[media] staging: media: davinci_vpfe: unlock on error in vpfe_reqbufs()
[linux/fpc-iii.git] / Documentation / kdump / gdbmacros.txt
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2 # This file contains a few gdb macros (user defined commands) to extract
3 # useful information from kernel crashdump (kdump) like stack traces of
4 # all the processes or a particular process and trapinfo.
6 # These macros can be used by copying this file in .gdbinit (put in home
7 # directory or current directory) or by invoking gdb command with
8 # --command=<command-file-name> option
10 # Credits:
11 # Alexander Nyberg <alexn@telia.com>
12 # V Srivatsa <vatsa@in.ibm.com>
13 # Maneesh Soni <maneesh@in.ibm.com>
16 define bttnobp
17         set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
18         set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
19         set $init_t=&init_task
20         set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
21         set var $stacksize = sizeof(union thread_union)
22         while ($next_t != $init_t)
23                 set $next_t=(struct task_struct *)$next_t
24                 printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
25                 printf "===================\n"
26                 set var $stackp = $next_t.thread.sp
27                 set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
29                 while ($stackp < $stack_top)
30                         if (*($stackp) > _stext && *($stackp) < _sinittext)
31                                 info symbol *($stackp)
32                         end
33                         set $stackp += 4
34                 end
35                 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
36                 while ($next_th != $next_t)
37                         set $next_th=(struct task_struct *)$next_th
38                         printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
39                         printf "===================\n"
40                         set var $stackp = $next_t.thread.sp
41                         set var $stack_top = ($stackp & ~($stacksize - 1)) + stacksize
43                         while ($stackp < $stack_top)
44                                 if (*($stackp) > _stext && *($stackp) < _sinittext)
45                                         info symbol *($stackp)
46                                 end
47                                 set $stackp += 4
48                         end
49                         set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
50                 end
51                 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
52         end
53 end
54 document bttnobp
55         dump all thread stack traces on a kernel compiled with !CONFIG_FRAME_POINTER
56 end
58 define btthreadstack
59         set var $pid_task = $arg0
61         printf "\npid %d; comm %s:\n", $pid_task.pid, $pid_task.comm
62         printf "task struct: "
63         print $pid_task
64         printf "===================\n"
65         set var $stackp = $pid_task.thread.sp
66         set var $stacksize = sizeof(union thread_union)
67         set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
68         set var $stack_bot = ($stackp & ~($stacksize - 1))
70         set $stackp = *((unsigned long *) $stackp)
71         while (($stackp < $stack_top) && ($stackp > $stack_bot))
72                 set var $addr = *(((unsigned long *) $stackp) + 1)
73                 info symbol $addr
74                 set $stackp = *((unsigned long *) $stackp)
75         end
76 end
77 document btthreadstack
78          dump a thread stack using the given task structure pointer
79 end
82 define btt
83         set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
84         set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
85         set $init_t=&init_task
86         set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
87         while ($next_t != $init_t)
88                 set $next_t=(struct task_struct *)$next_t
89                 btthreadstack $next_t
91                 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
92                 while ($next_th != $next_t)
93                         set $next_th=(struct task_struct *)$next_th
94                         btthreadstack $next_th
95                         set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
96                 end
97                 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
98         end
99 end
100 document btt
101         dump all thread stack traces on a kernel compiled with CONFIG_FRAME_POINTER
104 define btpid
105         set var $pid = $arg0
106         set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
107         set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
108         set $init_t=&init_task
109         set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
110         set var $pid_task = 0
112         while ($next_t != $init_t)
113                 set $next_t=(struct task_struct *)$next_t
115                 if ($next_t.pid == $pid)
116                         set $pid_task = $next_t
117                 end
119                 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
120                 while ($next_th != $next_t)
121                         set $next_th=(struct task_struct *)$next_th
122                         if ($next_th.pid == $pid)
123                                 set $pid_task = $next_th
124                         end
125                         set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
126                 end
127                 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
128         end
130         btthreadstack $pid_task
132 document btpid
133         backtrace of pid
137 define trapinfo
138         set var $pid = $arg0
139         set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
140         set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
141         set $init_t=&init_task
142         set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
143         set var $pid_task = 0
145         while ($next_t != $init_t)
146                 set $next_t=(struct task_struct *)$next_t
148                 if ($next_t.pid == $pid)
149                         set $pid_task = $next_t
150                 end
152                 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
153                 while ($next_th != $next_t)
154                         set $next_th=(struct task_struct *)$next_th
155                         if ($next_th.pid == $pid)
156                                 set $pid_task = $next_th
157                         end
158                         set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
159                 end
160                 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
161         end
163         printf "Trapno %ld, cr2 0x%lx, error_code %ld\n", $pid_task.thread.trap_no, \
164                                 $pid_task.thread.cr2, $pid_task.thread.error_code
167 document trapinfo
168         Run info threads and lookup pid of thread #1
169         'trapinfo <pid>' will tell you by which trap & possibly
170         address the kernel panicked.
