Cc Andrew and Jonathan.

On 05/10/16 at 07:30pm, miny...@acm.org wrote:
> From: Corey Minyard <cminy...@mvista.com>
> 
> Lots of little changes needed to be made to clean these up, remove the
> four byte pointer assumption and traverse the pid queue properly.
> Also consolidate the traceback code into a single function instead
> of having three copies of it.
> 
> Signed-off-by: Corey Minyard <cminy...@mvista.com>
> ---
> 
> Changes since v1:
> 
> Rename btthreadstruct to btthreadstack
> 
> Use sizeof(union thread_union) for the stack size instead of a hardcoded
> 4096.
> 
>  Documentation/kdump/gdbmacros.txt | 96 
> ++++++++++++++++++---------------------
>  1 file changed, 44 insertions(+), 52 deletions(-)
> 
> diff --git a/Documentation/kdump/gdbmacros.txt 
> b/Documentation/kdump/gdbmacros.txt
> index 9b9b454..35f6a98 100644
> --- a/Documentation/kdump/gdbmacros.txt
> +++ b/Documentation/kdump/gdbmacros.txt
> @@ -15,15 +15,16 @@
>  
>  define bttnobp
>       set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
> -     set $pid_off=((size_t)&((struct task_struct *)0)->pids[1].pid_list.next)
> +     set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
>       set $init_t=&init_task
>       set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
> +     set var $stacksize = sizeof(union thread_union)
>       while ($next_t != $init_t)
>               set $next_t=(struct task_struct *)$next_t
>               printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
>               printf "===================\n"
> -             set var $stackp = $next_t.thread.esp
> -             set var $stack_top = ($stackp & ~4095) + 4096
> +             set var $stackp = $next_t.thread.sp
> +             set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
>  
>               while ($stackp < $stack_top)
>                       if (*($stackp) > _stext && *($stackp) < _sinittext)
> @@ -31,13 +32,13 @@ define bttnobp
>                       end
>                       set $stackp += 4
>               end
> -             set $next_th=(((char *)$next_t->pids[1].pid_list.next) - 
> $pid_off)
> +             set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
>               while ($next_th != $next_t)
>                       set $next_th=(struct task_struct *)$next_th
>                       printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
>                       printf "===================\n"
> -                     set var $stackp = $next_t.thread.esp
> -                     set var $stack_top = ($stackp & ~4095) + 4096
> +                     set var $stackp = $next_t.thread.sp
> +                     set var $stack_top = ($stackp & ~($stacksize - 1)) + 
> stacksize
>  
>                       while ($stackp < $stack_top)
>                               if (*($stackp) > _stext && *($stackp) < 
> _sinittext)
> @@ -45,7 +46,7 @@ define bttnobp
>                               end
>                               set $stackp += 4
>                       end
> -                     set $next_th=(((char *)$next_th->pids[1].pid_list.next) 
> - $pid_off)
> +                     set $next_th=(((char *)$next_th->thread_group.next) - 
> $pid_off)
>               end
>               set $next_t=(char *)($next_t->tasks.next) - $tasks_off
>       end
> @@ -54,42 +55,44 @@ document bttnobp
>       dump all thread stack traces on a kernel compiled with 
> !CONFIG_FRAME_POINTER
>  end
>  
> +define btthreadstack
> +     set var $pid_task = $arg0
> +
> +     printf "\npid %d; comm %s:\n", $pid_task.pid, $pid_task.comm
> +     printf "task struct: "
> +     print $pid_task
> +     printf "===================\n"
> +     set var $stackp = $pid_task.thread.sp
> +     set var $stacksize = sizeof(union thread_union)
> +     set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
> +     set var $stack_bot = ($stackp & ~($stacksize - 1))
> +
> +     set $stackp = *((unsigned long *) $stackp)
> +     while (($stackp < $stack_top) && ($stackp > $stack_bot))
> +             set var $addr = *(((unsigned long *) $stackp) + 1)
> +             info symbol $addr
> +             set $stackp = *((unsigned long *) $stackp)
> +     end
> +end
> +document btthreadstack
> +      dump a thread stack using the given task structure pointer
> +end
> +
> +
>  define btt
>       set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
> -     set $pid_off=((size_t)&((struct task_struct *)0)->pids[1].pid_list.next)
> +     set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
>       set $init_t=&init_task
>       set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
>       while ($next_t != $init_t)
>               set $next_t=(struct task_struct *)$next_t
> -             printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
> -             printf "===================\n"
> -             set var $stackp = $next_t.thread.esp
