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$lx_task_by_pid(PID): Given PID, iterate over all tasks of the target and 49return that task_struct variable which PID matches.""" 50 51 def __init__(self): 52 super(LxTaskByPidFunc, self).__init__("lx_task_by_pid") 53 54 def invoke(self, pid): 55 task = get_task_by_pid(pid) 56 if task: 57 return task.dereference() 58 else: 59 raise gdb.GdbError("No task of PID " + str(pid)) 60 61 62LxTaskByPidFunc() 63 64 65class LxPs(gdb.Command): 66 """Dump Linux tasks.""" 67 68 def __init__(self): 69 super(LxPs, self).__init__("lx-ps", gdb.COMMAND_DATA) 70 71 def invoke(self, arg, from_tty): 72 gdb.write("{:>10} {:>12} {:>7}\n".format("TASK", "PID", "COMM")) 73 for task in task_lists(): 74 gdb.write("{} {:^5} {}\n".format( 75 task.format_string().split()[0], 76 task["pid"].format_string(), 77 task["comm"].string())) 78 79 80LxPs() 81 82 83thread_info_type = utils.CachedType("struct thread_info") 84 85 86def get_thread_info(task): 87 thread_info_ptr_type = thread_info_type.get_type().pointer() 88 if task_type.get_type().fields()[0].type == thread_info_type.get_type(): 89 return task['thread_info'] 90 thread_info = task['stack'].cast(thread_info_ptr_type) 91 return thread_info.dereference() 92 93 94class LxThreadInfoFunc (gdb.Function): 95 """Calculate Linux thread_info from task variable. 96 97$lx_thread_info(TASK): Given TASK, return the corresponding thread_info 98variable.""" 99 100 def __init__(self): 101 super(LxThreadInfoFunc, self).__init__("lx_thread_info") 102 103 def invoke(self, task): 104 return get_thread_info(task) 105 106 107LxThreadInfoFunc() 108 109 110class LxThreadInfoByPidFunc (gdb.Function): 111 """Calculate Linux thread_info from task variable found by pid 112 113$lx_thread_info_by_pid(PID): Given PID, return the corresponding thread_info 114variable.""" 115 116 def __init__(self): 117 super(LxThreadInfoByPidFunc, self).__init__("lx_thread_info_by_pid") 118 119 def invoke(self, pid): 120 task = get_task_by_pid(pid) 121 if task: 122 return get_thread_info(task.dereference()) 123 else: 124 raise gdb.GdbError("No task of PID " + str(pid)) 125 126 127LxThreadInfoByPidFunc() 128