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Date: Thu, 28 Feb 2002 21:00:26 -0500
From: Hubertus Franke <frankeh@watson.ibm.com>
To: Rusty Russell <rusty@rustcorp.com.au>, torvalds@transmeta.com,
        matthew@hairy.beasts.org, bcrl@redhat.com, david@mysql.com,
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Subject: Re: [PATCH] Lightweight userspace semaphores...
Message-ID: <20020228210026.A3070@elinux01.watson.ibm.com>
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In-Reply-To: <20020228162422.A947@twiddle.net>; from rth@twiddle.net on Thu, Feb 28, 2002 at 04:24:22PM -0800
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On Thu, Feb 28, 2002 at 04:24:22PM -0800, Richard Henderson wrote:
> On Wed, Feb 27, 2002 at 10:53:11AM -0500, Hubertus Franke wrote:
> > As stated above, I allocate a kernel object <kulock_t> on demand and
> > hash it. This way I don't have to pin any user address. What does everybody
> > think about the merit of this approach versus the pinning approach?
> [...]
> > In your case, can the lock be allocated at different
> > virtual addresses in the various address spaces.
> 
> I think this is a relatively important feature.  It may not be
> possible to use the same virtual address in different processes.
> 
> 
> r~

I think so too. However let me point that Linus's initial recommendation
of a handle, comprised of a kernel pointer and a signature also has
that property.
Just pointing out the merits of the various approaches.

-- Hubertus

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