[PATCH] Show thread_info->flags in /proc/PID/status

[PATCH] Show thread_info->flags in /proc/PID/status

[Roland McGrath]

It comes up as useful in debugging to be able to see task->thread_info->flags
along with signal information and such.  There is no way currently to
elicit these bits from the kernel via sysrq or /proc (AFAIK).
This patch adds the field to /proc/PID/status.


Thanks,
Roland

Signed-off-by: Roland McGrath <roland@redhat.com>


--- linux-2.6/fs/proc/array.c
+++ linux-2.6/fs/proc/array.c
@@ -287,6 +287,12 @@ static inline char *task_cap(struct task
 			    cap_t(p->cap_effective));
 }
 
+static inline char *task_tif(struct task_struct *p, char *buffer)
+{
+	return buffer + sprintf(buffer, "ThreadInfoFlags:\t%lu\n",
+				(unsigned long) p->thread_info->flags);
+}
+
 int proc_pid_status(struct task_struct *task, char * buffer)
 {
 	char * orig = buffer;
@@ -294,6 +300,7 @@ int proc_pid_status(struct task_struct *
 
 	buffer = task_name(task, buffer);
 	buffer = task_state(task, buffer);
+	buffer = task_tif(task, buffer);
  
 	if (mm) {
 		buffer = task_mem(mm, buffer);

Re: [PATCH] Show thread_info->flags in /proc/PID/status

[Andrew Morton]

Roland McGrath <roland@redhat.com> wrote:
>
> It comes up as useful in debugging to be able to see task->thread_info->flags
> along with signal information and such.  There is no way currently to
> elicit these bits from the kernel via sysrq or /proc (AFAIK).
> This patch adds the field to /proc/PID/status.
> 
> ...
> 
> --- linux-2.6/fs/proc/array.c
> +++ linux-2.6/fs/proc/array.c
> @@ -287,6 +287,12 @@ static inline char *task_cap(struct task
>  			    cap_t(p->cap_effective));
>  }
>  
> +static inline char *task_tif(struct task_struct *p, char *buffer)
> +{
> +	return buffer + sprintf(buffer, "ThreadInfoFlags:\t%lu\n",
> +				(unsigned long) p->thread_info->flags);
> +}

Alas, thread_info.flags is an arch-specific thing and m68k doesn't
implement it.  All other architectures do, though.

Maybe we should show thread_info->flags in the sysrq-t output instead?