Re: [RFC 5/5] uprobes: add global breakpoints

[Oleg Nesterov]

On 08/09, Sebastian Andrzej Siewior wrote:
>
> * Oleg Nesterov | 2012-08-08 15:14:57 [+0200]:
>
> >> What I miss right now is an interface to tell the user/gdb that there is a
> >> program that hit a global breakpoint and is waiting for further instructions.
> >> A "tail -f trace" does not work and may contain also a lot of other
> >> informations. I've been thinking about a poll()able file which returns pids of
> >> tasks which are put on hold. Other suggestions?
> >
> >Honestly, I am not sure this is that useful...
>
> How would you notify gdb that there is a new task that hit a breakpoint?
> Or learn yourself?

But why do we need this?

OK, you do not need to convince me, I try to never argue with
new features.

However, I certainly dislike TASK_TRACED in uprobe_wait_traced().
And sleeping in ->handler() is not fair to other consumers.

And I do not think you should modify ptrace_attach() at all.
gdb/user can wakeup the task after PTRACE_ATTACH itself.

Oleg.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/