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 17 18 19task_type = utils.CachedType("struct task_struct") 20 21def task_lists(): 22 global task_type 23 task_ptr_type = task_type.get_type().pointer() 24 init_task = gdb.parse_and_eval("init_task").address 25 t = g = init_task 26 27 while True: 28 while True: 29 yield t 30 31 t = utils.container_of(t['thread_group']['next'], 32 task_ptr_type, "thread_group") 33 if t == g: 34 break 35 36 t = g = utils.container_of(g['tasks']['next'], 37 task_ptr_type, "tasks") 38 if t == init_task: 39 return 40 41def get_task_by_pid(pid): 42 for task in task_lists(): 43 if int(task['pid']) == pid: 44 return task 45 return None 46 47 48class LxTaskByPidFunc(gdb.Function): 49 """Find Linux task by PID and return the task_struct variable. 50 51$lx_task_by_pid(PID): Given PID, iterate over all tasks of the target and 52return that task_struct variable which PID matches.""" 53 54 def __init__(self): 55 super(LxTaskByPidFunc, self).__init__("lx_task_by_pid") 56 57 def invoke(self, pid): 58 task = get_task_by_pid(pid) 59 if task: 60 return task.dereference() 61 else: 62 raise gdb.GdbError("No task of PID " + str(pid)) 63 64 65LxTaskByPidFunc() 66 67 68thread_info_type = utils.CachedType("struct thread_info") 69 70ia64_task_size = None 71 72 73def get_thread_info(task): 74 global thread_info_type 75 thread_info_ptr_type = thread_info_type.get_type().pointer() 76 if utils.is_target_arch("ia64"): 77 global ia64_task_size 78 if ia64_task_size is None: 79 ia64_task_size = gdb.parse_and_eval("sizeof(struct task_struct)") 80 thread_info_addr = task.address + ia64_task_size 81 thread_info = thread_info_addr.cast(thread_info_ptr_type) 82 else: 83 thread_info = task['stack'].cast(thread_info_ptr_type) 84 return thread_info.dereference() 85 86 87class LxThreadInfoFunc (gdb.Function): 88 """Calculate Linux thread_info from task variable. 89 90$lx_thread_info(TASK): Given TASK, return the corresponding thread_info 91variable.""" 92 93 def __init__(self): 94 super(LxThreadInfoFunc, self).__init__("lx_thread_info") 95 96 def invoke(self, task): 97 return get_thread_info(task) 98 99 100LxThreadInfoFunc() 101