> -             set var $stack_top = ($stackp & ~4095) + 4096
> -             set var $stack_bot = ($stackp & ~4095)
> -
> -             set $stackp = *($stackp)
> -             while (($stackp < $stack_top) && ($stackp > $stack_bot))
> -                     set var $addr = *($stackp + 4)
> -                     info symbol $addr
> -                     set $stackp = *($stackp)
> -             end
> +             btthreadstack $next_t
>  
> -             set $next_th=(((char *)$next_t->pids[1].pid_list.next) - 
> $pid_off)
> +             set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
>               while ($next_th != $next_t)
>                       set $next_th=(struct task_struct *)$next_th
> -                     printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
> -                     printf "===================\n"
> -                     set var $stackp = $next_t.thread.esp
> -                     set var $stack_top = ($stackp & ~4095) + 4096
> -                     set var $stack_bot = ($stackp & ~4095)
> -
> -                     set $stackp = *($stackp)
> -                     while (($stackp < $stack_top) && ($stackp > $stack_bot))
> -                             set var $addr = *($stackp + 4)
> -                             info symbol $addr
> -                             set $stackp = *($stackp)
> -                     end
> -                     set $next_th=(((char *)$next_th->pids[1].pid_list.next) 
> - $pid_off)
> +                     btthreadstack $next_th
> +                     set $next_th=(((char *)$next_th->thread_group.next) - 
> $pid_off)
>               end
>               set $next_t=(char *)($next_t->tasks.next) - $tasks_off
>       end
> @@ -101,7 +104,7 @@ end
>  define btpid
>       set var $pid = $arg0
>       set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
> -     set $pid_off=((size_t)&((struct task_struct *)0)->pids[1].pid_list.next)
> +     set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
>       set $init_t=&init_task
>       set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
>       set var $pid_task = 0
> @@ -113,29 +116,18 @@ define btpid
>                       set $pid_task = $next_t
>               end
>  
> -             set $next_th=(((char *)$next_t->pids[1].pid_list.next) - 
> $pid_off)
> +             set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
>               while ($next_th != $next_t)
>                       set $next_th=(struct task_struct *)$next_th
>                       if ($next_th.pid == $pid)
>                               set $pid_task = $next_th
>                       end
> -                     set $next_th=(((char *)$next_th->pids[1].pid_list.next) 
> - $pid_off)
> +                     set $next_th=(((char *)$next_th->thread_group.next) - 
> $pid_off)
>               end
>               set $next_t=(char *)($next_t->tasks.next) - $tasks_off
>       end
>  
> -     printf "\npid %d; comm %s:\n", $pid_task.pid, $pid_task.comm
> -     printf "===================\n"
> -     set var $stackp = $pid_task.thread.esp
> -     set var $stack_top = ($stackp & ~4095) + 4096
> -     set var $stack_bot = ($stackp & ~4095)
> -
> -     set $stackp = *($stackp)
> -     while (($stackp < $stack_top) && ($stackp > $stack_bot))
> -             set var $addr = *($stackp + 4)
> -             info symbol $addr
> -             set $stackp = *($stackp)
> -     end
> +     btthreadstack $pid_task
>  end
>  document btpid
>       backtrace of pid
> @@ -145,7 +137,7 @@ end
>  define trapinfo
>       set var $pid = $arg0
>       set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
> -     set $pid_off=((size_t)&((struct task_struct *)0)->pids[1].pid_list.next)
> +     set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
>       set $init_t=&init_task
>       set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
>       set var $pid_task = 0
> @@ -157,13 +149,13 @@ define trapinfo
>                       set $pid_task = $next_t
>               end
>  
> -             set $next_th=(((char *)$next_t->pids[1].pid_list.next) - 
> $pid_off)
> +             set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
>               while ($next_th != $next_t)
>                       set $next_th=(struct task_struct *)$next_th
>                       if ($next_th.pid == $pid)
>                               set $pid_task = $next_th
>                       end
> -                     set $next_th=(((char *)$next_th->pids[1].pid_list.next) 
> - $pid_off)
> +                     set $next_th=(((char *)$next_th->thread_group.next) - 
> $pid_off)
>               end
>               set $next_t=(char *)($next_t->tasks.next) - $tasks_off
>       end
> -- 
> 2.7.4
> 
> 
> _______________________________________________
> kexec mailing list
> ke...@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec

Reply via email to