Re: [PATCH] RFC: Add signal command to trace events

From: Oleg Nesterov
Date: Thu Jun 26 2014 - 12:47:00 EST


On 06/26, Oleg Nesterov wrote:
>
> > > +//ifdef CONFIG_TRACER_SIGNAL
> > > +static void
> > > +signal_trigger(struct event_trigger_data *data)
> > > +{
> > > + force_sig(SIGSTOP, current);
>
> Well, I don't like this. Imho, it would be nice to avoid signals here.
>
> And SIGSTOP in particular. It can interfere with the "real" SIGSTOP
> sent by user, with ptrace, with tty.

And I forgot to mention, note that SIGSTOP stops the whole thread group,
this is not what we want.

> I think we need something else... "STOP" is actually simple, but we need
> some interface which allows to wakeup a task sleeping in TASK_KILLABLE
> after it hits ETT_FREEZE.

Yes...

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/