue.pop(0)
-            if long(ptr) in self.seen:
-                continue
-            self.print_item(ptr)
-    def print_item(self, ptr, offset = gdb.Value(0), level = 0):
-        self.seen.add(long(ptr))
-        addr = ptr['addr']
-        addr += offset
-        size = int128(ptr['size'])
-        alias = ptr['alias']
-        klass = ''
-        if not isnull(alias):
-            klass = ' (alias)'
-        elif not isnull(ptr['ops']):
-            klass = ' (I/O)'
-        elif bool(ptr['ram']):
-            klass = ' (RAM)'
-        gdb.write('%s%016x-%016x %s%s (@ %s)\n'
-                  % ('  ' * level,
-                     long(addr),
-                     long(addr + (size - 1)),
-                     ptr['name'].string(),
-                     klass,
-                     ptr,
-                     ),
-                  gdb.STDOUT)
-        if not isnull(alias):
-            gdb.write('%s    alias: %s@%016x (@ %s)\n' %
-                      ('  ' * level,
-                       alias['name'].string(),
-                       ptr['alias_offset'],
-                       alias,
-                       ),
-                      gdb.STDOUT)
-            self.queue.append(alias)
-        subregion = ptr['subregions']['tqh_first']
-        level += 1
-        while not isnull(subregion):
-            self.print_item(subregion, addr, level)
-            subregion = subregion['subregions_link']['tqe_next']
-
 QemuCommand()
 CoroutineCommand()
-MtreeCommand()
+mtree.MtreeCommand()
diff --git a/scripts/qemugdb/__init__.py b/scripts/qemugdb/__init__.py
new file mode 100644
index 0000000..969f552
--- /dev/null
+++ b/scripts/qemugdb/__init__.py
@@ -0,0 +1,28 @@
+#!/usr/bin/python
+
+# GDB debugging support
+#
+# Copyright (c) 2015 Linaro Ltd
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, see
+# <http://www.gnu.org/licenses/gpl-2.0.html>
+#
+
+# We don't need to do anything in our init file currently.
+
+"""
+Support routines for debugging QEMU under GDB
+"""
+
+__license__    = "GPL version 2 or (at your option) any later version"
diff --git a/scripts/qemugdb/mtree.py b/scripts/qemugdb/mtree.py
new file mode 100644
index 0000000..06011c3
--- /dev/null
+++ b/scripts/qemugdb/mtree.py
@@ -0,0 +1,82 @@
+#!/usr/bin/python
+
+# GDB debugging support
+#
+# Copyright 2012 Red Hat, Inc. and/or its affiliates
+#
+# Authors:
+#  Avi Kivity <avi@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2.  See
+# the COPYING file in the top-level directory.
+#
+# Contributions after 2012-01-13 are licensed under the terms of the
+# GNU GPL, version 2 or (at your option) any later version.
+
+# 'qemu mtree' -- display the memory hierarchy
+
+import gdb
+
+def isnull(ptr):
+    return ptr == gdb.Value(0).cast(ptr.type)
+
+def int128(p):
+    return long(p['lo']) + (long(p['hi']) << 64)
+
+class MtreeCommand(gdb.Command):
+    '''Display the memory tree hierarchy'''
+    def __init__(self):
+        gdb.Command.__init__(self, 'qemu mtree', gdb.COMMAND_DATA,
+                             gdb.COMPLETE_NONE)
+        self.queue = []
+    def invoke(self, arg, from_tty):
+        self.seen = set()
+        self.queue_root('address_space_memory')
+        self.queue_root('address_space_io')
+        self.process_queue()
+    def queue_root(self, varname):
+        ptr = gdb.parse_and_eval(varname)['root']
+        self.queue.append(ptr)
+    def process_queue(self):
+        while self.queue:
+            ptr = self.queue.pop(0)
+            if long(ptr) in self.seen:
+                continue
+            self.print_item(ptr)
+    def print_item(self, ptr, offset = gdb.Value(0), level = 0):
+        self.seen.add(long(ptr))
+        addr = ptr['addr']
+        addr += offset
+        size = int128(ptr['size'])
+        alias = ptr['alias']
+        klass = ''
+        if not isnull(alias):
+            klass = ' (alias)'
+        elif not isnull(ptr['ops']):
+            klass = ' (I/O)'
+        elif bool(ptr['ram']):
+            klass = ' (RAM)'
+        gdb.write('%s%016x-%016x %s%s (@ %s)\n'
+                  % ('  ' * level,
+                     long(addr),
+                     long(addr + (size - 1)),
+                     ptr['name'].string(),
+                     klass,
+                     ptr,
+                     ),
+                  gdb.STDOUT)
+        if not isnull(alias):
+            gdb.write('%s    alias: %s@%016x (@ %s)\n' %
+                      ('  ' * level,
+                       alias['name'].string(),
+                       ptr['alias_offset'],
+                       alias,
+                       ),
+                      gdb.STDOUT)
+            self.queue.append(alias)
+        subregion = ptr['subregions']['tqh_first']
+        level += 1
+        while not isnull(subregion):
+            self.print_item(subregion, addr, level)
+            subregion = subregion['subregions_link']['tqe_next']
+