Re: [PATCH] Introduce ActivePid: in /proc/self/status (v2, wasVpid:)

From: Greg Kurz
Date: Thu Jun 16 2011 - 11:02:02 EST

On Thu, 2011-06-16 at 15:25 +0200, Louis Rilling wrote:
> > Ok. You're right, the RCU grace period is just what I need to ensure
> I
> > won't dereference a stale pointer. So I don't even have to bother
> with
> > ->siglock and just check pid_alive() before peeking into
> pid->numbers.
> It ends like open-coding an optimized version of task_pid_vnr(). If
> the
> optimization is really important (I guess this depends on the depth of
> recursive
> pid namespaces), it would be better to re-write task_pid_vnr().
> Otherwise, just
> use task_pid_vnr() as it is.
> Thanks,
> Louis
Hmm, sorry Louis but I'm looking for the pid number from the task active
pid_ns (AKA. the return value of getpid() if called by this task), so
task_pid_vnr() doesn't fit.

About the open-coding argument, that's why I used task_pid_nr_ns() and
task_active_pid_ns() at first...

Gregory Kurz gkurz@xxxxxxxxxx
Software Engineer @ IBM/Meiosys
Tel +33 (0)534 638 479 Fax +33 (0)561 400 420

"Anarchy is about taking complete responsibility for yourself."
Alan Moore.

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