173 define dump_log_idx
174         set $idx = $arg0
175         if ($argc > 1)
176                 set $prev_flags = $arg1
177         else
178                 set $prev_flags = 0
179         end
180         set $msg = ((struct printk_log *) (log_buf + $idx))
181         set $prefix = 1
182         set $newline = 1
183         set $log = log_buf + $idx + sizeof(*$msg)
185         # prev & LOG_CONT && !(msg->flags & LOG_PREIX)
186         if (($prev_flags & 8) && !($msg->flags & 4))
187                 set $prefix = 0
188         end
190         # msg->flags & LOG_CONT
191         if ($msg->flags & 8)
192                 # (prev & LOG_CONT && !(prev & LOG_NEWLINE))
193                 if (($prev_flags & 8) && !($prev_flags & 2))
194                         set $prefix = 0
195                 end
196                 # (!(msg->flags & LOG_NEWLINE))
197                 if (!($msg->flags & 2))
198                         set $newline = 0
199                 end
200         end
202         if ($prefix)
203                 printf "[%5lu.%06lu] ", $msg->ts_nsec / 1000000000, $msg->ts_nsec % 1000000000
204         end
205         if ($msg->text_len != 0)
206                 eval "printf \"%%%d.%ds\", $log", $msg->text_len, $msg->text_len
207         end
208         if ($newline)
209                 printf "\n"
210         end
211         if ($msg->dict_len > 0)
212                 set $dict = $log + $msg->text_len
213                 set $idx = 0
214                 set $line = 1
215                 while ($idx < $msg->dict_len)
216                         if ($line)
217                                 printf " "
218                                 set $line = 0
219                         end
220                         set $c = $dict[$idx]
221                         if ($c == '\0')
222                                 printf "\n"
223                                 set $line = 1
224                         else
225                                 if ($c < ' ' || $c >= 127 || $c == '\\')
226                                         printf "\\x%02x", $c
227                                 else
228                                         printf "%c", $c
229                                 end
230                         end
231                         set $idx = $idx + 1
232                 end
233                 printf "\n"
234         end
236 document dump_log_idx
237         Dump a single log given its index in the log buffer.  The first
238         parameter is the index into log_buf, the second is optional and
239         specified the previous log buffer's flags, used for properly
240         formatting continued lines.
243 define dmesg
244         set $i = log_first_idx
245         set $end_idx = log_first_idx
246         set $prev_flags = 0
248         while (1)
249                 set $msg = ((struct printk_log *) (log_buf + $i))
250                 if ($msg->len == 0)
251                         set $i = 0
252                 else
253                         dump_log_idx $i $prev_flags
254                         set $i = $i + $msg->len
255                         set $prev_flags = $msg->flags
256                 end
257                 if ($i == $end_idx)
258                         loop_break
259                 end
260         end
262 document dmesg
263         print the kernel ring buffer