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To: arch@freebsd.org
From: Poul-Henning Kamp <phk@phk.freebsd.dk>
Date: Sun, 05 Mar 2006 11:18:08 +0000
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Cc: 
Subject: wakeup idea...
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Here is a possibly stupid idea.

Historically sleep/wakeup have happened on a pointer which was just
a magic number.

In many cases, this pointer is actually a relevant datastructure.

Would it possibly be an optimization to make a variant of the
sleep/wakeup calls where the pointer points to an integer type which
contains non-zero if anybody is actually sleeping on that address ?

Anybody up for a quick prototype ?

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.