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Date: Tue, 29 Jan 2002 18:16:37 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Andrew Morton <akpm@zip.com.au>
cc: Robert Love <rml@tech9.net>, <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:
>
> And llseek is *fast*.  If we're seeing significant
> lock contention in there then adding a schedule() is
> likely to turn Anton into one unhappy dbencher.

I'd agree, except I doubt there is every much contention on the _same_
file.

The reason llseek() ends up being so clear on the profiles is that it's a
very common system call under certain loads _and_ it uses a shared lock
for everything.

Also note the correctness issue (ie serialization on i_size), although
that is only an issue for SEEK_END (and maybe the lock should only be
gotten for that case. I'd love to hear what Al thinks..

		Linus

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