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Date: Fri, 8 Feb 2002 22:23:27 +0100 (CET)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: <mingo@elte.hu>
To: Alexander Viro <viro@math.psu.edu>
Cc: Linus Torvalds <torvalds@transmeta.com>, Andrew Morton <akpm@zip.com.au>,
        Martin Wirth <Martin.Wirth@dlr.de>, Robert Love <rml@tech9.net>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        haveblue <haveblue@us.ibm.com>
Subject: Re: [RFC] New locking primitive for 2.5
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On Fri, 8 Feb 2002, Alexander Viro wrote:

> Had anyone actually seen lseek() vs. lseek() contention prior to the
> switch to ->i_sem-based variant? [...]

yes, i've seen this for years. (if you accept dbench overhead.)

and regarding the reintroduction of BKL, *please* do not just use a global
locks around such pieces of code, lock bouncing sucks on SMP, even if
there is no overhead.

	Ingo

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