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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-17 14:35:02 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-17 14:35:02 -0800 |
| commit | e2b74f232e84dfccd0047eb47545b1d028df8ff1 (patch) | |
| tree | 86dffe011c9b4049f2adfa7aa78ad92870c4dc9b /scripts/gdb/linux/utils.py | |
| parent | 9cd77374f0a9cbb7ec35a9aaeb6473755afe0e3e (diff) | |
| parent | 580c57f1076872ebc2427f898b927944ce170f2d (diff) | |
| download | lwn-e2b74f232e84dfccd0047eb47545b1d028df8ff1.tar.gz lwn-e2b74f232e84dfccd0047eb47545b1d028df8ff1.zip | |
Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:
- a pile of minor fs fixes and cleanups
- kexec updates
- random misc fixes in various places: vmcore, rbtree, eventfd, ipc, seccomp.
- a series of python-based kgdb helper scripts
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (58 commits)
seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO
samples/seccomp: improve label helper
ipc,sem: use current->state helpers
scripts/gdb: disable pagination while printing from breakpoint handler
scripts/gdb: define maintainer
scripts/gdb: convert CpuList to generator function
scripts/gdb: convert ModuleList to generator function
scripts/gdb: use a generator instead of iterator for task list
scripts/gdb: ignore byte-compiled python files
scripts/gdb: port to python3 / gdb7.7
scripts/gdb: add basic documentation
scripts/gdb: add lx-lsmod command
scripts/gdb: add class to iterate over CPU masks
scripts/gdb: add lx_current convenience function
scripts/gdb: add internal helper and convenience function for per-cpu lookup
scripts/gdb: add get_gdbserver_type helper
scripts/gdb: add internal helper and convenience function to retrieve thread_info
scripts/gdb: add is_target_arch helper
scripts/gdb: add helper and convenience function to look up tasks
scripts/gdb: add task iteration class
...
Diffstat (limited to 'scripts/gdb/linux/utils.py')
| -rw-r--r-- | scripts/gdb/linux/utils.py | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/scripts/gdb/linux/utils.py b/scripts/gdb/linux/utils.py new file mode 100644 index 000000000000..128c306db3ee --- /dev/null +++ b/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 |