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Date: Wed, 30 Jan 2002 01:34:28 -0800 (PST)
From: Nigel Gamble <nigel@nrg.org>
Reply-To: nigel@nrg.org
To: Andrew Morton <akpm@zip.com.au>
cc: Robert Love <rml@tech9.net>, Linus Torvalds <torvalds@transmeta.com>,
        <viro@math.psu.edu>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] 2.5: push BKL out of llseek
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On Tue, 29 Jan 2002, Andrew Morton wrote:
> Nigel Gamble wrote:
> > Am I remembering the problem correctly?
>
> I don't think so :)
>
> The problem was that the semaphore was highly contended, so the
> losing process was explicitly scheduling away.
>
> This doesn't necessarily mean that it was a long-held lock.  In
> this case, it was a short-held lock, but it was also very *frequently*
> being held and released.   This is a scenario where a spinlock is
> heaps more appropriate than a semaphore.

Oh, well in that case, I agree that a spinlock is more appropriate.

Nigel Gamble                                    nigel@nrg.org
Mountain View, CA, USA.                         http://www.nrg.org/

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