Re: [PATCH] proc: remove /proc/*/status "Stack usage:"

From: Stefani Seibold
Date: Sun Nov 01 2009 - 18:32:33 EST


Am Sonntag, den 01.11.2009, 18:53 +0300 schrieb Alexey Dobriyan:
> On Sun, Nov 01, 2009 at 03:39:57PM +0100, Stefani Seibold wrote:
> > Am Sonntag, den 01.11.2009, 16:15 +0300 schrieb Alexey Dobriyan:
> > > We have /proc/*/pagemap to determine how much stack was consumed.
> > > Leave "threadstack" though.
> > >
> >
> > Stop! /proc/*/pagemap is not a real substitute for the stackm usage
> > patch. If you have problems with this patch i will have a look on it.
>
> Why?
>
> You grab thread stack start from /proc/*/stat, then for every page of
> stack VMA, you lookup state of page, which is exactly what you're doing
> by employing page walker.

First, as you figured out there is currently no way to get the stack
start of a thread. But i currently check this and hope to find a
solution in the next 24 hours.

Second, this patch aims to the embedded world and there is normally no
tools available when you need it, but /proc is always there. Especially
outside in the field.

Like Dr Frank. N. Furter in the "Rocky Horror Picture Show" says: remove
the cause but NOT the symptoms!

And the cause is the miss implemented KSTK_ESP in a x86_64. I also
checked all other architekture depended KSTK_ESP definitions and this
definitions looks okay for me.

Stand by....


--
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/