Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1#
2# gdb helper commands and functions for Linux kernel debugging
3#
4# task & thread tools
5#
6# Copyright (c) Siemens AG, 2011-2013
7#
8# Authors:
9# Jan Kiszka <jan.kiszka@siemens.com>
10#
11# This work is licensed under the terms of the GNU GPL version 2.
12#
13
14import gdb
15
16from linux import utils, lists
17
18
19task_type = utils.CachedType("struct task_struct")
20
21
22def task_lists():
23 task_ptr_type = task_type.get_type().pointer()
24 init_task = gdb.parse_and_eval("init_task").address
25 t = init_task
26
27 while True:
28 thread_head = t['signal']['thread_head']
29 for thread in lists.list_for_each_entry(thread_head, task_ptr_type, 'thread_node'):
30 yield thread
31
32 t = utils.container_of(t['tasks']['next'],
33 task_ptr_type, "tasks")
34 if t == init_task:
35 return
36
37
38def get_task_by_pid(pid):
39 for task in task_lists():
40 if int(task['pid']) == pid:
41 return task
42 return None
43
44
45class LxTaskByPidFunc(gdb.Function):
46 """Find Linux task by PID and return the task_struct variable.
47
48$lx_task_by_pid(PID): Given PID, iterate over all tasks of the target and
49return that task_struct variable which PID matches."""
50
51 def __init__(self):
52 super(LxTaskByPidFunc, self).__init__("lx_task_by_pid")
53
54 def invoke(self, pid):
55 task = get_task_by_pid(pid)
56 if task:
57 return task.dereference()
58 else:
59 raise gdb.GdbError("No task of PID " + str(pid))
60
61
62LxTaskByPidFunc()
63
64
65class LxPs(gdb.Command):
66 """Dump Linux tasks."""
67
68 def __init__(self):
69 super(LxPs, self).__init__("lx-ps", gdb.COMMAND_DATA)
70
71 def invoke(self, arg, from_tty):
72 gdb.write("{:>10} {:>12} {:>7}\n".format("TASK", "PID", "COMM"))
73 for task in task_lists():
74 gdb.write("{} {:^5} {}\n".format(
75 task.format_string().split()[0],
76 task["pid"].format_string(),
77 task["comm"].string()))
78
79
80LxPs()
81
82
83thread_info_type = utils.CachedType("struct thread_info")
84
85ia64_task_size = None
86
87
88def get_thread_info(task):
89 thread_info_ptr_type = thread_info_type.get_type().pointer()
90 if utils.is_target_arch("ia64"):
91 global ia64_task_size
92 if ia64_task_size is None:
93 ia64_task_size = gdb.parse_and_eval("sizeof(struct task_struct)")
94 thread_info_addr = task.address + ia64_task_size
95 thread_info = thread_info_addr.cast(thread_info_ptr_type)
96 else:
97 if task.type.fields()[0].type == thread_info_type.get_type():
98 return task['thread_info']
99 thread_info = task['stack'].cast(thread_info_ptr_type)
100 return thread_info.dereference()
101
102
103class LxThreadInfoFunc (gdb.Function):
104 """Calculate Linux thread_info from task variable.
105
106$lx_thread_info(TASK): Given TASK, return the corresponding thread_info
107variable."""
108
109 def __init__(self):
110 super(LxThreadInfoFunc, self).__init__("lx_thread_info")
111
112 def invoke(self, task):
113 return get_thread_info(task)
114
115
116LxThreadInfoFunc()
117
118
119class LxThreadInfoByPidFunc (gdb.Function):
120 """Calculate Linux thread_info from task variable found by pid
121
122$lx_thread_info_by_pid(PID): Given PID, return the corresponding thread_info
123variable."""
124
125 def __init__(self):
126 super(LxThreadInfoByPidFunc, self).__init__("lx_thread_info_by_pid")
127
128 def invoke(self, pid):
129 task = get_task_by_pid(pid)
130 if task:
131 return get_thread_info(task.dereference())
132 else:
133 raise gdb.GdbError("No task of PID " + str(pid))
134
135
136LxThreadInfoByPidFunc()