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-rw-r--r--kernel/scripts/gdb/linux/utils.py156
1 files changed, 156 insertions, 0 deletions
diff --git a/kernel/scripts/gdb/linux/utils.py b/kernel/scripts/gdb/linux/utils.py
new file mode 100644
index 000000000..128c306db
--- /dev/null
+++ b/kernel/scripts/gdb/linux/utils.py
@@ -0,0 +1,156 @@
+#
+# gdb helper commands and functions for Linux kernel debugging
+#
+# common utilities
+#
+# Copyright (c) Siemens AG, 2011-2013
+#
+# Authors:
+# Jan Kiszka <jan.kiszka@siemens.com>
+#
+# This work is licensed under the terms of the GNU GPL version 2.
+#
+
+import gdb
+
+
+class CachedType:
+ def __init__(self, name):
+ self._type = None
+ self._name = name
+
+ def _new_objfile_handler(self, event):
+ self._type = None
+ gdb.events.new_objfile.disconnect(self._new_objfile_handler)
+
+ def get_type(self):
+ if self._type is None:
+ self._type = gdb.lookup_type(self._name)
+ if self._type is None:
+ raise gdb.GdbError(
+ "cannot resolve type '{0}'".format(self._name))
+ if hasattr(gdb, 'events') and hasattr(gdb.events, 'new_objfile'):
+ gdb.events.new_objfile.connect(self._new_objfile_handler)
+ return self._type
+
+
+long_type = CachedType("long")
+
+
+def get_long_type():
+ global long_type
+ return long_type.get_type()
+
+
+def offset_of(typeobj, field):
+ element = gdb.Value(0).cast(typeobj)
+ return int(str(element[field].address).split()[0], 16)
+
+
+def container_of(ptr, typeobj, member):
+ return (ptr.cast(get_long_type()) -
+ offset_of(typeobj, member)).cast(typeobj)
+
+
+class ContainerOf(gdb.Function):
+ """Return pointer to containing data structure.
+
+$container_of(PTR, "TYPE", "ELEMENT"): Given PTR, return a pointer to the
+data structure of the type TYPE in which PTR is the address of ELEMENT.
+Note that TYPE and ELEMENT have to be quoted as strings."""
+
+ def __init__(self):
+ super(ContainerOf, self).__init__("container_of")
+
+ def invoke(self, ptr, typename, elementname):
+ return container_of(ptr, gdb.lookup_type(typename.string()).pointer(),
+ elementname.string())
+
+ContainerOf()
+
+
+BIG_ENDIAN = 0
+LITTLE_ENDIAN = 1
+target_endianness = None
+
+
+def get_target_endianness():
+ global target_endianness
+ if target_endianness is None:
+ endian = gdb.execute("show endian", to_string=True)
+ if "little endian" in endian:
+ target_endianness = LITTLE_ENDIAN
+ elif "big endian" in endian:
+ target_endianness = BIG_ENDIAN
+ else:
+ raise gdb.GdgError("unknown endianness '{0}'".format(str(endian)))
+ return target_endianness
+
+
+def read_u16(buffer):
+ if get_target_endianness() == LITTLE_ENDIAN:
+ return ord(buffer[0]) + (ord(buffer[1]) << 8)
+ else:
+ return ord(buffer[1]) + (ord(buffer[0]) << 8)
+
+
+def read_u32(buffer):
+ if get_target_endianness() == LITTLE_ENDIAN:
+ return read_u16(buffer[0:2]) + (read_u16(buffer[2:4]) << 16)
+ else:
+ return read_u16(buffer[2:4]) + (read_u16(buffer[0:2]) << 16)
+
+
+def read_u64(buffer):
+ if get_target_endianness() == LITTLE_ENDIAN:
+ return read_u32(buffer[0:4]) + (read_u32(buffer[4:8]) << 32)
+ else:
+ return read_u32(buffer[4:8]) + (read_u32(buffer[0:4]) << 32)
+
+
+target_arch = None
+
+
+def is_target_arch(arch):
+ if hasattr(gdb.Frame, 'architecture'):
+ return arch in gdb.newest_frame().architecture().name()
+ else:
+ global target_arch
+ if target_arch is None:
+ target_arch = gdb.execute("show architecture", to_string=True)
+ return arch in target_arch
+
+
+GDBSERVER_QEMU = 0
+GDBSERVER_KGDB = 1
+gdbserver_type = None
+
+
+def get_gdbserver_type():
+ def exit_handler(event):
+ global gdbserver_type
+ gdbserver_type = None
+ gdb.events.exited.disconnect(exit_handler)
+
+ def probe_qemu():
+ try:
+ return gdb.execute("monitor info version", to_string=True) != ""
+ except:
+ return False
+
+ def probe_kgdb():
+ try:
+ thread_info = gdb.execute("info thread 2", to_string=True)
+ return "shadowCPU0" in thread_info
+ except:
+ return False
+
+ global gdbserver_type
+ if gdbserver_type is None:
+ if probe_qemu():
+ gdbserver_type = GDBSERVER_QEMU
+ elif probe_kgdb():
+ gdbserver_type = GDBSERVER_KGDB
+ if not gdbserver_type is None and hasattr(gdb, 'events'):
+ gdb.events.exited.connect(exit_handler)
+ return gdbserver_type